/*******************************************************************************
* Copyright (c) 2000, 2011 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.jdt.internal.ui.text;
import org.eclipse.core.runtime.Assert;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jdt.core.JavaCore;
import org.eclipse.jdt.core.formatter.DefaultCodeFormatterConstants;
import org.eclipse.jdt.internal.corext.util.CodeFormatterUtil;
import org.eclipse.jdt.internal.ui.JavaPlugin;
/**
* Uses the {@link org.eclipse.jdt.internal.ui.text.JavaHeuristicScanner} to
* get the indentation level for a certain position in a document.
*
* <p>
* An instance holds some internal position in the document and is therefore
* not threadsafe.
* </p>
*
* @since 3.0
*/
public final class JavaIndenter {
/**
* The JDT Core preferences.
* @since 3.2
*/
private final class CorePrefs {
final boolean prefUseTabs;
final int prefTabSize;
final int prefIndentationSize;
final boolean prefArrayDimensionsDeepIndent;
final int prefArrayIndent;
final boolean prefArrayDeepIndent;
final boolean prefTernaryDeepAlign;
final int prefTernaryIndent;
final int prefCaseIndent;
final int prefCaseBlockIndent;
final int prefSimpleIndent;
final int prefBracketIndent;
final boolean prefMethodDeclDeepIndent;
final int prefMethodDeclIndent;
final boolean prefMethodCallDeepIndent;
final int prefMethodCallIndent;
final boolean prefParenthesisDeepIndent;
final int prefParenthesisIndent;
final int prefBlockIndent;
final int prefMethodBodyIndent;
final int prefTypeIndent;
final boolean prefIndentBracesForBlocks;
final boolean prefIndentBracesForArrays;
final boolean prefIndentBracesForMethods;
final boolean prefIndentBracesForTypes;
final int prefContinuationIndent;
final boolean prefHasGenerics;
final String prefTabChar;
private final IJavaProject fProject;
/**
* Returns <code>true</code> if the class is used outside the workbench,
* <code>false</code> in normal mode
*
* @return <code>true</code> if the plug-ins are not available
*/
private boolean isStandalone() {
return JavaCore.getPlugin() == null;
}
/**
* Returns the possibly project-specific core preference defined under <code>key</code>.
*
* @param key the key of the preference
* @return the value of the preference
* @since 3.1
*/
private String getCoreFormatterOption(String key) {
if (fProject == null)
return JavaCore.getOption(key);
return fProject.getOption(key, true);
}
CorePrefs(IJavaProject project) {
fProject= project;
if (isStandalone()) {
prefUseTabs= true;
prefTabSize= 4;
prefIndentationSize= 4;
prefArrayDimensionsDeepIndent= true;
prefContinuationIndent= 2;
prefBlockIndent= 1;
prefArrayIndent= prefContinuationIndent;
prefArrayDeepIndent= true;
prefTernaryDeepAlign= false;
prefTernaryIndent= prefContinuationIndent;
prefCaseIndent= 0;
prefCaseBlockIndent= prefBlockIndent;
prefIndentBracesForBlocks= false;
prefSimpleIndent= (prefIndentBracesForBlocks && prefBlockIndent == 0) ? 1 : prefBlockIndent;
prefBracketIndent= prefBlockIndent;
prefMethodDeclDeepIndent= true;
prefMethodDeclIndent= 1;
prefMethodCallDeepIndent= false;
prefMethodCallIndent= 1;
prefParenthesisDeepIndent= false;
prefParenthesisIndent= prefContinuationIndent;
prefMethodBodyIndent= 1;
prefTypeIndent= 1;
prefIndentBracesForArrays= false;
prefIndentBracesForMethods= false;
prefIndentBracesForTypes= false;
prefHasGenerics= false;
prefTabChar= JavaCore.TAB;
} else {
prefUseTabs= prefUseTabs();
prefTabSize= prefTabSize();
prefIndentationSize= prefIndentationSize();
prefArrayDimensionsDeepIndent= prefArrayDimensionsDeepIndent();
prefContinuationIndent= prefContinuationIndent();
prefBlockIndent= prefBlockIndent();
prefArrayIndent= prefArrayIndent();
prefArrayDeepIndent= prefArrayDeepIndent();
prefTernaryDeepAlign= prefTernaryDeepAlign();
prefTernaryIndent= prefTernaryIndent();
prefCaseIndent= prefCaseIndent();
prefCaseBlockIndent= prefCaseBlockIndent();
prefIndentBracesForBlocks= prefIndentBracesForBlocks();
prefSimpleIndent= prefSimpleIndent();
prefBracketIndent= prefBracketIndent();
prefMethodDeclDeepIndent= prefMethodDeclDeepIndent();
prefMethodDeclIndent= prefMethodDeclIndent();
prefMethodCallDeepIndent= prefMethodCallDeepIndent();
prefMethodCallIndent= prefMethodCallIndent();
prefParenthesisDeepIndent= prefParenthesisDeepIndent();
prefParenthesisIndent= prefParenthesisIndent();
prefMethodBodyIndent= prefMethodBodyIndent();
prefTypeIndent= prefTypeIndent();
prefIndentBracesForArrays= prefIndentBracesForArrays();
prefIndentBracesForMethods= prefIndentBracesForMethods();
prefIndentBracesForTypes= prefIndentBracesForTypes();
prefHasGenerics= hasGenerics();
prefTabChar= getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_TAB_CHAR);
}
}
private boolean prefUseTabs() {
return !JavaCore.SPACE.equals(getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_TAB_CHAR));
}
private int prefTabSize() {
return CodeFormatterUtil.getTabWidth(fProject);
}
private int prefIndentationSize() {
return CodeFormatterUtil.getIndentWidth(fProject);
}
private boolean prefArrayDimensionsDeepIndent() {
return true; // sensible default, no formatter setting
}
private int prefArrayIndent() {
String option= getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_ALIGNMENT_FOR_EXPRESSIONS_IN_ARRAY_INITIALIZER);
try {
if (DefaultCodeFormatterConstants.getIndentStyle(option) == DefaultCodeFormatterConstants.INDENT_BY_ONE)
return 1;
} catch (IllegalArgumentException e) {
// ignore and return default
}
return prefContinuationIndent(); // default
}
private boolean prefArrayDeepIndent() {
String option= getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_ALIGNMENT_FOR_EXPRESSIONS_IN_ARRAY_INITIALIZER);
try {
return DefaultCodeFormatterConstants.getIndentStyle(option) == DefaultCodeFormatterConstants.INDENT_ON_COLUMN;
} catch (IllegalArgumentException e) {
