package antlr;
/* ANTLR Translator Generator
* Project led by Terence Parr at http://www.jGuru.com
* Software rights: http://www.antlr.org/RIGHTS.html
*
* $Id: JavaCodeGenerator.java,v 1.1 2004/01/21 19:18:31 rgrimm Exp $
*/
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.HashSet;
import antlr.collections.impl.BitSet;
import antlr.collections.impl.Vector;
import java.io.PrintWriter; //SAS: changed for proper text file io
import java.io.IOException;
import java.io.FileWriter;
/**Generate MyParser.java, MyLexer.java and MyParserTokenTypes.java */
public class JavaCodeGenerator extends CodeGenerator {
// non-zero if inside syntactic predicate generation
protected int syntacticPredLevel = 0;
// Are we generating ASTs (for parsers and tree parsers) right now?
protected boolean genAST = false;
// Are we saving the text consumed (for lexers) right now?
protected boolean saveText = false;
// Grammar parameters set up to handle different grammar classes.
// These are used to get instanceof tests out of code generation
String labeledElementType;
String labeledElementASTType;
String labeledElementInit;
String commonExtraArgs;
String commonExtraParams;
String commonLocalVars;
String lt1Value;
String exceptionThrown;
String throwNoViable;
/** Tracks the rule being generated. Used for mapTreeId */
RuleBlock currentRule;
/** Tracks the rule or labeled subrule being generated. Used for
AST generation. */
String currentASTResult;
/** Mapping between the ids used in the current alt, and the
* names of variables used to represent their AST values.
*/
Hashtable treeVariableMap = new Hashtable();
/** Used to keep track of which AST variables have been defined in a rule
* (except for the #rule_name and #rule_name_in var's
*/
HashSet declaredASTVariables = new HashSet();
/* Count of unnamed generated variables */
int astVarNumber = 1;
/** Special value used to mark duplicate in treeVariableMap */
protected static final String NONUNIQUE = new String();
public static final int caseSizeThreshold = 127; // ascii is max
private Vector semPreds;
/** Create a Java code-generator using the given Grammar.
* The caller must still call setTool, setBehavior, and setAnalyzer
* before generating code.
*/
public JavaCodeGenerator() {
super();
charFormatter = new JavaCharFormatter();
}
/** Adds a semantic predicate string to the sem pred vector
These strings will be used to build an array of sem pred names
when building a debugging parser. This method should only be
called when the debug option is specified
*/
protected int addSemPred(String predicate) {
semPreds.appendElement(predicate);
return semPreds.size() - 1;
}
public void exitIfError() {
if (antlrTool.hasError()) {
antlrTool.fatalError("Exiting due to errors.");
}
}
/**Generate the parser, lexer, treeparser, and token types in Java */
public void gen() {
// Do the code generation
try {
// Loop over all grammars
Enumeration grammarIter = behavior.grammars.elements();
while (grammarIter.hasMoreElements()) {
Grammar g = (Grammar)grammarIter.nextElement();
// Connect all the components to each other
g.setGrammarAnalyzer(analyzer);
g.setCodeGenerator(this);
analyzer.setGrammar(g);
// To get right overloading behavior across hetrogeneous grammars
setupGrammarParameters(g);
g.generate();
// print out the grammar with lookahead sets (and FOLLOWs)
// System.out.print(g.toString());
exitIfError();
}
// Loop over all token managers (some of which are lexers)
Enumeration tmIter = behavior.tokenManagers.elements();
while (tmIter.hasMoreElements()) {
TokenManager tm = (TokenManager)tmIter.nextElement();
if (!tm.isReadOnly()) {
// Write the token manager tokens as Java
// this must appear before genTokenInterchange so that
// labels are set on string literals
genTokenTypes(tm);
// Write the token manager tokens as plain text
genTokenInterchange(tm);
}
exitIfError();
}
}
catch (IOException e) {
antlrTool.reportException(e, null);
}
}
/** Generate code for the given grammar element.
* @param blk The {...} action to generate
*/
public void gen(ActionElement action) {
if (DEBUG_CODE_GENERATOR) System.out.println("genAction(" + action + ")");
if (action.isSemPred) {
genSemPred(action.actionText, action.line);
}
else {
if (grammar.hasSyntacticPredicate) {
println("if ( inputState.guessing==0 ) {");
tabs++;
}
// get the name of the followSet for the current rule so that we
// can replace $FOLLOW in the .g file.
ActionTransInfo tInfo = new ActionTransInfo();
String actionStr = processActionForSpecialSymbols(action.actionText,
action.getLine(),
currentRule,
tInfo);
if (tInfo.refRuleRoot != null) {
// Somebody referenced "#rule", make sure translated var is valid
// assignment to #rule is left as a ref also, meaning that assignments
// with no other refs like "#rule = foo();" still forces this code to be
// generated (unnecessarily).
println(tInfo.refRuleRoot + " = (" + labeledElementASTType + ")currentAST.root;");
}
// dump the translated action
printAction(actionStr);
if (tInfo.assignToRoot) {
// Somebody did a "#rule=", reset internal currentAST.root
println("currentAST.root = " + tInfo.refRuleRoot + ";");
// reset the child pointer too to be last sibling in sibling list
println("currentAST.child = " + tInfo.refRuleRoot + "!=null &&" + tInfo.refRuleRoot + ".getFirstChild()!=null ?");
tabs++;
println(tInfo.refRuleRoot + ".getFirstChild() : " + tInfo.refRuleRoot + ";");
tabs--;
println("currentAST.advanceChildToEnd();");
}
if (grammar.hasSyntacticPredicate) {
tabs--;
println("}");
}
}
}
/** Generate code for the given grammar element.
* @param blk The "x|y|z|..." block to generate
*/
public void gen(AlternativeBlock blk) {
if (DEBUG_CODE_GENERATOR) System.out.println("gen(" + blk + ")");
println("{");
genBlockPreamble(blk);
genBlockInitAction(blk);
// Tell AST generation to build subrule result
String saveCurrentASTResult = currentASTResult;
if (blk.getLabel() != null) {
currentASTResult = blk.getLabel();
}
boolean ok = grammar.theLLkAnalyzer.deterministic(blk);
JavaBlockFinishingInfo howToFinish = genCommonBlock(blk, true);
genBlockFinish(howToFinish, throwNoViable);
println("}");
// Restore previous AST generation
currentASTResult = saveCurrentASTResult;
}
/** Generate code for the given grammar element.
* @param blk The block-end element to generate. Block-end
* elements are synthesized by the grammar parser to represent
* the end of a block.
*/
public void gen(BlockEndElement end) {
if (DEBUG_CODE_GENERATOR) System.out.println("genRuleEnd(" + end + ")");
}
/** Generate code for the given grammar element.
* @param blk The character literal reference to generate
*/
public void gen(CharLiteralElement atom) {
if (DEBUG_CODE_GENERATOR) System.out.println("genChar(" + atom + ")");
if (atom.getLabel() != null) {
println(atom.getLabel() + " = " + lt1Value + ";");
}
boolean oldsaveText = saveText;
saveText = saveText && atom.getAutoGenType() == GrammarElement.AUTO_GEN_NONE;
genMatch(atom);
saveText = oldsaveText;
}
/** Generate code for the given grammar element.
* @param blk The character-range reference to generate
*/
public void gen(CharRangeElement r) {
if (r.getLabel() != null && syntacticPredLevel == 0) {
println(r.getLabel() + " = " + lt1Value + ";");
}
boolean flag = ( grammar instanceof LexerGrammar &&
( !saveText ||
r.getAutoGenType() ==
GrammarElement.AUTO_GEN_BANG ) );
if (flag) {
println("_saveIndex=text.length();");
}
println("matchRange(" + r.beginText + "," + r.endText + ");");
if (flag) {
println("text.setLength(_saveIndex);");
}
}
/** Generate the lexer Java file */
public void gen(LexerGrammar g) throws IOException {
// If debugging, create a new sempred vector for this grammar
if (g.debuggingOutput)
semPreds = new Vector();
setGrammar(g);
if (!(grammar instanceof LexerGrammar)) {
antlrTool.panic("Internal error generating lexer");
}
// SAS: moved output creation to method so a subclass can change
// how the output is generated (for VAJ interface)
setupOutput(grammar.getClassName());
genAST = false; // no way to gen trees.
saveText = true; // save consumed characters.
tabs = 0;
// Generate header common to all Java output files
genHeader();
// Do not use printAction because we assume tabs==0
println(behavior.getHeaderAction(""));
// Generate header specific to lexer Java file
// println("import java.io.FileInputStream;");
println("import java.io.InputStream;");
println("import antlr.TokenStreamException;");
println("import antlr.TokenStreamIOException;");
println("import antlr.TokenStreamRecognitionException;");
println("import antlr.CharStreamException;");
println("import antlr.CharStreamIOException;");
println("import antlr.ANTLRException;");
println("import java.io.Reader;");
println("import java.util.Hashtable;");
println("import antlr." + grammar.getSuperClass() + ";");
println("import antlr.InputBuffer;");
println("import antlr.ByteBuffer;");
println("import antlr.CharBuffer;");
println("import antlr.Token;");
println("import antlr.CommonToken;");
println("import antlr.RecognitionException;");
println("import antlr.NoViableAltForCharException;");
println("import antlr.MismatchedCharException;");
println("import antlr.TokenStream;");
println("import antlr.ANTLRHashString;");
println("import antlr.LexerSharedInputState;");
println("import antlr.collections.impl.BitSet;");
println("import antlr.SemanticException;");
// Generate user-defined lexer file preamble
println(grammar.preambleAction.getText());
// Generate lexer class definition
String sup = null;
if (grammar.superClass != null) {
sup = grammar.superClass;
}
else {
sup = "antlr." + grammar.getSuperClass();
}
// print javadoc comment if any
if (grammar.comment != null) {
_println(grammar.comment);
}
// get prefix (replaces "public" and lets user specify)
String prefix = "public";
Token tprefix = (Token)grammar.options.get("classHeaderPrefix");
if (tprefix != null) {
String p = StringUtils.stripFrontBack(tprefix.getText(), "\"", "\"");
if (p != null) {
prefix = p;
}
}
print(prefix+" ");
print("class " + grammar.getClassName() + " extends " + sup);
println(" implements " + grammar.tokenManager.getName() + TokenTypesFileSuffix + ", TokenStream");
Token tsuffix = (Token)grammar.options.get("classHeaderSuffix");
if (tsuffix != null) {
String suffix = StringUtils.stripFrontBack(tsuffix.getText(), "\"", "\"");
if (suffix != null) {
print(", " + suffix); // must be an interface name for Java
}
}
println(" {");
// Generate user-defined lexer class members
print(
processActionForSpecialSymbols(grammar.classMemberAction.getText(), grammar.classMemberAction.getLine(), currentRule, null)
);
//
// Generate the constructor from InputStream, which in turn
// calls the ByteBuffer constructor
//
println("public " + grammar.getClassName() + "(InputStream in) {");
tabs++;
println("this(new ByteBuffer(in));");
tabs--;
println("}");
//
// Generate the constructor from Reader, which in turn
// calls the CharBuffer constructor
//
println("public " + grammar.getClassName() + "(Reader in) {");
tabs++;
println("this(new CharBuffer(in));");
tabs--;
println("}");
println("public " + grammar.getClassName() + "(InputBuffer ib) {");
tabs++;
// if debugging, wrap the input buffer in a debugger
if (grammar.debuggingOutput)
println("this(new LexerSharedInputState(new antlr.debug.DebuggingInputBuffer(ib)));");
else
println("this(new LexerSharedInputState(ib));");
tabs--;
println("}");
//
// Generate the constructor from InputBuffer (char or byte)
//
println("public " + grammar.getClassName() + "(LexerSharedInputState state) {");
tabs++;
println("super(state);");
// if debugging, set up array variables and call user-overridable
// debugging setup method
if (grammar.debuggingOutput) {
println(" ruleNames = _ruleNames;");
println(" semPredNames = _semPredNames;");
println(" setupDebugging();");
}
// Generate the setting of various generated options.
// These need to be before the literals since ANTLRHashString depends on
// the casesensitive stuff.
println("caseSensitiveLiterals = " + g.caseSensitiveLiterals + ";");
println("setCaseSensitive(" + g.caseSensitive + ");");
// Generate the initialization of a hashtable
// containing the string literals used in the lexer
// The literals variable itself is in CharScanner
println("literals = new Hashtable();");
Enumeration keys = grammar.tokenManager.getTokenSymbolKeys();
while (keys.hasMoreElements()) {
String key = (String)keys.nextElement();
if (key.charAt(0) != '"') {
continue;
}
TokenSymbol sym = grammar.tokenManager.getTokenSymbol(key);
if (sym instanceof StringLiteralSymbol) {
StringLiteralSymbol s = (StringLiteralSymbol)sym;
println("literals.put(new ANTLRHashString(" + s.getId() + ", this), new Integer(" + s.getTokenType() + "));");
}
}
tabs--;
Enumeration ids;
println("}");
// generate the rule name array for debugging
if (grammar.debuggingOutput) {
println("private static final String _ruleNames[] = {");
ids = grammar.rules.elements();
int ruleNum = 0;
while (ids.hasMoreElements()) {
GrammarSymbol sym = (GrammarSymbol)ids.nextElement();
if (sym instanceof RuleSymbol)
println(" \"" + ((RuleSymbol)sym).getId() + "\",");
}
println("};");
}
// Generate nextToken() rule.