// ignore and return default
}
return true;
}
private boolean prefTernaryDeepAlign() {
String option= getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_ALIGNMENT_FOR_CONDITIONAL_EXPRESSION);
try {
return DefaultCodeFormatterConstants.getIndentStyle(option) == DefaultCodeFormatterConstants.INDENT_ON_COLUMN;
} catch (IllegalArgumentException e) {
// ignore and return default
}
return false;
}
private int prefTernaryIndent() {
String option= getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_ALIGNMENT_FOR_CONDITIONAL_EXPRESSION);
try {
if (DefaultCodeFormatterConstants.getIndentStyle(option) == DefaultCodeFormatterConstants.INDENT_BY_ONE)
return 1;
else
return prefContinuationIndent();
} catch (IllegalArgumentException e) {
// ignore and return default
}
return prefContinuationIndent();
}
private int prefCaseIndent() {
if (DefaultCodeFormatterConstants.TRUE.equals(getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_INDENT_SWITCHSTATEMENTS_COMPARE_TO_SWITCH)))
return prefBlockIndent();
else
return 0;
}
private int prefCaseBlockIndent() {
if (DefaultCodeFormatterConstants.TRUE.equals(getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_INDENT_SWITCHSTATEMENTS_COMPARE_TO_CASES)))
return prefBlockIndent();
else
return 0;
}
private int prefSimpleIndent() {
if (prefIndentBracesForBlocks() && prefBlockIndent() == 0)
return 1;
else return prefBlockIndent();
}
private int prefBracketIndent() {
return prefBlockIndent();
}
private boolean prefMethodDeclDeepIndent() {
String option= getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_ALIGNMENT_FOR_PARAMETERS_IN_METHOD_DECLARATION);
try {
return DefaultCodeFormatterConstants.getIndentStyle(option) == DefaultCodeFormatterConstants.INDENT_ON_COLUMN;
} catch (IllegalArgumentException e) {
// ignore and return default
}
return true;
}
private int prefMethodDeclIndent() {
String option= getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_ALIGNMENT_FOR_PARAMETERS_IN_METHOD_DECLARATION);
try {
if (DefaultCodeFormatterConstants.getIndentStyle(option) == DefaultCodeFormatterConstants.INDENT_BY_ONE)
return 1;
else
return prefContinuationIndent();
} catch (IllegalArgumentException e) {
// ignore and return default
}
return 1;
}
private boolean prefMethodCallDeepIndent() {
String option= getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_ALIGNMENT_FOR_ARGUMENTS_IN_METHOD_INVOCATION);
try {
return DefaultCodeFormatterConstants.getIndentStyle(option) == DefaultCodeFormatterConstants.INDENT_ON_COLUMN;
} catch (IllegalArgumentException e) {
// ignore and return default
}
return false; // sensible default
}
private int prefMethodCallIndent() {
String option= getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_ALIGNMENT_FOR_ARGUMENTS_IN_METHOD_INVOCATION);
try {
if (DefaultCodeFormatterConstants.getIndentStyle(option) == DefaultCodeFormatterConstants.INDENT_BY_ONE)
return 1;
else
return prefContinuationIndent();
} catch (IllegalArgumentException e) {
// ignore and return default
}
return 1; // sensible default
}
private boolean prefParenthesisDeepIndent() {
return false; // don't do parenthesis deep indentation (check rev. 1.60 for experimental code)
}
private int prefParenthesisIndent() {
return prefContinuationIndent();
}
private int prefBlockIndent() {
String option= getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_INDENT_STATEMENTS_COMPARE_TO_BLOCK);
if (DefaultCodeFormatterConstants.FALSE.equals(option))
return 0;
return 1; // sensible default
}
private int prefMethodBodyIndent() {
if (DefaultCodeFormatterConstants.FALSE.equals(getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_INDENT_STATEMENTS_COMPARE_TO_BODY)))
return 0;
return 1; // sensible default
}
private int prefTypeIndent() {
String option= getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_INDENT_BODY_DECLARATIONS_COMPARE_TO_TYPE_HEADER);
if (DefaultCodeFormatterConstants.FALSE.equals(option))
return 0;
return 1; // sensible default
}
private boolean prefIndentBracesForBlocks() {
return DefaultCodeFormatterConstants.NEXT_LINE_SHIFTED.equals(getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_BRACE_POSITION_FOR_BLOCK));
}
private boolean prefIndentBracesForArrays() {
return DefaultCodeFormatterConstants.NEXT_LINE_SHIFTED.equals(getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_BRACE_POSITION_FOR_ARRAY_INITIALIZER));
}
private boolean prefIndentBracesForMethods() {
return DefaultCodeFormatterConstants.NEXT_LINE_SHIFTED.equals(getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_BRACE_POSITION_FOR_METHOD_DECLARATION));
}
private boolean prefIndentBracesForTypes() {
return DefaultCodeFormatterConstants.NEXT_LINE_SHIFTED.equals(getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_BRACE_POSITION_FOR_TYPE_DECLARATION));
}
private int prefContinuationIndent() {
try {
return Integer.parseInt(getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_CONTINUATION_INDENTATION));
} catch (NumberFormatException e) {
// ignore and return default
}
return 2; // sensible default
}
private boolean hasGenerics() {
return JavaCore.VERSION_1_5.compareTo(getCoreFormatterOption(JavaCore.COMPILER_SOURCE)) <= 0;
}
}
/** The document being scanned. */
private final IDocument fDocument;
/** The indentation accumulated by <code>findReferencePosition</code>. */
private int fIndent;
/**
* The absolute (character-counted) indentation offset for special cases
* (method defs, array initializers)
*/
private int fAlign;
/** The stateful scanposition for the indentation methods. */
private int fPosition;
/** The previous position. */
private int fPreviousPos;
/** The most recent token. */
private int fToken;
/** The line of <code>fPosition</code>. */
private int fLine;
/**
* The scanner we will use to scan the document. It has to be installed
* on the same document as the one we get.