// nextToken() is a synthetic lexer rule that is the implicit OR of all
// user-defined lexer rules.
genNextToken();
// Generate code for each rule in the lexer
ids = grammar.rules.elements();
int ruleNum = 0;
while (ids.hasMoreElements()) {
RuleSymbol sym = (RuleSymbol)ids.nextElement();
// Don't generate the synthetic rules
if (!sym.getId().equals("mnextToken")) {
genRule(sym, false, ruleNum++);
}
exitIfError();
}
// Generate the semantic predicate map for debugging
if (grammar.debuggingOutput)
genSemPredMap();
// Generate the bitsets used throughout the lexer
genBitsets(bitsetsUsed, ((LexerGrammar)grammar).charVocabulary.size());
println("");
println("}");
// Close the lexer output stream
currentOutput.close();
currentOutput = null;
}
/** Generate code for the given grammar element.
* @param blk The (...)+ block to generate
*/
public void gen(OneOrMoreBlock blk) {
if (DEBUG_CODE_GENERATOR) System.out.println("gen+(" + blk + ")");
String label;
String cnt;
println("{");
genBlockPreamble(blk);
if (blk.getLabel() != null) {
cnt = "_cnt_" + blk.getLabel();
}
else {
cnt = "_cnt" + blk.ID;
}
println("int " + cnt + "=0;");
if (blk.getLabel() != null) {
label = blk.getLabel();
}
else {
label = "_loop" + blk.ID;
}
println(label + ":");
println("do {");
tabs++;
// generate the init action for ()+ ()* inside the loop
// this allows us to do usefull EOF checking...
genBlockInitAction(blk);
// Tell AST generation to build subrule result
String saveCurrentASTResult = currentASTResult;
if (blk.getLabel() != null) {
currentASTResult = blk.getLabel();
}
boolean ok = grammar.theLLkAnalyzer.deterministic(blk);
// generate exit test if greedy set to false
// and an alt is ambiguous with exit branch
// or when lookahead derived purely from end-of-file
// Lookahead analysis stops when end-of-file is hit,
// returning set {epsilon}. Since {epsilon} is not
// ambig with any real tokens, no error is reported
// by deterministic() routines and we have to check
// for the case where the lookahead depth didn't get
// set to NONDETERMINISTIC (this only happens when the
// FOLLOW contains real atoms + epsilon).
boolean generateNonGreedyExitPath = false;
int nonGreedyExitDepth = grammar.maxk;
if (!blk.greedy &&
blk.exitLookaheadDepth <= grammar.maxk &&
blk.exitCache[blk.exitLookaheadDepth].containsEpsilon()) {
generateNonGreedyExitPath = true;
nonGreedyExitDepth = blk.exitLookaheadDepth;
}
else if (!blk.greedy &&
blk.exitLookaheadDepth == LLkGrammarAnalyzer.NONDETERMINISTIC) {
generateNonGreedyExitPath = true;
}
// generate exit test if greedy set to false
// and an alt is ambiguous with exit branch
if (generateNonGreedyExitPath) {
if (DEBUG_CODE_GENERATOR) {
System.out.println("nongreedy (...)+ loop; exit depth is " +
blk.exitLookaheadDepth);
}
String predictExit =
getLookaheadTestExpression(blk.exitCache,
nonGreedyExitDepth);
println("// nongreedy exit test");
println("if ( " + cnt + ">=1 && " + predictExit + ") break " + label + ";");
}
JavaBlockFinishingInfo howToFinish = genCommonBlock(blk, false);
genBlockFinish(
howToFinish,
"if ( " + cnt + ">=1 ) { break " + label + "; } else {" + throwNoViable + "}"
);
println(cnt + "++;");
tabs--;
println("} while (true);");
println("}");
// Restore previous AST generation
currentASTResult = saveCurrentASTResult;
}
/** Generate the parser Java file */
public void gen(ParserGrammar g) throws IOException {
// if debugging, set up a new vector to keep track of sempred
// strings for this grammar
if (g.debuggingOutput)
semPreds = new Vector();
setGrammar(g);
if (!(grammar instanceof ParserGrammar)) {
antlrTool.panic("Internal error generating parser");
}
// Open the output stream for the parser and set the currentOutput
// SAS: moved file setup so subclass could do it (for VAJ interface)
setupOutput(grammar.getClassName());
genAST = grammar.buildAST;
tabs = 0;
// Generate the header common to all output files.
genHeader();
// Do not use printAction because we assume tabs==0
println(behavior.getHeaderAction(""));
// Generate header for the parser
println("import antlr.TokenBuffer;");
println("import antlr.TokenStreamException;");
println("import antlr.TokenStreamIOException;");
println("import antlr.ANTLRException;");
println("import antlr." + grammar.getSuperClass() + ";");
println("import antlr.Token;");
println("import antlr.TokenStream;");
println("import antlr.RecognitionException;");
println("import antlr.NoViableAltException;");
println("import antlr.MismatchedTokenException;");
println("import antlr.SemanticException;");
println("import antlr.ParserSharedInputState;");
println("import antlr.collections.impl.BitSet;");
if ( genAST ) {
println("import antlr.collections.AST;");
println("import java.util.Hashtable;");
println("import antlr.ASTFactory;");
println("import antlr.ASTPair;");
println("import antlr.collections.impl.ASTArray;");
}
// Output the user-defined parser preamble
println(grammar.preambleAction.getText());
// Generate parser class definition
String sup = null;
if (grammar.superClass != null)
sup = grammar.superClass;
else
sup = "antlr." + grammar.getSuperClass();
// print javadoc comment if any
if (grammar.comment != null) {
_println(grammar.comment);
}
// get prefix (replaces "public" and lets user specify)
String prefix = "public";
Token tprefix = (Token)grammar.options.get("classHeaderPrefix");
if (tprefix != null) {
String p = StringUtils.stripFrontBack(tprefix.getText(), "\"", "\"");
if (p != null) {
prefix = p;
}
}
print(prefix+" ");
print("class " + grammar.getClassName() + " extends " + sup);
println(" implements " + grammar.tokenManager.getName() + TokenTypesFileSuffix);
Token tsuffix = (Token)grammar.options.get("classHeaderSuffix");
if (tsuffix != null) {
String suffix = StringUtils.stripFrontBack(tsuffix.getText(), "\"", "\"");
if (suffix != null)
print(", " + suffix); // must be an interface name for Java
}
println(" {");
// set up an array of all the rule names so the debugger can
// keep track of them only by number -- less to store in tree...
if (grammar.debuggingOutput) {
println("private static final String _ruleNames[] = {");
Enumeration ids = grammar.rules.elements();
int ruleNum = 0;
while (ids.hasMoreElements()) {
GrammarSymbol sym = (GrammarSymbol)ids.nextElement();
if (sym instanceof RuleSymbol)
println(" \"" + ((RuleSymbol)sym).getId() + "\",");
}
println("};");
}
// Generate user-defined parser class members
print(
processActionForSpecialSymbols(grammar.classMemberAction.getText(), grammar.classMemberAction.getLine(), currentRule, null)
);
// Generate parser class constructor from TokenBuffer
println("");
println("protected " + grammar.getClassName() + "(TokenBuffer tokenBuf, int k) {");
println(" super(tokenBuf,k);");
println(" tokenNames = _tokenNames;");
// if debugging, set up arrays and call the user-overridable
// debugging setup method
if (grammar.debuggingOutput) {
println(" ruleNames = _ruleNames;");
println(" semPredNames = _semPredNames;");
println(" setupDebugging(tokenBuf);");
}
if ( grammar.buildAST ) {
println(" buildTokenTypeASTClassMap();");
println(" astFactory = new ASTFactory(getTokenTypeToASTClassMap());");
}
println("}");
println("");
println("public " + grammar.getClassName() + "(TokenBuffer tokenBuf) {");
println(" this(tokenBuf," + grammar.maxk + ");");
println("}");
println("");
// Generate parser class constructor from TokenStream
println("protected " + grammar.getClassName() + "(TokenStream lexer, int k) {");
println(" super(lexer,k);");
println(" tokenNames = _tokenNames;");
// if debugging, set up arrays and call the user-overridable
// debugging setup method
if (grammar.debuggingOutput) {
println(" ruleNames = _ruleNames;");
println(" semPredNames = _semPredNames;");
println(" setupDebugging(lexer);");
}
if ( grammar.buildAST ) {
println(" buildTokenTypeASTClassMap();");
println(" astFactory = new ASTFactory(getTokenTypeToASTClassMap());");
}
println("}");
println("");
println("public " + grammar.getClassName() + "(TokenStream lexer) {");
println(" this(lexer," + grammar.maxk + ");");
println("}");
println("");
println("public " + grammar.getClassName() + "(ParserSharedInputState state) {");
println(" super(state," + grammar.maxk + ");");
println(" tokenNames = _tokenNames;");
if ( grammar.buildAST ) {
println(" buildTokenTypeASTClassMap();");
println(" astFactory = new ASTFactory(getTokenTypeToASTClassMap());");
}
println("}");
println("");
// Generate code for each rule in the grammar
Enumeration ids = grammar.rules.elements();
int ruleNum = 0;
while (ids.hasMoreElements()) {
GrammarSymbol sym = (GrammarSymbol)ids.nextElement();
if (sym instanceof RuleSymbol) {
RuleSymbol rs = (RuleSymbol)sym;
genRule(rs, rs.references.size() == 0, ruleNum++);
}
exitIfError();
}
// Generate the token names
genTokenStrings();
if ( grammar.buildAST ) {
genTokenASTNodeMap();
}
// Generate the bitsets used throughout the grammar
genBitsets(bitsetsUsed, grammar.tokenManager.maxTokenType());
// Generate the semantic predicate map for debugging
if (grammar.debuggingOutput)
genSemPredMap();
// Close class definition
println("");
println("}");
// Close the parser output stream
currentOutput.close();
currentOutput = null;
}
/** Generate code for the given grammar element.
* @param blk The rule-reference to generate
*/
public void gen(RuleRefElement rr) {
if (DEBUG_CODE_GENERATOR) System.out.println("genRR(" + rr + ")");
RuleSymbol rs = (RuleSymbol)grammar.getSymbol(rr.targetRule);
if (rs == null || !rs.isDefined()) {
// Is this redundant???
antlrTool.error("Rule '" + rr.targetRule + "' is not defined", grammar.getFilename(), rr.getLine(), rr.getColumn());
return;
}
if (!(rs instanceof RuleSymbol)) {
// Is this redundant???
antlrTool.error("'" + rr.targetRule + "' does not name a grammar rule", grammar.getFilename(), rr.getLine(), rr.getColumn());
return;
}
genErrorTryForElement(rr);
// AST value for labeled rule refs in tree walker.
// This is not AST construction; it is just the input tree node value.
if (grammar instanceof TreeWalkerGrammar &&
rr.getLabel() != null &&
syntacticPredLevel == 0) {
println(rr.getLabel() + " = _t==ASTNULL ? null : " + lt1Value + ";");
}
// if in lexer and ! on rule ref or alt or rule, save buffer index to kill later
if (grammar instanceof LexerGrammar && (!saveText || rr.getAutoGenType() == GrammarElement.AUTO_GEN_BANG)) {
println("_saveIndex=text.length();");
}
// Process return value assignment if any
printTabs();
if (rr.idAssign != null) {
// Warn if the rule has no return type
if (rs.block.returnAction == null) {
antlrTool.warning("Rule '" + rr.targetRule + "' has no return type", grammar.getFilename(), rr.getLine(), rr.getColumn());
}
_print(rr.idAssign + "=");
}
else {
// Warn about return value if any, but not inside syntactic predicate
if (!(grammar instanceof LexerGrammar) && syntacticPredLevel == 0 && rs.block.returnAction != null) {
antlrTool.warning("Rule '" + rr.targetRule + "' returns a value", grammar.getFilename(), rr.getLine(), rr.getColumn());
}
}
// Call the rule
GenRuleInvocation(rr);
// if in lexer and ! on element or alt or rule, save buffer index to kill later
if (grammar instanceof LexerGrammar && (!saveText || rr.getAutoGenType() == GrammarElement.AUTO_GEN_BANG)) {
println("text.setLength(_saveIndex);");
}
// if not in a syntactic predicate
if (syntacticPredLevel == 0) {
boolean doNoGuessTest = (
grammar.hasSyntacticPredicate &&
(
grammar.buildAST && rr.getLabel() != null ||
(genAST && rr.getAutoGenType() == GrammarElement.AUTO_GEN_NONE)
)
);
if (doNoGuessTest) {
// println("if (inputState.guessing==0) {");
// tabs++;
}
if (grammar.buildAST && rr.getLabel() != null) {
// always gen variable for rule return on labeled rules
println(rr.getLabel() + "_AST = (" + labeledElementASTType + ")returnAST;");
}
if (genAST) {
switch (rr.getAutoGenType()) {
case GrammarElement.AUTO_GEN_NONE:
// println("theASTFactory.addASTChild(currentAST, returnAST);");
println("astFactory.addASTChild(currentAST, returnAST);");
break;
case GrammarElement.AUTO_GEN_CARET:
antlrTool.error("Internal: encountered ^ after rule reference");
break;
default:
break;
}
}
// if a lexer and labeled, Token label defined at rule level, just set it here
if (grammar instanceof LexerGrammar && rr.getLabel() != null) {
println(rr.getLabel() + "=_returnToken;");
}
if (doNoGuessTest) {
// tabs--;
// println("}");
}
}
genErrorCatchForElement(rr);
}
/** Generate code for the given grammar element.
* @param blk The string-literal reference to generate
*/
public void gen(StringLiteralElement atom) {
if (DEBUG_CODE_GENERATOR) System.out.println("genString(" + atom + ")");
// Variable declarations for labeled elements
if (atom.getLabel() != null && syntacticPredLevel == 0) {
println(atom.getLabel() + " = " + lt1Value + ";");
}
// AST
genElementAST(atom);
// is there a bang on the literal?
boolean oldsaveText = saveText;
saveText = saveText && atom.getAutoGenType() == GrammarElement.AUTO_GEN_NONE;
// matching
genMatch(atom);
saveText = oldsaveText;
// tack on tree cursor motion if doing a tree walker
if (grammar instanceof TreeWalkerGrammar) {
println("_t = _t.getNextSibling();");
}
}
/** Generate code for the given grammar element.
* @param blk The token-range reference to generate
*/
public void gen(TokenRangeElement r) {
genErrorTryForElement(r);
if (r.getLabel() != null && syntacticPredLevel == 0) {
println(r.getLabel() + " = " + lt1Value + ";");
}
// AST
genElementAST(r);
// match
println("matchRange(" + r.beginText + "," + r.endText + ");");
genErrorCatchForElement(r);
}
/** Generate code for the given grammar element.
* @param blk The token-reference to generate
*/
public void gen(TokenRefElement atom) {
if (DEBUG_CODE_GENERATOR) System.out.println("genTokenRef(" + atom + ")");
if (grammar instanceof LexerGrammar) {
antlrTool.panic("Token reference found in lexer");
}
genErrorTryForElement(atom);
// Assign Token value to token label variable
if (atom.getLabel() != null && syntacticPredLevel == 0) {
println(atom.getLabel() + " = " + lt1Value + ";");
}
// AST
genElementAST(atom);
// matching
genMatch(atom);
genErrorCatchForElement(atom);
// tack on tree cursor motion if doing a tree walker
if (grammar instanceof TreeWalkerGrammar) {
println("_t = _t.getNextSibling();");
}
}
public void gen(TreeElement t) {
// save AST cursor
println("AST __t" + t.ID + " = _t;");
// If there is a label on the root, then assign that to the variable
if (t.root.getLabel() != null) {
println(t.root.getLabel() + " = _t==ASTNULL ? null :(" + labeledElementASTType + ")_t;");
}
// check for invalid modifiers ! and ^ on tree element roots
if ( t.root.getAutoGenType() == GrammarElement.AUTO_GEN_BANG ) {
antlrTool.error("Suffixing a root node with '!' is not implemented",
grammar.getFilename(), t.getLine(), t.getColumn());
t.root.setAutoGenType(GrammarElement.AUTO_GEN_NONE);
}
if ( t.root.getAutoGenType() == GrammarElement.AUTO_GEN_CARET ) {
antlrTool.warning("Suffixing a root node with '^' is redundant; already a root",
grammar.getFilename(), t.getLine(), t.getColumn());
t.root.setAutoGenType(GrammarElement.AUTO_GEN_NONE);
}
// Generate AST variables
genElementAST(t.root);
if (grammar.buildAST) {
// Save the AST construction state
println("ASTPair __currentAST" + t.ID + " = currentAST.copy();");
// Make the next item added a child of the TreeElement root
println("currentAST.root = currentAST.child;");
println("currentAST.child = null;");
}
// match root
if ( t.root instanceof WildcardElement ) {
println("if ( _t==null ) throw new MismatchedTokenException();");
}
else {
genMatch(t.root);
}
// move to list of children
println("_t = _t.getFirstChild();");
// walk list of children, generating code for each
for (int i = 0; i < t.getAlternatives().size(); i++) {
Alternative a = t.getAlternativeAt(i);
AlternativeElement e = a.head;
while (e != null) {
e.generate();
e = e.next;
}
}
if (grammar.buildAST) {
// restore the AST construction state to that just after the
// tree root was added
println("currentAST = __currentAST" + t.ID + ";");
}
// restore AST cursor
println("_t = __t" + t.ID + ";");
// move cursor to sibling of tree just parsed
println("_t = _t.getNextSibling();");
}
/** Generate the tree-parser Java file */
public void gen(TreeWalkerGrammar g) throws IOException {
// SAS: debugging stuff removed for now...
setGrammar(g);
if (!(grammar instanceof TreeWalkerGrammar)) {
antlrTool.panic("Internal error generating tree-walker");
}
// Open the output stream for the parser and set the currentOutput
// SAS: move file open to method so subclass can override it
// (mainly for VAJ interface)
setupOutput(grammar.getClassName());
genAST = grammar.buildAST;
tabs = 0;
// Generate the header common to all output files.
genHeader();
// Do not use printAction because we assume tabs==0
println(behavior.getHeaderAction(""));
// Generate header for the parser
println("import antlr." + grammar.getSuperClass() + ";");
println("import antlr.Token;");
println("import antlr.collections.AST;");
println("import antlr.RecognitionException;");
println("import antlr.ANTLRException;");
println("import antlr.NoViableAltException;");
println("import antlr.MismatchedTokenException;");
println("import antlr.SemanticException;");
println("import antlr.collections.impl.BitSet;");
println("import antlr.ASTPair;");
println("import antlr.collections.impl.ASTArray;");
// Output the user-defined parser premamble
println(grammar.preambleAction.getText());
// Generate parser class definition
String sup = null;
if (grammar.superClass != null) {
sup = grammar.superClass;
}
else {
sup = "antlr." + grammar.getSuperClass();
}
println("");
// print javadoc comment if any
if (grammar.comment != null) {
_println(grammar.comment);
}
// get prefix (replaces "public" and lets user specify)
String prefix = "public";
Token tprefix = (Token)grammar.options.get("classHeaderPrefix");
if (tprefix != null) {
String p = StringUtils.stripFrontBack(tprefix.getText(), "\"", "\"");
if (p != null) {
prefix = p;
}
}
print(prefix+" ");
print("class " + grammar.getClassName() + " extends " + sup);
println(" implements " + grammar.tokenManager.getName() + TokenTypesFileSuffix);
Token tsuffix = (Token)grammar.options.get("classHeaderSuffix");
if (tsuffix != null) {
String suffix = StringUtils.stripFrontBack(tsuffix.getText(), "\"", "\"");
if (suffix != null) {
print(", " + suffix); // must be an interface name for Java
}
}
println(" {");
// Generate user-defined parser class members
print(
processActionForSpecialSymbols(grammar.classMemberAction.getText(), grammar.classMemberAction.getLine(), currentRule, null)
);
// Generate default parser class constructor
println("public " + grammar.getClassName() + "() {");
tabs++;
println("tokenNames = _tokenNames;");
tabs--;
println("}");
println("");
// Generate code for each rule in the grammar
Enumeration ids = grammar.rules.elements();
int ruleNum = 0;
String ruleNameInits = "";
while (ids.hasMoreElements()) {
GrammarSymbol sym = (GrammarSymbol)ids.nextElement();
if (sym instanceof RuleSymbol) {
RuleSymbol rs = (RuleSymbol)sym;
genRule(rs, rs.references.size() == 0, ruleNum++);
}
exitIfError();
}
// Generate the token names
genTokenStrings();
// Generate the bitsets used throughout the grammar
genBitsets(bitsetsUsed, grammar.tokenManager.maxTokenType());
// Close class definition
println("}");
println("");
// Close the parser output stream
currentOutput.close();
currentOutput = null;
}
/** Generate code for the given grammar element.
* @param wc The wildcard element to generate
*/
public void gen(WildcardElement wc) {
// Variable assignment for labeled elements
if (wc.getLabel() != null && syntacticPredLevel == 0) {
println(wc.getLabel() + " = " + lt1Value + ";");
}
// AST
genElementAST(wc);
// Match anything but EOF
if (grammar instanceof TreeWalkerGrammar) {
println("if ( _t==null ) throw new MismatchedTokenException();");
}
else if (grammar instanceof LexerGrammar) {
if (grammar instanceof LexerGrammar &&
(!saveText || wc.getAutoGenType() == GrammarElement.AUTO_GEN_BANG)) {
println("_saveIndex=text.length();");
}
println("matchNot(EOF_CHAR);");
if (grammar instanceof LexerGrammar &&
(!saveText || wc.getAutoGenType() == GrammarElement.AUTO_GEN_BANG)) {
println("text.setLength(_saveIndex);"); // kill text atom put in buffer
}
}
else {
println("matchNot(" + getValueString(Token.EOF_TYPE) + ");");
}
// tack on tree cursor motion if doing a tree walker
if (grammar instanceof TreeWalkerGrammar) {
println("_t = _t.getNextSibling();");
}
}
/** Generate code for the given grammar element.
* @param blk The (...)* block to generate
*/
public void gen(ZeroOrMoreBlock blk) {
if (DEBUG_CODE_GENERATOR) System.out.println("gen*(" + blk + ")");
println("{");
genBlockPreamble(blk);
String label;
if (blk.getLabel() != null) {
label = blk.getLabel();
}
else {
label = "_loop" + blk.ID;
}
println(label + ":");
println("do {");
tabs++;
// generate the init action for ()* inside the loop
// this allows us to do usefull EOF checking...
genBlockInitAction(blk);
// Tell AST generation to build subrule result
String saveCurrentASTResult = currentASTResult;
if (blk.getLabel() != null) {
currentASTResult = blk.getLabel();
}
boolean ok = grammar.theLLkAnalyzer.deterministic(blk);
// generate exit test if greedy set to false
// and an alt is ambiguous with exit branch
// or when lookahead derived purely from end-of-file
// Lookahead analysis stops when end-of-file is hit,
// returning set {epsilon}. Since {epsilon} is not
// ambig with any real tokens, no error is reported
// by deterministic() routines and we have to check
// for the case where the lookahead depth didn't get
// set to NONDETERMINISTIC (this only happens when the
// FOLLOW contains real atoms + epsilon).
boolean generateNonGreedyExitPath = false;
int nonGreedyExitDepth = grammar.maxk;
if (!blk.greedy &&
blk.exitLookaheadDepth <= grammar.maxk &&
blk.exitCache[blk.exitLookaheadDepth].containsEpsilon()) {
generateNonGreedyExitPath = true;
nonGreedyExitDepth = blk.exitLookaheadDepth;
}
else if (!blk.greedy &&
blk.exitLookaheadDepth == LLkGrammarAnalyzer.NONDETERMINISTIC) {
generateNonGreedyExitPath = true;
}
if (generateNonGreedyExitPath) {
if (DEBUG_CODE_GENERATOR) {
System.out.println("nongreedy (...)* loop; exit depth is " +
blk.exitLookaheadDepth);
}
String predictExit =
getLookaheadTestExpression(blk.exitCache,
nonGreedyExitDepth);
println("// nongreedy exit test");
println("if (" + predictExit + ") break " + label + ";");
}
JavaBlockFinishingInfo howToFinish = genCommonBlock(blk, false);
genBlockFinish(howToFinish, "break " + label + ";");
tabs--;
println("} while (true);");
println("}");
// Restore previous AST generation
currentASTResult = saveCurrentASTResult;
}
/** Generate an alternative.
* @param alt The alternative to generate
* @param blk The block to which the alternative belongs
*/
protected void genAlt(Alternative alt, AlternativeBlock blk) {
// Save the AST generation state, and set it to that of the alt
boolean savegenAST = genAST;
genAST = genAST && alt.getAutoGen();
boolean oldsaveTest = saveText;
saveText = saveText && alt.getAutoGen();
// Reset the variable name map for the alternative
Hashtable saveMap = treeVariableMap;
treeVariableMap = new Hashtable();
// Generate try block around the alt for error handling
if (alt.exceptionSpec != null) {
println("try { // for error handling");
tabs++;
}
AlternativeElement elem = alt.head;
while (!(elem instanceof BlockEndElement)) {
elem.generate(); // alt can begin with anything. Ask target to gen.
elem = elem.next;
}
if (genAST) {
if (blk instanceof RuleBlock) {
// Set the AST return value for the rule
RuleBlock rblk = (RuleBlock)blk;
if (grammar.hasSyntacticPredicate) {
// println("if ( inputState.guessing==0 ) {");
// tabs++;
}
println(rblk.getRuleName() + "_AST = (" + labeledElementASTType + ")currentAST.root;");
if (grammar.hasSyntacticPredicate) {
// --tabs;
// println("}");
}
}
else if (blk.getLabel() != null) {
// ### future: also set AST value for labeled subrules.
// println(blk.getLabel() + "_AST = ("+labeledElementASTType+")currentAST.root;");
antlrTool.warning("Labeled subrules not yet supported", grammar.getFilename(), blk.getLine(), blk.getColumn());
}
}
if (alt.exceptionSpec != null) {
// close try block
tabs--;
println("}");
genErrorHandler(alt.exceptionSpec);
}
genAST = savegenAST;
saveText = oldsaveTest;
treeVariableMap = saveMap;
}
/** Generate all the bitsets to be used in the parser or lexer
* Generate the raw bitset data like "long _tokenSet1_data[] = {...};"
* and the BitSet object declarations like "BitSet _tokenSet1 = new BitSet(_tokenSet1_data);"
* Note that most languages do not support object initialization inside a
* class definition, so other code-generators may have to separate the
* bitset declarations from the initializations (e.g., put the initializations
* in the generated constructor instead).