*/
private final JavaHeuristicScanner fScanner;
/**
* The JDT Core preferences.
* @since 3.2
*/
private final CorePrefs fPrefs;
/**
* Creates a new instance.
*
* @param document the document to scan
* @param scanner the {@link JavaHeuristicScanner} to be used for scanning
* the document. It must be installed on the same <code>IDocument</code>.
*/
public JavaIndenter(IDocument document, JavaHeuristicScanner scanner) {
this(document, scanner, null);
}
/**
* Creates a new instance.
*
* @param document the document to scan
* @param scanner the {@link JavaHeuristicScanner}to be used for scanning
* the document. It must be installed on the same
* <code>IDocument</code>.
* @param project the java project to get the formatter preferences from, or
* <code>null</code> to use the workspace settings
* @since 3.1
*/
public JavaIndenter(IDocument document, JavaHeuristicScanner scanner, IJavaProject project) {
Assert.isNotNull(document);
Assert.isNotNull(scanner);
fDocument= document;
fScanner= scanner;
fPrefs= new CorePrefs(project);
}
/**
* Computes the indentation at the reference point of <code>position</code>.
*
* @param offset the offset in the document
* @return a String which reflects the indentation at the line in which the
* reference position to <code>offset</code> resides, or <code>null</code>
* if it cannot be determined
*/
public StringBuffer getReferenceIndentation(int offset) {
return getReferenceIndentation(offset, false);
}
/**
* Computes the indentation at the reference point of <code>position</code>.
*
* @param offset the offset in the document
* @param assumeOpeningBrace <code>true</code> if an opening brace should be assumed
* @return a String which reflects the indentation at the line in which the
* reference position to <code>offset</code> resides, or <code>null</code>
* if it cannot be determined
*/
private StringBuffer getReferenceIndentation(int offset, boolean assumeOpeningBrace) {
int unit;
if (assumeOpeningBrace)
unit= findReferencePosition(offset, Symbols.TokenLBRACE);
else
unit= findReferencePosition(offset, peekChar(offset));
// if we were unable to find anything, return null
if (unit == JavaHeuristicScanner.NOT_FOUND)
return null;
return getLeadingWhitespace(unit);
}
/**
* Computes the indentation at <code>offset</code>.
*
* @param offset the offset in the document
* @return a String which reflects the correct indentation for the line in
* which offset resides, or <code>null</code> if it cannot be
* determined
*/
public StringBuffer computeIndentation(int offset) {
return computeIndentation(offset, false);
}
/**
* Computes the indentation at <code>offset</code>.
*
* @param offset the offset in the document
* @param assumeOpeningBrace <code>true</code> if an opening brace should be assumed
* @return a String which reflects the correct indentation for the line in
* which offset resides, or <code>null</code> if it cannot be
* determined
*/
public StringBuffer computeIndentation(int offset, boolean assumeOpeningBrace) {
StringBuffer reference= getReferenceIndentation(offset, assumeOpeningBrace);
// handle special alignment
if (fAlign != JavaHeuristicScanner.NOT_FOUND) {
try {
// a special case has been detected.
IRegion line= fDocument.getLineInformationOfOffset(fAlign);
int lineOffset= line.getOffset();
return createIndent(lineOffset, fAlign, false);
} catch (BadLocationException e) {
return null;
}
}
if (reference == null)
return null;
// add additional indent
return createReusingIndent(reference, fIndent);
}
/**
* Computes the length of a <code>CharacterSequence</code>, counting
* a tab character as the size until the next tab stop and every other
* character as one.
*
* @param indent the string to measure
* @return the visual length in characters
*/
private int computeVisualLength(CharSequence indent) {
final int tabSize= fPrefs.prefTabSize;
int length= 0;
for (int i= 0; i < indent.length(); i++) {
char ch= indent.charAt(i);
switch (ch) {
case '\t':
if (tabSize > 0) {
int reminder= length % tabSize;
length += tabSize - reminder;
}
break;
case ' ':
length++;
break;
}
}
return length;
}
/**
* Strips any characters off the end of <code>reference</code> that exceed
* <code>indentLength</code>.
*
* @param reference the string to measure
* @param indentLength the maximum visual indentation length
* @return the stripped <code>reference</code>
*/
private StringBuffer stripExceedingChars(StringBuffer reference, int indentLength) {
final int tabSize= fPrefs.prefTabSize;
int measured= 0;
int chars= reference.length();
int i= 0;
for (; measured < indentLength && i < chars; i++) {
char ch= reference.charAt(i);
switch (ch) {
case '\t':
if (tabSize > 0) {
int reminder= measured % tabSize;
measured += tabSize - reminder;
}
break;
case ' ':
measured++;
break;
}
}
int deleteFrom= measured > indentLength ? i - 1 : i;
return reference.delete(deleteFrom, chars);
}
/**
* Returns the indentation of the line at <code>offset</code> as a
* <code>StringBuffer</code>. If the offset is not valid, the empty string
* is returned.
*
* @param offset the offset in the document
* @return the indentation (leading whitespace) of the line in which
* <code>offset</code> is located
*/
private StringBuffer getLeadingWhitespace(int offset) {
StringBuffer indent= new StringBuffer();
try {
IRegion line= fDocument.getLineInformationOfOffset(offset);
int lineOffset= line.getOffset();
int nonWS= fScanner.findNonWhitespaceForwardInAnyPartition(lineOffset, lineOffset + line.getLength());
indent.append(fDocument.get(lineOffset, nonWS - lineOffset));
return indent;
} catch (BadLocationException e) {
return indent;
}
}
/**
* Creates an indentation string of the length indent - start, consisting of
* the content in <code>fDocument</code> in the range [start, indent),
* with every character replaced by a space except for tabs, which are kept
* as such.
* <p>
* If <code>convertSpaceRunsToTabs</code> is <code>true</code>, every
* run of the number of spaces that make up a tab are replaced by a tab
* character. If it is not set, no conversion takes place, but tabs in the
* original range are still copied verbatim.