* @param bitsetList The list of bitsets to generate.
* @param maxVocabulary Ensure that each generated bitset can contain at least this value.
*/
protected void genBitsets(Vector bitsetList,
int maxVocabulary
) {
println("");
for (int i = 0; i < bitsetList.size(); i++) {
BitSet p = (BitSet)bitsetList.elementAt(i);
// Ensure that generated BitSet is large enough for vocabulary
p.growToInclude(maxVocabulary);
genBitSet(p, i);
}
}
/** Do something simple like:
* private static final long[] mk_tokenSet_0() {
* long[] data = { -2305839160922996736L, 63L, 16777216L, 0L, 0L, 0L };
* return data;
* }
* public static final BitSet _tokenSet_0 = new BitSet(mk_tokenSet_0());
*
* Or, for large bitsets, optimize init so ranges are collapsed into loops.
* This is most useful for lexers using unicode.
*/
private void genBitSet(BitSet p, int id) {
// initialization data
println(
"private static final long[] mk" + getBitsetName(id) + "() {"
);
int n = p.lengthInLongWords();
if ( n<BITSET_OPTIMIZE_INIT_THRESHOLD ) {
println("\tlong[] data = { " + p.toStringOfWords() + "};");
}
else {
// will init manually, allocate space then set values
println("\tlong[] data = new long["+n+"];");
long[] elems = p.toPackedArray();
for (int i = 0; i < elems.length;) {
if ( elems[i]==0 ) {
// done automatically by Java, don't waste time/code
i++;
continue;
}
if ( (i+1)==elems.length || elems[i]!=elems[i+1] ) {
// last number or no run of numbers, just dump assignment
println("\tdata["+i+"]="+elems[i]+"L;");
i++;
}
else {
// scan to find end of run
int j;
for (j = i + 1;
j < elems.length && elems[j]==elems[i];
j++)
{
}
// j-1 is last member of run
println("\tfor (int i = "+i+"; i<="+(j-1)+"; i++) { data[i]="+
elems[i]+"L; }");
i = j;
}
}
}
println("\treturn data;");
println("}");
// BitSet object
println(
"public static final BitSet " + getBitsetName(id) + " = new BitSet(" +
"mk" + getBitsetName(id) + "()" +
");"
);
}
/** Generate the finish of a block, using a combination of the info
* returned from genCommonBlock() and the action to perform when
* no alts were taken
* @param howToFinish The return of genCommonBlock()
* @param noViableAction What to generate when no alt is taken
*/
private void genBlockFinish(JavaBlockFinishingInfo howToFinish, String noViableAction) {
if (howToFinish.needAnErrorClause &&
(howToFinish.generatedAnIf || howToFinish.generatedSwitch)) {
if (howToFinish.generatedAnIf) {
println("else {");
}
else {
println("{");
}
tabs++;
println(noViableAction);
tabs--;
println("}");
}
if (howToFinish.postscript != null) {
println(howToFinish.postscript);
}
}
/** Generate the init action for a block, which may be a RuleBlock or a
* plain AlternativeBLock.
* @blk The block for which the preamble is to be generated.
*/
protected void genBlockInitAction(AlternativeBlock blk) {
// dump out init action
if (blk.initAction != null) {
printAction(processActionForSpecialSymbols(blk.initAction, blk.getLine(), currentRule, null));
}
}
/** Generate the header for a block, which may be a RuleBlock or a
* plain AlternativeBLock. This generates any variable declarations
* and syntactic-predicate-testing variables.
* @blk The block for which the preamble is to be generated.
*/
protected void genBlockPreamble(AlternativeBlock blk) {
// define labels for rule blocks.
if (blk instanceof RuleBlock) {
RuleBlock rblk = (RuleBlock)blk;
if (rblk.labeledElements != null) {
for (int i = 0; i < rblk.labeledElements.size(); i++) {
AlternativeElement a = (AlternativeElement)rblk.labeledElements.elementAt(i);
// System.out.println("looking at labeled element: "+a);
// Variables for labeled rule refs and
// subrules are different than variables for
// grammar atoms. This test is a little tricky
// because we want to get all rule refs and ebnf,
// but not rule blocks or syntactic predicates
if (
a instanceof RuleRefElement ||
a instanceof AlternativeBlock &&
!(a instanceof RuleBlock) &&
!(a instanceof SynPredBlock)
) {
if (
!(a instanceof RuleRefElement) &&
((AlternativeBlock)a).not &&
analyzer.subruleCanBeInverted(((AlternativeBlock)a), grammar instanceof LexerGrammar)
) {
// Special case for inverted subrules that
// will be inlined. Treat these like
// token or char literal references
println(labeledElementType + " " + a.getLabel() + " = " + labeledElementInit + ";");
if (grammar.buildAST) {
genASTDeclaration(a);
}
}
else {
if (grammar.buildAST) {
// Always gen AST variables for
// labeled elements, even if the
// element itself is marked with !
genASTDeclaration(a);
}
if (grammar instanceof LexerGrammar) {
println("Token " + a.getLabel() + "=null;");
}
if (grammar instanceof TreeWalkerGrammar) {
// always generate rule-ref variables
// for tree walker
println(labeledElementType + " " + a.getLabel() + " = " + labeledElementInit + ";");
}
}
}
else {
// It is a token or literal reference. Generate the
// correct variable type for this grammar
println(labeledElementType + " " + a.getLabel() + " = " + labeledElementInit + ";");
// In addition, generate *_AST variables if
// building ASTs
if (grammar.buildAST) {
if (a instanceof GrammarAtom &&
((GrammarAtom)a).getASTNodeType() != null) {
GrammarAtom ga = (GrammarAtom)a;
genASTDeclaration(a, ga.getASTNodeType());
}
else {
genASTDeclaration(a);
}
}
}
}
}
}
}
/** Generate a series of case statements that implement a BitSet test.
* @param p The Bitset for which cases are to be generated
*/
protected void genCases(BitSet p) {
if (DEBUG_CODE_GENERATOR) System.out.println("genCases(" + p + ")");
int[] elems;
elems = p.toArray();
// Wrap cases four-per-line for lexer, one-per-line for parser
int wrap = (grammar instanceof LexerGrammar) ? 4 : 1;
int j = 1;
boolean startOfLine = true;
for (int i = 0; i < elems.length; i++) {
if (j == 1) {
print("");
}
else {
_print(" ");
}
_print("case " + getValueString(elems[i]) + ":");
if (j == wrap) {
_println("");
startOfLine = true;
j = 1;
}
else {
j++;
startOfLine = false;
}
}
if (!startOfLine) {
_println("");
}
}
/**Generate common code for a block of alternatives; return a
* postscript that needs to be generated at the end of the
* block. Other routines may append else-clauses and such for
* error checking before the postfix is generated. If the
* grammar is a lexer, then generate alternatives in an order
* where alternatives requiring deeper lookahead are generated
* first, and EOF in the lookahead set reduces the depth of
* the lookahead. @param blk The block to generate @param
* noTestForSingle If true, then it does not generate a test
* for a single alternative.
*/
public JavaBlockFinishingInfo genCommonBlock(AlternativeBlock blk,
boolean noTestForSingle) {
int nIF = 0;
boolean createdLL1Switch = false;
int closingBracesOfIFSequence = 0;
JavaBlockFinishingInfo finishingInfo = new JavaBlockFinishingInfo();
if (DEBUG_CODE_GENERATOR) System.out.println("genCommonBlock(" + blk + ")");
// Save the AST generation state, and set it to that of the block
boolean savegenAST = genAST;
genAST = genAST && blk.getAutoGen();
boolean oldsaveTest = saveText;
saveText = saveText && blk.getAutoGen();
// Is this block inverted? If so, generate special-case code
if (
blk.not &&
analyzer.subruleCanBeInverted(blk, grammar instanceof LexerGrammar)
) {
if (DEBUG_CODE_GENERATOR) System.out.println("special case: ~(subrule)");
Lookahead p = analyzer.look(1, blk);
// Variable assignment for labeled elements
if (blk.getLabel() != null && syntacticPredLevel == 0) {
println(blk.getLabel() + " = " + lt1Value + ";");
}
// AST
genElementAST(blk);
String astArgs = "";
if (grammar instanceof TreeWalkerGrammar) {
astArgs = "_t,";
}
// match the bitset for the alternative
println("match(" + astArgs + getBitsetName(markBitsetForGen(p.fset)) + ");");
// tack on tree cursor motion if doing a tree walker
if (grammar instanceof TreeWalkerGrammar) {
println("_t = _t.getNextSibling();");
}
return finishingInfo;
}
// Special handling for single alt
if (blk.getAlternatives().size() == 1) {
Alternative alt = blk.getAlternativeAt(0);
// Generate a warning if there is a synPred for single alt.
if (alt.synPred != null) {
antlrTool.warning(
"Syntactic predicate superfluous for single alternative",
grammar.getFilename(),
blk.getAlternativeAt(0).synPred.getLine(),
blk.getAlternativeAt(0).synPred.getColumn()
);
}
if (noTestForSingle) {
if (alt.semPred != null) {
// Generate validating predicate
genSemPred(alt.semPred, blk.line);
}
genAlt(alt, blk);
return finishingInfo;
}
}
// count number of simple LL(1) cases; only do switch for
// many LL(1) cases (no preds, no end of token refs)
// We don't care about exit paths for (...)*, (...)+
// because we don't explicitly have a test for them
// as an alt in the loop.
//
// Also, we now count how many unicode lookahead sets
// there are--they must be moved to DEFAULT or ELSE
// clause.
int nLL1 = 0;
for (int i = 0; i < blk.getAlternatives().size(); i++) {
Alternative a = blk.getAlternativeAt(i);
if (suitableForCaseExpression(a)) {
nLL1++;
}
}
// do LL(1) cases
if (nLL1 >= makeSwitchThreshold) {
// Determine the name of the item to be compared
String testExpr = lookaheadString(1);
createdLL1Switch = true;
// when parsing trees, convert null to valid tree node with NULL lookahead
if (grammar instanceof TreeWalkerGrammar) {
println("if (_t==null) _t=ASTNULL;");
}
println("switch ( " + testExpr + ") {");
for (int i = 0; i < blk.alternatives.size(); i++) {
Alternative alt = blk.getAlternativeAt(i);
// ignore any non-LL(1) alts, predicated alts,
// or end-of-token alts for case expressions
if (!suitableForCaseExpression(alt)) {
continue;
}
Lookahead p = alt.cache[1];
if (p.fset.degree() == 0 && !p.containsEpsilon()) {
antlrTool.warning("Alternate omitted due to empty prediction set",
grammar.getFilename(),
alt.head.getLine(), alt.head.getColumn());
}
else {
genCases(p.fset);
println("{");
tabs++;
genAlt(alt, blk);
println("break;");
tabs--;
println("}");
}
}
println("default:");
tabs++;
}
// do non-LL(1) and nondeterministic cases This is tricky in
// the lexer, because of cases like: STAR : '*' ; ASSIGN_STAR
// : "*="; Since nextToken is generated without a loop, then
// the STAR will have end-of-token as it's lookahead set for
// LA(2). So, we must generate the alternatives containing
// trailing end-of-token in their lookahead sets *after* the
// alternatives without end-of-token. This implements the
// usual lexer convention that longer matches come before
// shorter ones, e.g. "*=" matches ASSIGN_STAR not STAR
//
// For non-lexer grammars, this does not sort the alternates
// by depth Note that alts whose lookahead is purely
// end-of-token at k=1 end up as default or else clauses.
int startDepth = (grammar instanceof LexerGrammar) ? grammar.maxk : 0;
for (int altDepth = startDepth; altDepth >= 0; altDepth--) {
if (DEBUG_CODE_GENERATOR) System.out.println("checking depth " + altDepth);
for (int i = 0; i < blk.alternatives.size(); i++) {
Alternative alt = blk.getAlternativeAt(i);
if (DEBUG_CODE_GENERATOR) System.out.println("genAlt: " + i);
// if we made a switch above, ignore what we already took care
// of. Specifically, LL(1) alts with no preds
// that do not have end-of-token in their prediction set
// and that are not giant unicode sets.
if (createdLL1Switch && suitableForCaseExpression(alt)) {
if (DEBUG_CODE_GENERATOR) System.out.println("ignoring alt because it was in the switch");
continue;
}
String e;
boolean unpredicted = false;
if (grammar instanceof LexerGrammar) {
// Calculate the "effective depth" of the alt,
// which is the max depth at which
// cache[depth]!=end-of-token
int effectiveDepth = alt.lookaheadDepth;
if (effectiveDepth == GrammarAnalyzer.NONDETERMINISTIC) {
// use maximum lookahead
effectiveDepth = grammar.maxk;
}
while (effectiveDepth >= 1 &&
alt.cache[effectiveDepth].containsEpsilon()) {
effectiveDepth--;
}
// Ignore alts whose effective depth is other than
// the ones we are generating for this iteration.
if (effectiveDepth != altDepth) {
if (DEBUG_CODE_GENERATOR)
System.out.println("ignoring alt because effectiveDepth!=altDepth;" + effectiveDepth + "!=" + altDepth);
continue;
}
unpredicted = lookaheadIsEmpty(alt, effectiveDepth);
e = getLookaheadTestExpression(alt, effectiveDepth);
}
else {
unpredicted = lookaheadIsEmpty(alt, grammar.maxk);
e = getLookaheadTestExpression(alt, grammar.maxk);
}
// Was it a big unicode range that forced unsuitability
// for a case expression?