* </p>
*
* @param start the start of the document region to copy the indent from
* @param indent the exclusive end of the document region to copy the indent
* from
* @param convertSpaceRunsToTabs whether to convert consecutive runs of
* spaces to tabs
* @return the indentation corresponding to the document content specified
* by <code>start</code> and <code>indent</code>
*/
private StringBuffer createIndent(int start, final int indent, final boolean convertSpaceRunsToTabs) {
final boolean convertTabs= fPrefs.prefUseTabs && convertSpaceRunsToTabs;
final int tabLen= fPrefs.prefTabSize;
final StringBuffer ret= new StringBuffer();
try {
int spaces= 0;
while (start < indent) {
char ch= fDocument.getChar(start);
if (ch == '\t') {
ret.append('\t');
spaces= 0;
} else if (convertTabs) {
spaces++;
if (spaces == tabLen) {
ret.append('\t');
spaces= 0;
}
} else {
ret.append(' ');
}
start++;
}
// remainder
while (spaces-- > 0)
ret.append(' ');
} catch (BadLocationException e) {
}
return ret;
}
/**
* Creates a string with a visual length of the given
* <code>indentationSize</code>.
*
* @param buffer the original indent to reuse if possible
* @param additional the additional indentation units to add or subtract to
* reference
* @return the modified <code>buffer</code> reflecting the indentation
* adapted to <code>additional</code>
*/
private StringBuffer createReusingIndent(StringBuffer buffer, int additional) {
int refLength= computeVisualLength(buffer);
int addLength= fPrefs.prefIndentationSize * additional; // may be < 0
int totalLength= Math.max(0, refLength + addLength);
// copy the reference indentation for the indent up to the last tab
// stop within the maxCopy area
int minLength= Math.min(totalLength, refLength);
int tabSize= fPrefs.prefTabSize;
int maxCopyLength= tabSize > 0 ? minLength - minLength % tabSize : minLength; // maximum indent to copy
stripExceedingChars(buffer, maxCopyLength);
// add additional indent
int missing= totalLength - maxCopyLength;
final int tabs, spaces;
if (JavaCore.SPACE.equals(fPrefs.prefTabChar)) {
tabs= 0;
spaces= missing;
} else if (JavaCore.TAB.equals(fPrefs.prefTabChar)) {
tabs= tabSize > 0 ? missing / tabSize : 0;
spaces= tabSize > 0 ? missing % tabSize : missing;
} else if (DefaultCodeFormatterConstants.MIXED.equals(fPrefs.prefTabChar)) {
tabs= tabSize > 0 ? missing / tabSize : 0;
spaces= tabSize > 0 ? missing % tabSize : missing;
} else {
Assert.isTrue(false);
return null;
}
for(int i= 0; i < tabs; i++)
buffer.append('\t');
for(int i= 0; i < spaces; i++)
buffer.append(' ');
return buffer;
}
/**
* Returns the reference position regarding to indentation for <code>offset</code>,
* or <code>NOT_FOUND</code>. This method calls
* {@link #findReferencePosition(int, int) findReferencePosition(offset, nextChar)} where
* <code>nextChar</code> is the next character after <code>offset</code>.
*
* @param offset the offset for which the reference is computed
* @return the reference statement relative to which <code>offset</code>
* should be indented, or {@link JavaHeuristicScanner#NOT_FOUND}
*/
public int findReferencePosition(int offset) {
return findReferencePosition(offset, peekChar(offset));
}
/**
* Peeks the next char in the document that comes after <code>offset</code>
* on the same line as <code>offset</code>.
*
* @param offset the offset into document
* @return the token symbol of the next element, or TokenEOF if there is none
*/
private int peekChar(int offset) {
if (offset < fDocument.getLength()) {
try {
IRegion line= fDocument.getLineInformationOfOffset(offset);
int lineOffset= line.getOffset();
int next= fScanner.nextToken(offset, lineOffset + line.getLength());
return next;
} catch (BadLocationException e) {
}
}
return Symbols.TokenEOF;
}
/**
* Returns the reference position regarding to indentation for <code>position</code>,
* or <code>NOT_FOUND</code>.
*
* <p>If <code>peekNextChar</code> is <code>true</code>, the next token after
* <code>offset</code> is read and taken into account when computing the
* indentation. Currently, if the next token is the first token on the line
* (i.e. only preceded by whitespace), the following tokens are specially
* handled:
* <ul>
* <li><code>switch</code> labels are indented relative to the switch block</li>
* <li>opening curly braces are aligned correctly with the introducing code</li>
* <li>closing curly braces are aligned properly with the introducing code of
* the matching opening brace</li>
* <li>closing parenthesis' are aligned with their opening peer</li>
* <li>the <code>else</code> keyword is aligned with its <code>if</code>, anything
* else is aligned normally (i.e. with the base of any introducing statements).</li>
* <li>if there is no token on the same line after <code>offset</code>, the indentation
* is the same as for an <code>else</code> keyword</li>
* </ul>
*
* @param offset the offset for which the reference is computed
* @param nextToken the next token to assume in the document
* @return the reference statement relative to which <code>offset</code>
* should be indented, or {@link JavaHeuristicScanner#NOT_FOUND}
*/
public int findReferencePosition(int offset, int nextToken) {
boolean danglingElse= false;
boolean unindent= false;
boolean indent= false;
boolean matchBrace= false;
boolean matchParen= false;
boolean matchCase= false;
boolean throwsClause= false;
// account for un-indentation characters already typed in, but after position
// if they are on a line by themselves, the indentation gets adjusted
// accordingly
//
// also account for a dangling else
if (offset < fDocument.getLength()) {
try {
IRegion line= fDocument.getLineInformationOfOffset(offset);
int lineOffset= line.getOffset();
int prevPos= Math.max(offset - 1, 0);
boolean isFirstTokenOnLine= fDocument.get(lineOffset, prevPos + 1 - lineOffset).trim().length() == 0;
int prevToken= fScanner.previousToken(prevPos, JavaHeuristicScanner.UNBOUND);
boolean bracelessBlockStart= fScanner.isBracelessBlockStart(prevPos, JavaHeuristicScanner.UNBOUND);
switch (nextToken) {
case Symbols.TokenELSE:
danglingElse= true;
break;
case Symbols.TokenCASE:
case Symbols.TokenDEFAULT:
if (isFirstTokenOnLine)
matchCase= true;
break;
case Symbols.TokenLBRACE: // for opening-brace-on-new-line style
if (bracelessBlockStart && !fPrefs.prefIndentBracesForBlocks)
unindent= true;
else if ((prevToken == Symbols.TokenCOLON || prevToken == Symbols.TokenEQUAL) && !fPrefs.prefIndentBracesForArrays)
unindent= true;
else if (!bracelessBlockStart && fPrefs.prefIndentBracesForMethods)
indent= true;
break;
case Symbols.TokenRBRACE: // closing braces get unindented
if (isFirstTokenOnLine)
matchBrace= true;
break;
case Symbols.TokenRPAREN:
if (isFirstTokenOnLine)
matchParen= true;
break;
case Symbols.TokenTHROWS:
throwsClause= true;
break;
case Symbols.TokenPLUS:
if (isStringContinuation(offset)) {
if (isSecondLineOfStringContinuation(offset)) {
fAlign= JavaHeuristicScanner.NOT_FOUND;
fIndent= fPrefs.prefContinuationIndent;
} else {
int previousLineOffset= fDocument.getLineOffset(fDocument.getLineOfOffset(offset) - 1);
fAlign= fScanner.findNonWhitespaceForwardInAnyPartition(previousLineOffset, JavaHeuristicScanner.UNBOUND);
}
return fPosition;
}
break;
}
} catch (BadLocationException e) {
}
} else {
// don't assume an else could come if we are at the end of file
danglingElse= false;
}
int ref= findReferencePosition(offset, danglingElse, matchBrace, matchParen, matchCase, throwsClause);
if (unindent)
fIndent--;
if (indent)
fIndent++;
return ref;
}
/**
* Tells whether the given string is a continuation expression.