if (alt.cache[1].fset.degree() > caseSizeThreshold &&
suitableForCaseExpression(alt)) {
if (nIF == 0) {
println("if " + e + " {");
}
else {
println("else if " + e + " {");
}
}
else if (unpredicted &&
alt.semPred == null &&
alt.synPred == null) {
// The alt has empty prediction set and no
// predicate to help out. if we have not
// generated a previous if, just put {...} around
// the end-of-token clause
if (nIF == 0) {
println("{");
}
else {
println("else {");
}
finishingInfo.needAnErrorClause = false;
}
else { // check for sem and syn preds
// Add any semantic predicate expression to the
// lookahead test
if (alt.semPred != null) {
// if debugging, wrap the evaluation of the
// predicate in a method translate $ and #
// references
ActionTransInfo tInfo = new ActionTransInfo();
String actionStr =
processActionForSpecialSymbols(alt.semPred,
blk.line,
currentRule,
tInfo);
// ignore translation info...we don't need to
// do anything with it. call that will inform
// SemanticPredicateListeners of the result
if (((grammar instanceof ParserGrammar) ||
(grammar instanceof LexerGrammar)) &&
grammar.debuggingOutput) {
e = "(" + e + "&& fireSemanticPredicateEvaluated(antlr.debug.SemanticPredicateEvent.PREDICTING," +
addSemPred(charFormatter.escapeString(actionStr)) + "," + actionStr + "))";
}
else {
e = "(" + e + "&&(" + actionStr + "))";
}
}
// Generate any syntactic predicates
if (nIF > 0) {
if (alt.synPred != null) {
println("else {");
tabs++;
genSynPred(alt.synPred, e);
closingBracesOfIFSequence++;
}
else {
println("else if " + e + " {");
}
}
else {
if (alt.synPred != null) {
genSynPred(alt.synPred, e);
}
else {
// when parsing trees, convert null to
// valid tree node with NULL lookahead.
if (grammar instanceof TreeWalkerGrammar) {
println("if (_t==null) _t=ASTNULL;");
}
println("if " + e + " {");
}
}
}
nIF++;
tabs++;
genAlt(alt, blk);
tabs--;
println("}");
}
}
String ps = "";
for (int i = 1; i <= closingBracesOfIFSequence; i++) {
ps += "}";
}
// Restore the AST generation state
genAST = savegenAST;
// restore save text state
saveText = oldsaveTest;
// Return the finishing info.
if (createdLL1Switch) {
tabs--;
finishingInfo.postscript = ps + "}";
finishingInfo.generatedSwitch = true;
finishingInfo.generatedAnIf = nIF > 0;
//return new JavaBlockFinishingInfo(ps+"}",true,nIF>0); // close up switch statement
}
else {
finishingInfo.postscript = ps;
finishingInfo.generatedSwitch = false;
finishingInfo.generatedAnIf = nIF > 0;
// return new JavaBlockFinishingInfo(ps, false,nIF>0);
}
return finishingInfo;
}
private static boolean suitableForCaseExpression(Alternative a) {
return
a.lookaheadDepth == 1 &&
a.semPred == null &&
!a.cache[1].containsEpsilon() &&
a.cache[1].fset.degree() <= caseSizeThreshold;
}
/** Generate code to link an element reference into the AST */
private void genElementAST(AlternativeElement el) {
// handle case where you're not building trees, but are in tree walker.
// Just need to get labels set up.
if (grammar instanceof TreeWalkerGrammar && !grammar.buildAST) {
String elementRef;
String astName;
// Generate names and declarations of the AST variable(s)
if (el.getLabel() == null) {
elementRef = lt1Value;
// Generate AST variables for unlabeled stuff
astName = "tmp" + astVarNumber + "_AST";
astVarNumber++;
// Map the generated AST variable in the alternate
mapTreeVariable(el, astName);
// Generate an "input" AST variable also
println(labeledElementASTType + " " + astName + "_in = " + elementRef + ";");
}
return;
}
if (grammar.buildAST && syntacticPredLevel == 0) {
boolean needASTDecl =
(genAST &&
(el.getLabel() != null ||
el.getAutoGenType() != GrammarElement.AUTO_GEN_BANG
)
);
// RK: if we have a grammar element always generate the decl
// since some guy can access it from an action and we can't
// peek ahead (well not without making a mess).
// I'd prefer taking this out.
if (el.getAutoGenType() != GrammarElement.AUTO_GEN_BANG &&
(el instanceof TokenRefElement))
{
needASTDecl = true;
}
boolean doNoGuessTest =
(grammar.hasSyntacticPredicate && needASTDecl);
String elementRef;
String astNameBase;
// Generate names and declarations of the AST variable(s)
if (el.getLabel() != null) {
elementRef = el.getLabel();
astNameBase = el.getLabel();
}
else {
elementRef = lt1Value;
// Generate AST variables for unlabeled stuff
astNameBase = "tmp" + astVarNumber;
;
astVarNumber++;
}
// Generate the declaration if required.
if (needASTDecl) {
// Generate the declaration
if (el instanceof GrammarAtom) {
GrammarAtom ga = (GrammarAtom)el;
if (ga.getASTNodeType() != null) {
genASTDeclaration(el, astNameBase, ga.getASTNodeType());
// println(ga.getASTNodeType()+" " + astName+" = null;");
}
else {
genASTDeclaration(el, astNameBase, labeledElementASTType);
// println(labeledElementASTType+" " + astName + " = null;");
}
}
else {
genASTDeclaration(el, astNameBase, labeledElementASTType);
// println(labeledElementASTType+" " + astName + " = null;");
}
}
// for convenience..
String astName = astNameBase + "_AST";
// Map the generated AST variable in the alternate
mapTreeVariable(el, astName);
if (grammar instanceof TreeWalkerGrammar) {
// Generate an "input" AST variable also
println(labeledElementASTType + " " + astName + "_in = null;");
}
// Enclose actions with !guessing
if (doNoGuessTest) {
// println("if (inputState.guessing==0) {");
// tabs++;
}
// if something has a label assume it will be used
// so we must initialize the RefAST
if (el.getLabel() != null) {
if (el instanceof GrammarAtom) {
println(astName + " = " + getASTCreateString((GrammarAtom)el, elementRef) + ";");
}
else {
println(astName + " = " + getASTCreateString(elementRef) + ";");
}
}
// if it has no label but a declaration exists initialize it.
if (el.getLabel() == null && needASTDecl) {
elementRef = lt1Value;
if (el instanceof GrammarAtom) {
println(astName + " = " + getASTCreateString((GrammarAtom)el, elementRef) + ";");
}
else {
println(astName + " = " + getASTCreateString(elementRef) + ";");
}
// Map the generated AST variable in the alternate
if (grammar instanceof TreeWalkerGrammar) {
// set "input" AST variable also
println(astName + "_in = " + elementRef + ";");
}
}
if (genAST) {
switch (el.getAutoGenType()) {
case GrammarElement.AUTO_GEN_NONE:
println("astFactory.addASTChild(currentAST, " + astName + ");");
break;
case GrammarElement.AUTO_GEN_CARET:
println("astFactory.makeASTRoot(currentAST, " + astName + ");");
break;
default:
break;
}
}
if (doNoGuessTest) {
// tabs--;
// println("}");
}
}
}
/** Close the try block and generate catch phrases
* if the element has a labeled handler in the rule
*/
private void genErrorCatchForElement(AlternativeElement el) {
if (el.getLabel() == null) return;
String r = el.enclosingRuleName;
if (grammar instanceof LexerGrammar) {
r = CodeGenerator.encodeLexerRuleName(el.enclosingRuleName);
}
RuleSymbol rs = (RuleSymbol)grammar.getSymbol(r);
if (rs == null) {
antlrTool.panic("Enclosing rule not found!");
}
ExceptionSpec ex = rs.block.findExceptionSpec(el.getLabel());
if (ex != null) {
tabs--;
println("}");
genErrorHandler(ex);
}
}
/** Generate the catch phrases for a user-specified error handler */
private void genErrorHandler(ExceptionSpec ex) {
// Each ExceptionHandler in the ExceptionSpec is a separate catch
for (int i = 0; i < ex.handlers.size(); i++) {
ExceptionHandler handler = (ExceptionHandler)ex.handlers.elementAt(i);
// Generate catch phrase
println("catch (" + handler.exceptionTypeAndName.getText() + ") {");
tabs++;
if (grammar.hasSyntacticPredicate) {
println("if (inputState.guessing==0) {");
tabs++;
}
// When not guessing, execute user handler action
ActionTransInfo tInfo = new ActionTransInfo();
printAction(
processActionForSpecialSymbols(handler.action.getText(),
handler.action.getLine(),
currentRule, tInfo)
);
if (grammar.hasSyntacticPredicate) {
tabs--;
println("} else {");
tabs++;
// When guessing, rethrow exception
println(
"throw " +
extractIdOfAction(handler.exceptionTypeAndName) +
";"
);
tabs--;
println("}");
}
// Close catch phrase
tabs--;
println("}");
}
}
/** Generate a try { opening if the element has a labeled handler in the rule */
private void genErrorTryForElement(AlternativeElement el) {
if (el.getLabel() == null) return;
String r = el.enclosingRuleName;
if (grammar instanceof LexerGrammar) {
r = CodeGenerator.encodeLexerRuleName(el.enclosingRuleName);
}
RuleSymbol rs = (RuleSymbol)grammar.getSymbol(r);
if (rs == null) {
antlrTool.panic("Enclosing rule not found!");
}
ExceptionSpec ex = rs.block.findExceptionSpec(el.getLabel());
if (ex != null) {
println("try { // for error handling");
tabs++;
}
}
protected void genASTDeclaration(AlternativeElement el) {
genASTDeclaration(el, labeledElementASTType);
}
protected void genASTDeclaration(AlternativeElement el, String node_type) {
genASTDeclaration(el, el.getLabel(), node_type);
}
protected void genASTDeclaration(AlternativeElement el, String var_name, String node_type) {
// already declared?
if (declaredASTVariables.contains(el))
return;
// emit code
println(node_type + " " + var_name + "_AST = null;");
// mark as declared
declaredASTVariables.add(el);
}
/** Generate a header that is common to all Java files */
protected void genHeader() {
println("// $ANTLR " + Tool.version + ": " +
"\"" + antlrTool.fileMinusPath(antlrTool.grammarFile) + "\"" +
" -> " +
"\"" + grammar.getClassName() + ".java\"$");
}
private void genLiteralsTest() {
println("_ttype = testLiteralsTable(_ttype);");
}
private void genLiteralsTestForPartialToken() {
println("_ttype = testLiteralsTable(new String(text.getBuffer(),_begin,text.length()-_begin),_ttype);");
}
protected void genMatch(BitSet b) {
}
protected void genMatch(GrammarAtom atom) {
if (atom instanceof StringLiteralElement) {
if (grammar instanceof LexerGrammar) {
genMatchUsingAtomText(atom);
}
else {
genMatchUsingAtomTokenType(atom);
}
}
else if (atom instanceof CharLiteralElement) {
if (grammar instanceof LexerGrammar) {
genMatchUsingAtomText(atom);
}
else {
antlrTool.error("cannot ref character literals in grammar: " + atom);
}
}
else if (atom instanceof TokenRefElement) {
genMatchUsingAtomText(atom);
}
else if (atom instanceof WildcardElement) {
gen((WildcardElement)atom);
}
}
protected void genMatchUsingAtomText(GrammarAtom atom) {
// match() for trees needs the _t cursor
String astArgs = "";
if (grammar instanceof TreeWalkerGrammar) {
astArgs = "_t,";
}
// if in lexer and ! on element, save buffer index to kill later
if (grammar instanceof LexerGrammar && (!saveText || atom.getAutoGenType() == GrammarElement.AUTO_GEN_BANG)) {
println("_saveIndex=text.length();");
}
print(atom.not ? "matchNot(" : "match(");
_print(astArgs);
// print out what to match
if (atom.atomText.equals("EOF")) {
// horrible hack to handle EOF case
_print("Token.EOF_TYPE");
}
else {
_print(atom.atomText);
}
_println(");");
if (grammar instanceof LexerGrammar && (!saveText || atom.getAutoGenType() == GrammarElement.AUTO_GEN_BANG)) {
println("text.setLength(_saveIndex);"); // kill text atom put in buffer
}
}
protected void genMatchUsingAtomTokenType(GrammarAtom atom) {
// match() for trees needs the _t cursor
String astArgs = "";
if (grammar instanceof TreeWalkerGrammar) {
astArgs = "_t,";
}
// If the literal can be mangled, generate the symbolic constant instead
String mangledName = null;
String s = astArgs + getValueString(atom.getType());
// matching
println((atom.not ? "matchNot(" : "match(") + s + ");");
}
/** Generate the nextToken() rule. nextToken() is a synthetic
* lexer rule that is the implicit OR of all user-defined
* lexer rules.