*
* @param offset the offset for which the check is done
* @return <code>true</code> if the offset is part of a string continuation, <code>false</code>
* otherwise
* @since 3.7
*/
private boolean isStringContinuation(int offset) {
int nextNonWSCharPosition= fScanner.findNonWhitespaceBackwardInAnyPartition(offset - 1, JavaHeuristicScanner.UNBOUND);
try {
if (fDocument.getChar(nextNonWSCharPosition) == '"')
return true;
else
return false;
} catch (BadLocationException e) {
JavaPlugin.log(e);
return false;
}
}
/**
* Checks if extra indentation for second line of string continuation is required.
*
* @param offset the offset for which the check is done
* @return returns <code>true</code> if extra indentation for second line of string continuation
* is required
* @since 3.7
*/
private boolean isSecondLineOfStringContinuation(int offset) {
try {
int offsetLine= fDocument.getLineOfOffset(offset);
fPosition= offset;
while (true) {
nextToken();
switch (fToken) {
// scopes: skip them
case Symbols.TokenRPAREN:
case Symbols.TokenRBRACKET:
case Symbols.TokenRBRACE:
case Symbols.TokenGREATERTHAN:
skipScope();
break;
case Symbols.TokenPLUS:
if ((offsetLine - fLine) > 1) {
return false;
}
break;
case Symbols.TokenCOMMA:
case Symbols.TokenLPAREN:
case Symbols.TokenLBRACE:
case Symbols.TokenEQUAL:
int stringStartingOffset= fScanner.findNonWhitespaceForwardInAnyPartition(fPosition + 1, JavaHeuristicScanner.UNBOUND);
int stringStartingLine= fDocument.getLineOfOffset(stringStartingOffset);
if ((offsetLine - stringStartingLine) == 1) {
fPosition= stringStartingOffset;
return true;
} else {
return false;
}
case Symbols.TokenLBRACKET:
case Symbols.TokenEOF:
if ((offsetLine - fLine) == 1)
return true;
else
return false;
}
}
} catch (BadLocationException e) {
JavaPlugin.log(e);
return false;
}
}
/**
* Returns the reference position regarding to indentation for <code>position</code>, or
* <code>NOT_FOUND</code>.<code>fIndent</code> will contain the relative indentation (in
* indentation units, not characters) after the call. If there is a special alignment (e.g. for
* a method declaration where parameters should be aligned), <code>fAlign</code> will contain
* the absolute position of the alignment reference in <code>fDocument</code>, otherwise
* <code>fAlign</code> is set to <code>JavaHeuristicScanner.NOT_FOUND</code>. This method calls
* {@link #findReferencePosition(int, boolean, boolean, boolean, boolean, boolean)
* findReferencePosition(offset, danglingElse, matchBrace, matchParen, matchCase, throwsClause)}
* where <code>throwsClause</code> indicates whether a throws clause was found at
* <code>position</code>.
*
* @param offset the offset for which the reference is computed
* @param danglingElse whether a dangling else should be assumed at <code>position</code>
* @param matchBrace whether the position of the matching brace should be returned instead of
* doing code analysis
* @param matchParen whether the position of the matching parenthesis should be returned instead
* of doing code analysis
* @param matchCase whether the position of a switch statement reference should be returned
* (either an earlier case statement or the switch block brace)
* @return the reference statement relative to which <code>position</code> should be indented,
* or {@link JavaHeuristicScanner#NOT_FOUND}
*/
public int findReferencePosition(int offset, boolean danglingElse, boolean matchBrace, boolean matchParen, boolean matchCase) {
return findReferencePosition(offset, danglingElse, matchBrace, matchParen, matchCase, false);
}
/**
* Returns the reference position regarding to indentation for <code>position</code>, or
* <code>NOT_FOUND</code>.<code>fIndent</code> will contain the relative indentation (in
* indentation units, not characters) after the call. If there is a special alignment (e.g. for
* a method declaration where parameters should be aligned), <code>fAlign</code> will contain
* the absolute position of the alignment reference in <code>fDocument</code>, otherwise
* <code>fAlign</code> is set to <code>JavaHeuristicScanner.NOT_FOUND</code>.
*
* @param offset the offset for which the reference is computed
* @param danglingElse whether a dangling else should be assumed at <code>position</code>
* @param matchBrace whether the position of the matching brace should be returned instead of
* doing code analysis
* @param matchParen whether the position of the matching parenthesis should be returned instead
* of doing code analysis
* @param matchCase whether the position of a switch statement reference should be returned
* (either an earlier case statement or the switch block brace)
* @param throwsClause whether a throws clause was found at <code>position</code>
* @return the reference statement relative to which <code>position</code> should be indented,
* or {@link JavaHeuristicScanner#NOT_FOUND}
* @since 3.7
*/
public int findReferencePosition(int offset, boolean danglingElse, boolean matchBrace, boolean matchParen, boolean matchCase, boolean throwsClause) {
fIndent= 0; // the indentation modification
fAlign= JavaHeuristicScanner.NOT_FOUND;
fPosition= offset;
// forward cases
// an unindentation happens sometimes if the next token is special, namely on braces, parens and case labels
// align braces, but handle the case where we align with the method declaration start instead of
// the opening brace.
if (matchBrace) {
if (skipScope(Symbols.TokenLBRACE, Symbols.TokenRBRACE)) {
try {
// align with the opening brace that is on a line by its own
int lineOffset= fDocument.getLineOffset(fLine);
if (lineOffset <= fPosition && fDocument.get(lineOffset, fPosition - lineOffset).trim().length() == 0)
return fPosition;
} catch (BadLocationException e) {
// concurrent modification - walk default path
}
// if the opening brace is not on the start of the line, skip to the start
int pos= skipToStatementStart(true, true);
fIndent= 0; // indent is aligned with reference position
return pos;
} else {
// if we can't find the matching brace, the heuristic is to unindent
// by one against the normal position
int pos= findReferencePosition(offset, danglingElse, false, matchParen, matchCase, throwsClause);
fIndent--;
return pos;
}
}
// align parenthesis'
if (matchParen) {
if (skipScope(Symbols.TokenLPAREN, Symbols.TokenRPAREN)) {
fIndent= fPrefs.prefContinuationIndent;
return fPosition;
} else {
// if we can't find the matching paren, the heuristic is to unindent
// by one against the normal position
int pos= findReferencePosition(offset, danglingElse, matchBrace, false, matchCase, throwsClause);
fIndent--;
return pos;
}
}
// the only reliable way to get case labels aligned (due to many different styles of using braces in a block)
// is to go for another case statement, or the scope opening brace
if (matchCase) {
return matchCaseAlignment();
}
nextToken();
switch (fToken) {
case Symbols.TokenGREATERTHAN:
case Symbols.TokenRBRACE:
// skip the block and fall through
// if we can't complete the scope, reset the scan position
int pos= fPosition;
if (!skipScope())
fPosition= pos;
return skipToStatementStart(danglingElse, false);
case Symbols.TokenSEMICOLON:
// this is the 90% case: after a statement block
// the end of the previous statement / block previous.end
// search to the end of the statement / block before the previous; the token just after that is previous.start
pos= fPosition;
if (isSemicolonPartOfForStatement()) {
fIndent= fPrefs.prefContinuationIndent;
return fPosition;
} else {
fPosition= pos;
if (isTryWithResources()) {
fIndent= fPrefs.prefContinuationIndent;
return fPosition;
} else {
fPosition= pos;
return skipToStatementStart(danglingElse, false);
}
}
// scope introduction: special treat who special is
case Symbols.TokenLPAREN:
case Symbols.TokenLBRACE:
case Symbols.TokenLBRACKET:
return handleScopeIntroduction(offset + 1);
case Symbols.TokenEOF:
// trap when hitting start of document
return JavaHeuristicScanner.NOT_FOUND;
case Symbols.TokenEQUAL:
// indent assignments
return handleEqual();
case Symbols.TokenCOLON:
// TODO handle ternary deep indentation
fIndent= fPrefs.prefCaseBlockIndent;
return fPosition;
case Symbols.TokenQUESTIONMARK:
if (fPrefs.prefTernaryDeepAlign) {
setFirstElementAlignment(fPosition, offset + 1);
return fPosition;
} else {
fIndent= fPrefs.prefTernaryIndent;
return fPosition;
}
// indentation for blockless introducers:
case Symbols.TokenDO:
case Symbols.TokenWHILE:
case Symbols.TokenELSE:
fIndent= fPrefs.prefSimpleIndent;
return fPosition;
case Symbols.TokenTRY:
return skipToStatementStart(danglingElse, false);
case Symbols.TokenRBRACKET:
fIndent= fPrefs.prefContinuationIndent;
return fPosition;
case Symbols.TokenRPAREN:
if (throwsClause) {
fIndent= fPrefs.prefContinuationIndent;
return fPosition;
}
int line= fLine;
if (skipScope(Symbols.TokenLPAREN, Symbols.TokenRPAREN)) {
int scope= fPosition;
nextToken();
if (fToken == Symbols.TokenIF || fToken == Symbols.TokenWHILE || fToken == Symbols.TokenFOR) {
fIndent= fPrefs.prefSimpleIndent;
return fPosition;
}
fPosition= scope;
if (looksLikeMethodDecl()) {
return skipToStatementStart(danglingElse, false);
}
if (fToken == Symbols.TokenCATCH) {
return skipToStatementStart(danglingElse, false);
}
fPosition= scope;
if (looksLikeAnonymousTypeDecl()) {
return skipToStatementStart(danglingElse, false);
}
fPosition= scope;
if (looksLikeAnnotation()) {
return skipToStatementStart(danglingElse, false);
}
}
// restore
fPosition= offset;
fLine= line;
return skipToPreviousListItemOrListStart();
case Symbols.TokenRETURN:
fIndent= fPrefs.prefContinuationIndent;
return fPosition;
case Symbols.TokenPLUS:
if (isStringContinuation(fPosition)) {
try {
if (isSecondLineOfStringContinuation(offset)) {
fAlign= JavaHeuristicScanner.NOT_FOUND;
fIndent= fPrefs.prefContinuationIndent;
} else {
int previousLineOffset= fDocument.getLineOffset(fDocument.getLineOfOffset(offset) - 1);
fAlign= fScanner.findNonWhitespaceForwardInAnyPartition(previousLineOffset, JavaHeuristicScanner.UNBOUND);
}
} catch (BadLocationException e) {
JavaPlugin.log(e);
}
return fPosition;
}
fPosition= offset;
return skipToPreviousListItemOrListStart();
case Symbols.TokenCOMMA:
// inside a list of some type
// easy if there is already a list item before with its own indentation - we just align
// if not: take the start of the list ( LPAREN, LBRACE, LBRACKET ) and either align or
// indent by list-indent
default:
// inside whatever we don't know about: similar to the list case:
// if we are inside a continued expression, then either align with a previous line that has indentation
// or indent from the expression start line (either a scope introducer or the start of the expr).
return skipToPreviousListItemOrListStart();
}
}
/**
* Checks if the statement at position is itself a continuation of the previous, else sets the
* indentation to Continuation Indent.