*/
public void genNextToken() {
// Are there any public rules? If not, then just generate a
// fake nextToken().
boolean hasPublicRules = false;
for (int i = 0; i < grammar.rules.size(); i++) {
RuleSymbol rs = (RuleSymbol)grammar.rules.elementAt(i);
if (rs.isDefined() && rs.access.equals("public")) {
hasPublicRules = true;
break;
}
}
if (!hasPublicRules) {
println("");
println("public Token nextToken() throws TokenStreamException {");
println("\ttry {uponEOF();}");
println("\tcatch(CharStreamIOException csioe) {");
println("\t\tthrow new TokenStreamIOException(csioe.io);");
println("\t}");
println("\tcatch(CharStreamException cse) {");
println("\t\tthrow new TokenStreamException(cse.getMessage());");
println("\t}");
println("\treturn new CommonToken(Token.EOF_TYPE, \"\");");
println("}");
println("");
return;
}
// Create the synthesized nextToken() rule
RuleBlock nextTokenBlk = MakeGrammar.createNextTokenRule(grammar, grammar.rules, "nextToken");
// Define the nextToken rule symbol
RuleSymbol nextTokenRs = new RuleSymbol("mnextToken");
nextTokenRs.setDefined();
nextTokenRs.setBlock(nextTokenBlk);
nextTokenRs.access = "private";
grammar.define(nextTokenRs);
// Analyze the nextToken rule
boolean ok = grammar.theLLkAnalyzer.deterministic(nextTokenBlk);
// Generate the next token rule
String filterRule = null;
if (((LexerGrammar)grammar).filterMode) {
filterRule = ((LexerGrammar)grammar).filterRule;
}
println("");
println("public Token nextToken() throws TokenStreamException {");
tabs++;
println("Token theRetToken=null;");
_println("tryAgain:");
println("for (;;) {");
tabs++;
println("Token _token = null;");
println("int _ttype = Token.INVALID_TYPE;");
if (((LexerGrammar)grammar).filterMode) {
println("setCommitToPath(false);");
if (filterRule != null) {
// Here's a good place to ensure that the filter rule actually exists
if (!grammar.isDefined(CodeGenerator.encodeLexerRuleName(filterRule))) {
grammar.antlrTool.error("Filter rule " + filterRule + " does not exist in this lexer");
}
else {
RuleSymbol rs = (RuleSymbol)grammar.getSymbol(CodeGenerator.encodeLexerRuleName(filterRule));
if (!rs.isDefined()) {
grammar.antlrTool.error("Filter rule " + filterRule + " does not exist in this lexer");
}
else if (rs.access.equals("public")) {
grammar.antlrTool.error("Filter rule " + filterRule + " must be protected");
}
}
println("int _m;");
println("_m = mark();");
}
}
println("resetText();");
println("try { // for char stream error handling");
tabs++;
// Generate try around whole thing to trap scanner errors
println("try { // for lexical error handling");
tabs++;
// Test for public lexical rules with empty paths
for (int i = 0; i < nextTokenBlk.getAlternatives().size(); i++) {
Alternative a = nextTokenBlk.getAlternativeAt(i);
if (a.cache[1].containsEpsilon()) {
//String r = a.head.toString();
RuleRefElement rr = (RuleRefElement)a.head;
String r = CodeGenerator.decodeLexerRuleName(rr.targetRule);
antlrTool.warning("public lexical rule "+r+" is optional (can match \"nothing\")");
}
}
// Generate the block
String newline = System.getProperty("line.separator");
JavaBlockFinishingInfo howToFinish = genCommonBlock(nextTokenBlk, false);
String errFinish = "if (LA(1)==EOF_CHAR) {uponEOF(); _returnToken = makeToken(Token.EOF_TYPE);}";
errFinish += newline + "\t\t\t\t";
if (((LexerGrammar)grammar).filterMode) {
if (filterRule == null) {
errFinish += "else {consume(); continue tryAgain;}";
}
else {
errFinish += "else {" + newline +
"\t\t\t\t\tcommit();" + newline +
"\t\t\t\t\ttry {m" + filterRule + "(false);}" + newline +
"\t\t\t\t\tcatch(RecognitionException e) {" + newline +
"\t\t\t\t\t // catastrophic failure" + newline +
"\t\t\t\t\t reportError(e);" + newline +
"\t\t\t\t\t consume();" + newline +
"\t\t\t\t\t}" + newline +
"\t\t\t\t\tcontinue tryAgain;" + newline +
"\t\t\t\t}";
}
}
else {
errFinish += "else {" + throwNoViable + "}";
}
genBlockFinish(howToFinish, errFinish);
// at this point a valid token has been matched, undo "mark" that was done
if (((LexerGrammar)grammar).filterMode && filterRule != null) {
println("commit();");
}
// Generate literals test if desired
// make sure _ttype is set first; note _returnToken must be
// non-null as the rule was required to create it.
println("if ( _returnToken==null ) continue tryAgain; // found SKIP token");
println("_ttype = _returnToken.getType();");
if (((LexerGrammar)grammar).getTestLiterals()) {
genLiteralsTest();
}
// return token created by rule reference in switch
println("_returnToken.setType(_ttype);");
println("return _returnToken;");
// Close try block
tabs--;
println("}");
println("catch (RecognitionException e) {");
tabs++;
if (((LexerGrammar)grammar).filterMode) {
if (filterRule == null) {
println("if ( !getCommitToPath() ) {consume(); continue tryAgain;}");
}
else {
println("if ( !getCommitToPath() ) {");
tabs++;
println("rewind(_m);");
println("resetText();");
println("try {m" + filterRule + "(false);}");
println("catch(RecognitionException ee) {");
println(" // horrendous failure: error in filter rule");
println(" reportError(ee);");
println(" consume();");
println("}");
println("continue tryAgain;");
tabs--;
println("}");
}
}
if (nextTokenBlk.getDefaultErrorHandler()) {
println("reportError(e);");
println("consume();");
}
else {
// pass on to invoking routine
println("throw new TokenStreamRecognitionException(e);");
}
tabs--;
println("}");
// close CharStreamException try
tabs--;
println("}");
println("catch (CharStreamException cse) {");
println(" if ( cse instanceof CharStreamIOException ) {");
println(" throw new TokenStreamIOException(((CharStreamIOException)cse).io);");
println(" }");
println(" else {");
println(" throw new TokenStreamException(cse.getMessage());");
println(" }");
println("}");
// close for-loop
tabs--;
println("}");
// close method nextToken
tabs--;
println("}");
println("");
}
/** Gen a named rule block.
* ASTs are generated for each element of an alternative unless
* the rule or the alternative have a '!' modifier.
*
* If an alternative defeats the default tree construction, it
* must set <rule>_AST to the root of the returned AST.
*
* Each alternative that does automatic tree construction, builds
* up root and child list pointers in an ASTPair structure.
*
* A rule finishes by setting the returnAST variable from the
* ASTPair.
*
* @param rule The name of the rule to generate
* @param startSymbol true if the rule is a start symbol (i.e., not referenced elsewhere)
*/
public void genRule(RuleSymbol s, boolean startSymbol, int ruleNum) {
tabs = 1;
if (DEBUG_CODE_GENERATOR) System.out.println("genRule(" + s.getId() + ")");
if (!s.isDefined()) {
antlrTool.error("undefined rule: " + s.getId());
return;
}
// Generate rule return type, name, arguments
RuleBlock rblk = s.getBlock();
currentRule = rblk;
currentASTResult = s.getId();
// clear list of declared ast variables..
declaredASTVariables.clear();
// Save the AST generation state, and set it to that of the rule
boolean savegenAST = genAST;
genAST = genAST && rblk.getAutoGen();
// boolean oldsaveTest = saveText;
saveText = rblk.getAutoGen();
// print javadoc comment if any
if (s.comment != null) {
_println(s.comment);
}
// Gen method access and final qualifier
print(s.access + " final ");
// Gen method return type (note lexer return action set at rule creation)
if (rblk.returnAction != null) {
// Has specified return value
_print(extractTypeOfAction(rblk.returnAction, rblk.getLine(), rblk.getColumn()) + " ");
}
else {
// No specified return value
_print("void ");
}
// Gen method name
_print(s.getId() + "(");
// Additional rule parameters common to all rules for this grammar
_print(commonExtraParams);
if (commonExtraParams.length() != 0 && rblk.argAction != null) {
_print(",");
}
// Gen arguments
if (rblk.argAction != null) {
// Has specified arguments
_println("");
tabs++;
println(rblk.argAction);
tabs--;
print(")");
}
else {
// No specified arguments
_print(")");
}
// Gen throws clause and open curly
_print(" throws " + exceptionThrown);
if (grammar instanceof ParserGrammar) {
_print(", TokenStreamException");
}
else if (grammar instanceof LexerGrammar) {
_print(", CharStreamException, TokenStreamException");
}
// Add user-defined exceptions unless lexer (for now)
if (rblk.throwsSpec != null) {
if (grammar instanceof LexerGrammar) {
antlrTool.error("user-defined throws spec not allowed (yet) for lexer rule " + rblk.ruleName);
}
else {
_print(", " + rblk.throwsSpec);
}
}
_println(" {");
tabs++;
// Convert return action to variable declaration
if (rblk.returnAction != null)
println(rblk.returnAction + ";");
// print out definitions needed by rules for various grammar types
println(commonLocalVars);
if (grammar.traceRules) {
if (grammar instanceof TreeWalkerGrammar) {
println("traceIn(\"" + s.getId() + "\",_t);");
}
else {
println("traceIn(\"" + s.getId() + "\");");
}
}
if (grammar instanceof LexerGrammar) {
// lexer rule default return value is the rule's token name
// This is a horrible hack to support the built-in EOF lexer rule.
if (s.getId().equals("mEOF"))
println("_ttype = Token.EOF_TYPE;");
else
println("_ttype = " + s.getId().substring(1) + ";");
println("int _saveIndex;"); // used for element! (so we can kill text matched for element)
/*
println("boolean old_saveConsumedInput=saveConsumedInput;");
if ( !rblk.getAutoGen() ) { // turn off "save input" if ! on rule
println("saveConsumedInput=false;");
}
*/
}
// if debugging, write code to mark entry to the rule
if (grammar.debuggingOutput)
if (grammar instanceof ParserGrammar)
println("fireEnterRule(" + ruleNum + ",0);");
else if (grammar instanceof LexerGrammar)
println("fireEnterRule(" + ruleNum + ",_ttype);");
// Generate trace code if desired
if (grammar.debuggingOutput || grammar.traceRules) {
println("try { // debugging");
tabs++;
}
// Initialize AST variables
if (grammar instanceof TreeWalkerGrammar) {
// "Input" value for rule
println(labeledElementASTType + " " + s.getId() + "_AST_in = (" + labeledElementASTType + ")_t;");
}
if (grammar.buildAST) {
// Parser member used to pass AST returns from rule invocations
println("returnAST = null;");
// Tracks AST construction
// println("ASTPair currentAST = (inputState.guessing==0) ? new ASTPair() : null;");
println("ASTPair currentAST = new ASTPair();");
// User-settable return value for rule.