*
* @return the position of the token
* @since 3.7
*/
private int handleEqual() {
try {
//If this line is itself continuation of the previous then do nothing
IRegion line= fDocument.getLineInformationOfOffset(fPosition);
int nonWS= fScanner.findNonWhitespaceBackward(line.getOffset(), JavaHeuristicScanner.UNBOUND);
if (nonWS != Symbols.TokenEOF) {
int tokenAtPreviousLine= fScanner.nextToken(nonWS, nonWS + 1);
if (tokenAtPreviousLine != Symbols.TokenSEMICOLON && tokenAtPreviousLine != Symbols.TokenRBRACE && tokenAtPreviousLine != Symbols.TokenLBRACE
&& tokenAtPreviousLine != Symbols.TokenEOF)
return fPosition;
}
} catch (BadLocationException e) {
return fPosition;
}
fIndent= fPrefs.prefContinuationIndent;
return fPosition;
}
/**
* Checks if the semicolon at the current position is part of a for statement.
*
* @return returns <code>true</code> if current position is part of for statement
* @since 3.7
*/
private boolean isSemicolonPartOfForStatement() {
int semiColonCount= 1;
while (true) {
nextToken();
switch (fToken) {
case Symbols.TokenFOR:
return true;
case Symbols.TokenLBRACE:
return false;
case Symbols.TokenSEMICOLON:
semiColonCount++;
if (semiColonCount > 2)
return false;
break;
case Symbols.TokenCOLON:
return false;
case Symbols.TokenEOF:
return false;
}
}
}
/**
* Checks if the semicolon at the current position is part of a try with resources statement.
*
* @return returns <code>true</code> if current position is part of try with resources statement
* @since 3.7
*/
private boolean isTryWithResources() {
while (true) {
nextToken();
switch (fToken) {
case Symbols.TokenTRY:
return true;
case Symbols.TokenLBRACE:
return false;
case Symbols.TokenEOF:
return false;
}
}
}
/**
* Skips to the start of a statement that ends at the current position.
*
* @param danglingElse whether to indent aligned with the last <code>if</code>
* @param isInBlock whether the current position is inside a block, which limits the search scope to the next scope introducer
* @return the reference offset of the start of the statement
*/
private int skipToStatementStart(boolean danglingElse, boolean isInBlock) {
final int NOTHING= 0;
final int READ_PARENS= 1;
final int READ_IDENT= 2;
int mayBeMethodBody= NOTHING;
boolean isTypeBody= false;
while (true) {
nextToken();
if (isInBlock) {
switch (fToken) {
// exit on all block introducers
case Symbols.TokenIF:
case Symbols.TokenELSE:
case Symbols.TokenCATCH:
case Symbols.TokenDO:
case Symbols.TokenWHILE:
case Symbols.TokenFINALLY:
case Symbols.TokenFOR:
case Symbols.TokenTRY:
return fPosition;
case Symbols.TokenSTATIC:
mayBeMethodBody= READ_IDENT; // treat static blocks like methods
break;
case Symbols.TokenSYNCHRONIZED:
// if inside a method declaration, use body indentation
// else use block indentation.
if (mayBeMethodBody != READ_IDENT)
return fPosition;
break;
case Symbols.TokenCLASS:
case Symbols.TokenINTERFACE:
case Symbols.TokenENUM:
isTypeBody= true;
break;
case Symbols.TokenSWITCH:
fIndent= fPrefs.prefCaseIndent;
return fPosition;
}
}
switch (fToken) {
// scope introduction through: LPAREN, LBRACE, LBRACKET
// search stop on SEMICOLON, RBRACE, COLON, EOF
// -> the next token is the start of the statement (i.e. previousPos when backward scanning)
case Symbols.TokenLPAREN:
case Symbols.TokenLBRACE:
case Symbols.TokenLBRACKET:
case Symbols.TokenSEMICOLON:
case Symbols.TokenEOF:
if (isInBlock)
fIndent= getBlockIndent(mayBeMethodBody == READ_IDENT, isTypeBody);
// else: fIndent set by previous calls
return fPreviousPos;
case Symbols.TokenCOLON:
int pos= fPreviousPos;
if (!isConditional())
return pos;
break;
case Symbols.TokenRBRACE:
// RBRACE is a little tricky: it can be the end of an array definition, but
// usually it is the end of a previous block
pos= fPreviousPos; // store state
if (skipScope() && looksLikeArrayInitializerIntro()) {
continue; // it's an array
} else {
if (isInBlock)
fIndent= getBlockIndent(mayBeMethodBody == READ_IDENT, isTypeBody);
return pos; // it's not - do as with all the above
}
// scopes: skip them
case Symbols.TokenRPAREN:
if (isInBlock)
mayBeMethodBody= READ_PARENS;
//$FALL-THROUGH$
case Symbols.TokenRBRACKET:
case Symbols.TokenGREATERTHAN:
pos= fPreviousPos;
if (skipScope())
break;
else
return pos;
// IF / ELSE: align the position after the conditional block with the if
// so we are ready for an else, except if danglingElse is false
// in order for this to work, we must skip an else to its if
case Symbols.TokenIF:
if (danglingElse)
return fPosition;
else
break;
case Symbols.TokenELSE:
// skip behind the next if, as we have that one covered
pos= fPosition;
if (skipNextIF())
break;
else
return pos;
case Symbols.TokenCATCH:
case Symbols.TokenFINALLY:
pos= fPosition;
if (skipNextTRY())
break;
else
return pos;
case Symbols.TokenDO:
// align the WHILE position with its do
return fPosition;
case Symbols.TokenWHILE:
// this one is tricky: while can be the start of a while loop
// or the end of a do - while
pos= fPosition;
if (hasMatchingDo()) {
// continue searching from the DO on
break;
} else {
// continue searching from the WHILE on
fPosition= pos;
break;
}
case Symbols.TokenIDENT:
if (mayBeMethodBody == READ_PARENS)
mayBeMethodBody= READ_IDENT;
break;
default:
// keep searching
}
}
}
private int getBlockIndent(boolean isMethodBody, boolean isTypeBody) {
if (isTypeBody)
return fPrefs.prefTypeIndent + (fPrefs.prefIndentBracesForTypes ? 1 : 0);
else if (isMethodBody)
return fPrefs.prefMethodBodyIndent + (fPrefs.prefIndentBracesForMethods ? 1 : 0);
else
return fIndent;
}
/**
* Returns true if the colon at the current position is part of a conditional
* (ternary) expression, false otherwise.