println(labeledElementASTType + " " + s.getId() + "_AST = null;");
}
genBlockPreamble(rblk);
genBlockInitAction(rblk);
println("");
// Search for an unlabeled exception specification attached to the rule
ExceptionSpec unlabeledUserSpec = rblk.findExceptionSpec("");
// Generate try block around the entire rule for error handling
if (unlabeledUserSpec != null || rblk.getDefaultErrorHandler()) {
println("try { // for error handling");
tabs++;
}
// Generate the alternatives
if (rblk.alternatives.size() == 1) {
// One alternative -- use simple form
Alternative alt = rblk.getAlternativeAt(0);
String pred = alt.semPred;
if (pred != null)
genSemPred(pred, currentRule.line);
if (alt.synPred != null) {
antlrTool.warning(
"Syntactic predicate ignored for single alternative",
grammar.getFilename(),
alt.synPred.getLine(),
alt.synPred.getColumn()
);
}
genAlt(alt, rblk);
}
else {
// Multiple alternatives -- generate complex form
boolean ok = grammar.theLLkAnalyzer.deterministic(rblk);
JavaBlockFinishingInfo howToFinish = genCommonBlock(rblk, false);
genBlockFinish(howToFinish, throwNoViable);
}
// Generate catch phrase for error handling
if (unlabeledUserSpec != null || rblk.getDefaultErrorHandler()) {
// Close the try block
tabs--;
println("}");
}
// Generate user-defined or default catch phrases
if (unlabeledUserSpec != null) {
genErrorHandler(unlabeledUserSpec);
}
else if (rblk.getDefaultErrorHandler()) {
// Generate default catch phrase
println("catch (" + exceptionThrown + " ex) {");
tabs++;
// Generate code to handle error if not guessing
if (grammar.hasSyntacticPredicate) {
println("if (inputState.guessing==0) {");
tabs++;
}
println("reportError(ex);");
if (!(grammar instanceof TreeWalkerGrammar)) {
// Generate code to consume until token in k==1 follow set
Lookahead follow = grammar.theLLkAnalyzer.FOLLOW(1, rblk.endNode);
String followSetName = getBitsetName(markBitsetForGen(follow.fset));
println("consume();");
println("consumeUntil(" + followSetName + ");");
}
else {
// Just consume one token
println("if (_t!=null) {_t = _t.getNextSibling();}");
}
if (grammar.hasSyntacticPredicate) {
tabs--;
// When guessing, rethrow exception
println("} else {");
println(" throw ex;");
println("}");
}
// Close catch phrase
tabs--;
println("}");
}
// Squirrel away the AST "return" value
if (grammar.buildAST) {
println("returnAST = " + s.getId() + "_AST;");
}
// Set return tree value for tree walkers
if (grammar instanceof TreeWalkerGrammar) {
println("_retTree = _t;");
}
// Generate literals test for lexer rules so marked
if (rblk.getTestLiterals()) {
if (s.access.equals("protected")) {
genLiteralsTestForPartialToken();
}
else {
genLiteralsTest();
}
}
// if doing a lexer rule, dump code to create token if necessary
if (grammar instanceof LexerGrammar) {
println("if ( _createToken && _token==null && _ttype!=Token.SKIP ) {");
println(" _token = makeToken(_ttype);");
println(" _token.setText(new String(text.getBuffer(), _begin, text.length()-_begin));");
println("}");
println("_returnToken = _token;");
}
// Gen the return statement if there is one (lexer has hard-wired return action)
if (rblk.returnAction != null) {
println("return " + extractIdOfAction(rblk.returnAction, rblk.getLine(), rblk.getColumn()) + ";");
}
if (grammar.debuggingOutput || grammar.traceRules) {
tabs--;
println("} finally { // debugging");
tabs++;
// If debugging, generate calls to mark exit of rule
if (grammar.debuggingOutput)
if (grammar instanceof ParserGrammar)
println("fireExitRule(" + ruleNum + ",0);");
else if (grammar instanceof LexerGrammar)
println("fireExitRule(" + ruleNum + ",_ttype);");
if (grammar.traceRules) {
if (grammar instanceof TreeWalkerGrammar) {
println("traceOut(\"" + s.getId() + "\",_t);");
}
else {
println("traceOut(\"" + s.getId() + "\");");
}
}
tabs--;
println("}");
}
tabs--;
println("}");
println("");
// Restore the AST generation state
genAST = savegenAST;
// restore char save state
// saveText = oldsaveTest;
}
private void GenRuleInvocation(RuleRefElement rr) {
// dump rule name
_print(rr.targetRule + "(");
// lexers must tell rule if it should set _returnToken
if (grammar instanceof LexerGrammar) {
// if labeled, could access Token, so tell rule to create
if (rr.getLabel() != null) {
_print("true");
}
else {
_print("false");
}
if (commonExtraArgs.length() != 0 || rr.args != null) {
_print(",");
}
}
// Extra arguments common to all rules for this grammar
_print(commonExtraArgs);
if (commonExtraArgs.length() != 0 && rr.args != null) {
_print(",");
}
// Process arguments to method, if any
RuleSymbol rs = (RuleSymbol)grammar.getSymbol(rr.targetRule);
if (rr.args != null) {
// When not guessing, execute user arg action
ActionTransInfo tInfo = new ActionTransInfo();
String args = processActionForSpecialSymbols(rr.args, 0, currentRule, tInfo);
if (tInfo.assignToRoot || tInfo.refRuleRoot != null) {
antlrTool.error("Arguments of rule reference '" + rr.targetRule + "' cannot set or ref #" +
currentRule.getRuleName(), grammar.getFilename(), rr.getLine(), rr.getColumn());
}
_print(args);
// Warn if the rule accepts no arguments
if (rs.block.argAction == null) {
antlrTool.warning("Rule '" + rr.targetRule + "' accepts no arguments", grammar.getFilename(), rr.getLine(), rr.getColumn());
}
}
else {
// For C++, no warning if rule has parameters, because there may be default
// values for all of the parameters
if (rs.block.argAction != null) {
antlrTool.warning("Missing parameters on reference to rule " + rr.targetRule, grammar.getFilename(), rr.getLine(), rr.getColumn());
}
}
_println(");");
// move down to the first child while parsing
if (grammar instanceof TreeWalkerGrammar) {
println("_t = _retTree;");
}
}
protected void genSemPred(String pred, int line) {
// translate $ and # references
ActionTransInfo tInfo = new ActionTransInfo();
pred = processActionForSpecialSymbols(pred, line, currentRule, tInfo);
// ignore translation info...we don't need to do anything with it.
String escapedPred = charFormatter.escapeString(pred);
// if debugging, wrap the semantic predicate evaluation in a method
// that can tell SemanticPredicateListeners the result
if (grammar.debuggingOutput && ((grammar instanceof ParserGrammar) || (grammar instanceof LexerGrammar)))
pred = "fireSemanticPredicateEvaluated(antlr.debug.SemanticPredicateEvent.VALIDATING,"
+ addSemPred(escapedPred) + "," + pred + ")";
println("if (!(" + pred + "))");
println(" throw new SemanticException(\"" + escapedPred + "\");");
}
/** Write an array of Strings which are the semantic predicate
* expressions. The debugger will reference them by number only
*/
protected void genSemPredMap() {
Enumeration e = semPreds.elements();
println("private String _semPredNames[] = {");
while (e.hasMoreElements())
println("\"" + e.nextElement() + "\",");
println("};");
}
protected void genSynPred(SynPredBlock blk, String lookaheadExpr) {
if (DEBUG_CODE_GENERATOR) System.out.println("gen=>(" + blk + ")");
// Dump synpred result variable
println("boolean synPredMatched" + blk.ID + " = false;");
// Gen normal lookahead test
println("if (" + lookaheadExpr + ") {");
tabs++;
// Save input state
if (grammar instanceof TreeWalkerGrammar) {
println("AST __t" + blk.ID + " = _t;");
}
else {
println("int _m" + blk.ID + " = mark();");
}
// Once inside the try, assume synpred works unless exception caught
println("synPredMatched" + blk.ID + " = true;");
println("inputState.guessing++;");
// if debugging, tell listeners that a synpred has started
if (grammar.debuggingOutput && ((grammar instanceof ParserGrammar) ||
(grammar instanceof LexerGrammar))) {
println("fireSyntacticPredicateStarted();");
}
syntacticPredLevel++;
println("try {");
tabs++;
gen((AlternativeBlock)blk); // gen code to test predicate
tabs--;
//println("System.out.println(\"pred "+blk+" succeeded\");");
println("}");
println("catch (" + exceptionThrown + " pe) {");
tabs++;
println("synPredMatched" + blk.ID + " = false;");
//println("System.out.println(\"pred "+blk+" failed\");");
tabs--;
println("}");
// Restore input state
if (grammar instanceof TreeWalkerGrammar) {
println("_t = __t" + blk.ID + ";");
}
else {
println("rewind(_m" + blk.ID + ");");
}
println("inputState.guessing--;");
// if debugging, tell listeners how the synpred turned out
if (grammar.debuggingOutput && ((grammar instanceof ParserGrammar) ||
(grammar instanceof LexerGrammar))) {
println("if (synPredMatched" + blk.ID + ")");
println(" fireSyntacticPredicateSucceeded();");
println("else");
println(" fireSyntacticPredicateFailed();");
}
syntacticPredLevel--;
tabs--;
// Close lookahead test
println("}");
// Test synred result
println("if ( synPredMatched" + blk.ID + " ) {");
}
/** Generate a static array containing the names of the tokens,
* indexed by the token type values. This static array is used
* to format error messages so that the token identifers or literal
* strings are displayed instead of the token numbers.
*
* If a lexical rule has a paraphrase, use it rather than the
* token label.
*/
public void genTokenStrings() {
// Generate a string for each token. This creates a static
// array of Strings indexed by token type.
println("");
println("public static final String[] _tokenNames = {");
tabs++;
// Walk the token vocabulary and generate a Vector of strings
// from the tokens.
Vector v = grammar.tokenManager.getVocabulary();
for (int i = 0; i < v.size(); i++) {
String s = (String)v.elementAt(i);
if (s == null) {
s = "<" + String.valueOf(i) + ">";
}
if (!s.startsWith("\"") && !s.startsWith("<")) {
TokenSymbol ts = (TokenSymbol)grammar.tokenManager.getTokenSymbol(s);
if (ts != null && ts.getParaphrase() != null) {
s = StringUtils.stripFrontBack(ts.getParaphrase(), "\"", "\"");
}
}
print(charFormatter.literalString(s));
if (i != v.size() - 1) {
_print(",");
}
_println("");
}
// Close the string array initailizer
tabs--;
println("};");
}
/** Create and set Integer token type objects that map
* to Java Class objects (which AST node to create).
*/
protected void genTokenASTNodeMap() {
println("");
println("protected void buildTokenTypeASTClassMap() {");
// Generate a map.put("T","TNode") for each token
// if heterogeneous node known for that token T.
tabs++;
boolean generatedNewHashtable = false;
int n = 0;
// Walk the token vocabulary and generate puts.
Vector v = grammar.tokenManager.getVocabulary();
for (int i = 0; i < v.size(); i++) {
String s = (String)v.elementAt(i);
if (s != null) {
TokenSymbol ts = grammar.tokenManager.getTokenSymbol(s);
if (ts != null && ts.getASTNodeType() != null) {
n++;
if ( !generatedNewHashtable ) {
// only generate if we are going to add a mapping
println("tokenTypeToASTClassMap = new Hashtable();");
generatedNewHashtable = true;
}
println("tokenTypeToASTClassMap.put(new Integer("+s+"), "+
ts.getASTNodeType()+".class);");
}
}
}
if ( n==0 ) {
println("tokenTypeToASTClassMap=null;");
}
tabs--;
println("};");
}
/** Generate the token types Java file */
protected void genTokenTypes(TokenManager tm) throws IOException {
// Open the token output Java file and set the currentOutput stream
// SAS: file open was moved to a method so a subclass can override
// This was mainly for the VAJ interface
setupOutput(tm.getName() + TokenTypesFileSuffix);
tabs = 0;
// Generate the header common to all Java files
genHeader();
// Do not use printAction because we assume tabs==0
println(behavior.getHeaderAction(""));
// Encapsulate the definitions in an interface. This can be done
// because they are all constants.
println("public interface " + tm.getName() + TokenTypesFileSuffix + " {");
tabs++;
// Generate a definition for each token type
Vector v = tm.getVocabulary();
// Do special tokens manually
println("int EOF = " + Token.EOF_TYPE + ";");
println("int NULL_TREE_LOOKAHEAD = " + Token.NULL_TREE_LOOKAHEAD + ";");
for (int i = Token.MIN_USER_TYPE; i < v.size(); i++) {
String s = (String)v.elementAt(i);
if (s != null) {
if (s.startsWith("\"")) {
// a string literal
StringLiteralSymbol sl = (StringLiteralSymbol)tm.getTokenSymbol(s);
if (sl == null) {
antlrTool.panic("String literal " + s + " not in symbol table");
}
else if (sl.label != null) {
println("int " + sl.label + " = " + i + ";");
}
else {
String mangledName = mangleLiteral(s);
if (mangledName != null) {
// We were able to create a meaningful mangled token name
println("int " + mangledName + " = " + i + ";");
// if no label specified, make the label equal to the mangled name
sl.label = mangledName;
}
else {
println("// " + s + " = " + i);
}
}
}
else if (!s.startsWith("<")) {
println("int " + s + " = " + i + ";");
}
}
}
// Close the interface
tabs--;
println("}");
// Close the tokens output file
currentOutput.close();
currentOutput = null;
exitIfError();
}
/** Get a string for an expression to generate creation of an AST subtree.
* @param v A Vector of String, where each element is an expression in the target language yielding an AST node.
*/
public String getASTCreateString(Vector v) {
if (v.size() == 0) {
return "";
}
StringBuffer buf = new StringBuffer();
buf.append("(" + labeledElementASTType +
")astFactory.make( (new ASTArray(" + v.size() +
"))");
for (int i = 0; i < v.size(); i++) {
buf.append(".add(" + v.elementAt(i) + ")");
}
buf.append(")");
return buf.toString();
}
/** Get a string for an expression to generate creating of an AST node
* @param atom The grammar node for which you are creating the node
* @param str The arguments to the AST constructor
*/
public String getASTCreateString(GrammarAtom atom, String astCtorArgs) {
//System.out.println("getASTCreateString("+atom+","+astCtorArgs+")");
if (atom != null && atom.getASTNodeType() != null) {
// they specified a type either on the reference or in tokens{} section
return "("+atom.getASTNodeType()+")"+
"astFactory.create("+astCtorArgs+",\""+atom.getASTNodeType()+"\")";
}
else {
// must be an action or something since not referencing an atom
return getASTCreateString(astCtorArgs);
}
}
/** Get a string for an expression to generate creating of an AST node.
* Parse the first (possibly only) argument looking for the token type.
* If the token type is a valid token symbol, ask for it's AST node type
* and add to the end if only 2 arguments. The forms are #[T], #[T,"t"],
* and as of 2.7.2 #[T,"t",ASTclassname].
*
* @param str The arguments to the AST constructor
*/
public String getASTCreateString(String astCtorArgs) {
//System.out.println("AST CTOR: "+astCtorArgs);
if ( astCtorArgs==null ) {
astCtorArgs = "";
}
int nCommas = 0;
for (int i=0; i<astCtorArgs.length(); i++) {
if ( astCtorArgs.charAt(i)==',' ) {
nCommas++;
}
}
//System.out.println("num commas="+nCommas);
if ( nCommas<2 ) { // if 1 or 2 args
int firstComma = astCtorArgs.indexOf(',');
int lastComma = astCtorArgs.lastIndexOf(',');
String tokenName = astCtorArgs;
if ( nCommas>0 ) {
tokenName = astCtorArgs.substring(0,firstComma);
}
//System.out.println("Checking for ast node type of "+tokenName);
TokenSymbol ts = grammar.tokenManager.getTokenSymbol(tokenName);
if ( ts!=null ) {
String astNodeType = ts.getASTNodeType();
//System.out.println("node type of "+tokenName+" is "+astNodeType);
String emptyText = "";
if ( nCommas==0 ) {
// need to add 2nd arg of blank text for token text
emptyText = ",\"\"";
}
if ( astNodeType!=null ) {
return "("+astNodeType+")"+
"astFactory.create("+astCtorArgs+emptyText+",\""+astNodeType+"\")";
}
// fall through and just do a regular create with cast on front
// if necessary (it differs from default "AST").
}
if ( labeledElementASTType.equals("AST") ) {
return "astFactory.create("+astCtorArgs+")";
}
return "("+labeledElementASTType+")"+
"astFactory.create("+astCtorArgs+")";
}
// create default type or (since 2.7.2) 3rd arg is classname
return "(" + labeledElementASTType + ")astFactory.create(" + astCtorArgs + ")";
}
protected String getLookaheadTestExpression(Lookahead[] look, int k) {
StringBuffer e = new StringBuffer(100);
boolean first = true;
e.append("(");
for (int i = 1; i <= k; i++) {
BitSet p = look[i].fset;
if (!first) {
e.append(") && (");
}
first = false;
// Syn preds can yield <end-of-syn-pred> (epsilon) lookahead.
// There is no way to predict what that token would be. Just
// allow anything instead.
if (look[i].containsEpsilon()) {
e.append("true");
}
else {
e.append(getLookaheadTestTerm(i, p));
}
}
e.append(")");
return e.toString();
}
/**Generate a lookahead test expression for an alternate. This
* will be a series of tests joined by '&&' and enclosed by '()',
* the number of such tests being determined by the depth of the lookahead.
*/
protected String getLookaheadTestExpression(Alternative alt, int maxDepth) {
int depth = alt.lookaheadDepth;
if (depth == GrammarAnalyzer.NONDETERMINISTIC) {
// if the decision is nondeterministic, do the best we can: LL(k)
// any predicates that are around will be generated later.
depth = grammar.maxk;
}
if (maxDepth == 0) {
// empty lookahead can result from alt with sem pred
// that can see end of token. E.g., A : {pred}? ('a')? ;
return "( true )";
}
return "(" + getLookaheadTestExpression(alt.cache, depth) + ")";
}
/**Generate a depth==1 lookahead test expression given the BitSet.
* This may be one of:
* 1) a series of 'x==X||' tests
* 2) a range test using >= && <= where possible,
* 3) a bitset membership test for complex comparisons
* @param k The lookahead level
* @param p The lookahead set for level k
*/
protected String getLookaheadTestTerm(int k, BitSet p) {
// Determine the name of the item to be compared
String ts = lookaheadString(k);
// Generate a range expression if possible
int[] elems = p.toArray();
if (elementsAreRange(elems)) {
return getRangeExpression(k, elems);
}
// Generate a bitset membership test if possible
StringBuffer e;
int degree = p.degree();
if (degree == 0) {
return "true";
}
if (degree >= bitsetTestThreshold) {
int bitsetIdx = markBitsetForGen(p);
return getBitsetName(bitsetIdx) + ".member(" + ts + ")";
}
// Otherwise, generate the long-winded series of "x==X||" tests
e = new StringBuffer();
for (int i = 0; i < elems.length; i++) {
// Get the compared-to item (token or character value)
String cs = getValueString(elems[i]);
// Generate the element comparison
if (i > 0) e.append("||");
e.append(ts);
e.append("==");
e.append(cs);
}
return e.toString();
}
/** Return an expression for testing a contiguous renage of elements
* @param k The lookahead level
* @param elems The elements representing the set, usually from BitSet.toArray().
* @return String containing test expression.
*/
public String getRangeExpression(int k, int[] elems) {
if (!elementsAreRange(elems)) {
antlrTool.panic("getRangeExpression called with non-range");
}
int begin = elems[0];
int end = elems[elems.length - 1];
return
"(" + lookaheadString(k) + " >= " + getValueString(begin) + " && " +
lookaheadString(k) + " <= " + getValueString(end) + ")";
}
/** getValueString: get a string representation of a token or char value
* @param value The token or char value
*/
private String getValueString(int value) {
String cs;
if (grammar instanceof LexerGrammar) {
cs = charFormatter.literalChar(value);
}
else {
TokenSymbol ts = grammar.tokenManager.getTokenSymbolAt(value);
if (ts == null) {
return "" + value; // return token type as string
// tool.panic("vocabulary for token type " + value + " is null");
}
String tId = ts.getId();
if (ts instanceof StringLiteralSymbol) {
// if string literal, use predefined label if any
// if no predefined, try to mangle into LITERAL_xxx.
// if can't mangle, use int value as last resort
StringLiteralSymbol sl = (StringLiteralSymbol)ts;
String label = sl.getLabel();
if (label != null) {
cs = label;
}
else {
cs = mangleLiteral(tId);
if (cs == null) {
cs = String.valueOf(value);
}
}
}
else {
cs = tId;
}
}
return cs;
}
/**Is the lookahead for this alt empty? */
protected boolean lookaheadIsEmpty(Alternative alt, int maxDepth) {
int depth = alt.lookaheadDepth;
if (depth == GrammarAnalyzer.NONDETERMINISTIC) {
depth = grammar.maxk;
}
for (int i = 1; i <= depth && i <= maxDepth; i++) {
BitSet p = alt.cache[i].fset;
if (p.degree() != 0) {
return false;
}
}
return true;
}
private String lookaheadString(int k) {
if (grammar instanceof TreeWalkerGrammar) {
return "_t.getType()";
}
return "LA(" + k + ")";
}
/** Mangle a string literal into a meaningful token name. This is
* only possible for literals that are all characters. The resulting
* mangled literal name is literalsPrefix with the text of the literal
* appended.
* @return A string representing the mangled literal, or null if not possible.
*/
private String mangleLiteral(String s) {
String mangled = antlrTool.literalsPrefix;
for (int i = 1; i < s.length() - 1; i++) {
if (!Character.isLetter(s.charAt(i)) &&
s.charAt(i) != '_') {
return null;
}
mangled += s.charAt(i);
}
if (antlrTool.upperCaseMangledLiterals) {
mangled = mangled.toUpperCase();
}
return mangled;
}
/** Map an identifier to it's corresponding tree-node variable.
* This is context-sensitive, depending on the rule and alternative
* being generated
* @param idParam The identifier name to map
* @return The mapped id (which may be the same as the input), or null if the mapping is invalid due to duplicates
*/
public String mapTreeId(String idParam, ActionTransInfo transInfo) {
// if not in an action of a rule, nothing to map.
if (currentRule == null) return idParam;
boolean in_var = false;
String id = idParam;
if (grammar instanceof TreeWalkerGrammar) {
if (!grammar.buildAST) {
in_var = true;
}
// If the id ends with "_in", then map it to the input variable
else if (id.length() > 3 && id.lastIndexOf("_in") == id.length() - 3) {
// Strip off the "_in"
id = id.substring(0, id.length() - 3);
in_var = true;
}
}
// Check the rule labels. If id is a label, then the output
// variable is label_AST, and the input variable is plain label.
for (int i = 0; i < currentRule.labeledElements.size(); i++) {
AlternativeElement elt = (AlternativeElement)currentRule.labeledElements.elementAt(i);
if (elt.getLabel().equals(id)) {
return in_var ? id : id + "_AST";
}
}
// Failing that, check the id-to-variable map for the alternative.
// If the id is in the map, then output variable is the name in the
// map, and input variable is name_in
String s = (String)treeVariableMap.get(id);
if (s != null) {
if (s == NONUNIQUE) {
// There is more than one element with this id
antlrTool.error("Ambiguous reference to AST element "+id+
" in rule "+currentRule.getRuleName());
return null;
}
else if (s.equals(currentRule.getRuleName())) {
// a recursive call to the enclosing rule is
// ambiguous with the rule itself.
antlrTool.error("Ambiguous reference to AST element "+id+
" in rule "+currentRule.getRuleName());
return null;
}
else {
return in_var ? s + "_in" : s;
}
}
// Failing that, check the rule name itself. Output variable
// is rule_AST; input variable is rule_AST_in (treeparsers).
if (id.equals(currentRule.getRuleName())) {
String r = in_var ? id + "_AST_in" : id + "_AST";
if (transInfo != null) {
if (!in_var) {
transInfo.refRuleRoot = r;
}
}
return r;
}
else {
// id does not map to anything -- return itself.
return id;
}
}
/** Given an element and the name of an associated AST variable,
* create a mapping between the element "name" and the variable name.
*/
private void mapTreeVariable(AlternativeElement e, String name) {
// For tree elements, defer to the root
if (e instanceof TreeElement) {
mapTreeVariable(((TreeElement)e).root, name);
return;
}
// Determine the name of the element, if any, for mapping purposes
String elName = null;
// Don't map labeled items
if (e.getLabel() == null) {
if (e instanceof TokenRefElement) {
// use the token id
elName = ((TokenRefElement)e).atomText;
}
else if (e instanceof RuleRefElement) {
// use the rule name
elName = ((RuleRefElement)e).targetRule;
}
}
// Add the element to the tree variable map if it has a name
if (elName != null) {
if (treeVariableMap.get(elName) != null) {
// Name is already in the map -- mark it as duplicate
treeVariableMap.remove(elName);
treeVariableMap.put(elName, NONUNIQUE);
}
else {
treeVariableMap.put(elName, name);
}
}
}
/** Lexically process $var and tree-specifiers in the action.
* This will replace #id and #(...) with the appropriate
* function calls and/or variables etc...
*/
protected String processActionForSpecialSymbols(String actionStr,
int line,
RuleBlock currentRule,
ActionTransInfo tInfo) {
if (actionStr == null || actionStr.length() == 0) return null;
// The action trans info tells us (at the moment) whether an
// assignment was done to the rule's tree root.
if (grammar == null)
return actionStr;
// see if we have anything to do...
if ((grammar.buildAST && actionStr.indexOf('#') != -1) ||
grammar instanceof TreeWalkerGrammar ||
((grammar instanceof LexerGrammar ||
grammar instanceof ParserGrammar)
&& actionStr.indexOf('$') != -1)) {
// Create a lexer to read an action and return the translated version
antlr.actions.java.ActionLexer lexer =
new antlr.actions.java.ActionLexer(actionStr,
currentRule,
this,
tInfo);
lexer.setLineOffset(line);
lexer.setFilename(grammar.getFilename());
lexer.setTool(antlrTool);
try {
lexer.mACTION(true);
actionStr = lexer.getTokenObject().getText();
// System.out.println("action translated: "+actionStr);
// System.out.println("trans info is "+tInfo);
}
catch (RecognitionException ex) {
lexer.reportError(ex);
return actionStr;
}
catch (TokenStreamException tex) {
antlrTool.panic("Error reading action:" + actionStr);
return actionStr;
}
catch (CharStreamException io) {
antlrTool.panic("Error reading action:" + actionStr);
return actionStr;
}
}
return actionStr;
}
private void setupGrammarParameters(Grammar g) {
if (g instanceof ParserGrammar) {
labeledElementASTType = "AST";
if (g.hasOption("ASTLabelType")) {
Token tsuffix = g.getOption("ASTLabelType");
if (tsuffix != null) {
String suffix = StringUtils.stripFrontBack(tsuffix.getText(), "\"", "\"");
if (suffix != null) {
labeledElementASTType = suffix;
}
}
}
labeledElementType = "Token ";
labeledElementInit = "null";
commonExtraArgs = "";
commonExtraParams = "";
commonLocalVars = "";
lt1Value = "LT(1)";
exceptionThrown = "RecognitionException";
throwNoViable = "throw new NoViableAltException(LT(1), getFilename());";
}
else if (g instanceof LexerGrammar) {
labeledElementType = "char ";
labeledElementInit = "'\\0'";
commonExtraArgs = "";
commonExtraParams = "boolean _createToken";
commonLocalVars = "int _ttype; Token _token=null; int _begin=text.length();";
lt1Value = "LA(1)";
exceptionThrown = "RecognitionException";
throwNoViable = "throw new NoViableAltForCharException((char)LA(1), getFilename(), getLine(), getColumn());";
}
else if (g instanceof TreeWalkerGrammar) {
labeledElementASTType = "AST";
labeledElementType = "AST";
if (g.hasOption("ASTLabelType")) {
Token tsuffix = g.getOption("ASTLabelType");
if (tsuffix != null) {
String suffix = StringUtils.stripFrontBack(tsuffix.getText(), "\"", "\"");
if (suffix != null) {
labeledElementASTType = suffix;
labeledElementType = suffix;
}
}
}
if (!g.hasOption("ASTLabelType")) {
g.setOption("ASTLabelType", new Token(ANTLRTokenTypes.STRING_LITERAL, "AST"));
}
labeledElementInit = "null";
commonExtraArgs = "_t";
commonExtraParams = "AST _t";
commonLocalVars = "";
lt1Value = "(" + labeledElementASTType + ")_t";
exceptionThrown = "RecognitionException";
throwNoViable = "throw new NoViableAltException(_t);";
}
else {
antlrTool.panic("Unknown grammar type");
}
}
/** This method exists so a subclass, namely VAJCodeGenerator,
* can open the file in its own evil way. JavaCodeGenerator
* simply opens a text file...
*/
public void setupOutput(String className) throws IOException {
currentOutput = antlrTool.openOutputFile(className + ".java");
}
}