*
* @return true if the colon at the current position is part of a conditional
*/
private boolean isConditional() {
while (true) {
nextToken();
switch (fToken) {
// search for case labels, which consist of (possibly qualified) identifiers or numbers
case Symbols.TokenIDENT:
case Symbols.TokenOTHER: // dots for qualified constants
continue;
case Symbols.TokenCASE:
case Symbols.TokenDEFAULT:
return false;
default:
return true;
}
}
}
/**
* Returns as a reference any previous <code>switch</code> labels (<code>case</code>
* or <code>default</code>) or the offset of the brace that scopes the switch
* statement. Sets <code>fIndent</code> to <code>prefCaseIndent</code> upon
* a match.
*
* @return the reference offset for a <code>switch</code> label
*/
private int matchCaseAlignment() {
while (true) {
nextToken();
switch (fToken) {
// invalid cases: another case label or an LBRACE must come before a case
// -> bail out with the current position
case Symbols.TokenLPAREN:
case Symbols.TokenLBRACKET:
case Symbols.TokenEOF:
return fPosition;
case Symbols.TokenLBRACE:
// opening brace of switch statement
fIndent= fPrefs.prefCaseIndent;
return fPosition;
case Symbols.TokenCASE:
case Symbols.TokenDEFAULT:
// align with previous label
fIndent= 0;
return fPosition;
// scopes: skip them
case Symbols.TokenRPAREN:
case Symbols.TokenRBRACKET:
case Symbols.TokenRBRACE:
case Symbols.TokenGREATERTHAN:
skipScope();
break;
default:
// keep searching
continue;
}
}
}
/**
* Returns the reference position for a list element. The algorithm
* tries to match any previous indentation on the same list. If there is none,
* the reference position returned is determined depending on the type of list:
* The indentation will either match the list scope introducer (e.g. for
* method declarations), so called deep indents, or simply increase the
* indentation by a number of standard indents. See also {@link #handleScopeIntroduction(int)}.
*
* @return the reference position for a list item: either a previous list item
* that has its own indentation, or the list introduction start.
*/
private int skipToPreviousListItemOrListStart() {
int startLine= fLine;
int startPosition= fPosition;
while (true) {
nextToken();
// if any line item comes with its own indentation, adapt to it
if (fLine < startLine) {
try {
int lineOffset= fDocument.getLineOffset(startLine);
int bound= Math.min(fDocument.getLength(), startPosition + 1);
fAlign= fScanner.findNonWhitespaceForwardInAnyPartition(lineOffset, bound);
} catch (BadLocationException e) {
// ignore and return just the position
}
return startPosition;
}
switch (fToken) {
// scopes: skip them
case Symbols.TokenRPAREN:
case Symbols.TokenRBRACKET:
case Symbols.TokenRBRACE:
case Symbols.TokenGREATERTHAN:
skipScope();
break;
// scope introduction: special treat who special is
case Symbols.TokenLPAREN:
case Symbols.TokenLBRACE:
case Symbols.TokenLBRACKET:
return handleScopeIntroduction(startPosition + 1);
case Symbols.TokenSEMICOLON:
int savedPosition= fPosition;
if (isSemicolonPartOfForStatement())
fIndent= fPrefs.prefContinuationIndent;
else
fPosition= savedPosition;
return fPosition;
case Symbols.TokenQUESTIONMARK:
if (fPrefs.prefTernaryDeepAlign) {
setFirstElementAlignment(fPosition - 1, fPosition + 1);
return fPosition;
} else {
fIndent= fPrefs.prefTernaryIndent;
return fPosition;
}
case Symbols.TokenRETURN:
fIndent= fPrefs.prefContinuationIndent;
return fPosition;
case Symbols.TokenEQUAL:
return handleEqual();
case Symbols.TokenEOF:
return 0;
}
}
}
/**
* Skips a scope and positions the cursor (<code>fPosition</code>) on the
* token that opens the scope. Returns <code>true</code> if a matching peer
* could be found, <code>false</code> otherwise. The current token when calling
* must be one out of <code>Symbols.TokenRPAREN</code>, <code>Symbols.TokenRBRACE</code>,
* and <code>Symbols.TokenRBRACKET</code>.
*
* @return <code>true</code> if a matching peer was found, <code>false</code> otherwise
*/
private boolean skipScope() {
switch (fToken) {
case Symbols.TokenRPAREN:
return skipScope(Symbols.TokenLPAREN, Symbols.TokenRPAREN);
case Symbols.TokenRBRACKET:
return skipScope(Symbols.TokenLBRACKET, Symbols.TokenRBRACKET);
case Symbols.TokenRBRACE:
return skipScope(Symbols.TokenLBRACE, Symbols.TokenRBRACE);
case Symbols.TokenGREATERTHAN:
if (!fPrefs.prefHasGenerics)
return false;
int storedPosition= fPosition;
int storedToken= fToken;
nextToken();
switch (fToken) {
case Symbols.TokenIDENT:
boolean isGenericStarter;
try {
isGenericStarter= !JavaHeuristicScanner.isGenericStarter(getTokenContent());
} catch (BadLocationException e) {
return false;
}
if (isGenericStarter)
break;
//$FALL-THROUGH$
case Symbols.TokenQUESTIONMARK:
case Symbols.TokenGREATERTHAN:
if (skipScope(Symbols.TokenLESSTHAN, Symbols.TokenGREATERTHAN))
return true;
}
// <> are harder to detect - restore the position if we fail
fPosition= storedPosition;
fToken= storedToken;
return false;
default:
Assert.isTrue(false);
return false;
}
}
/**
* Returns the contents of the current token.
*
* @return the contents of the current token
* @throws BadLocationException if the indices are out of bounds
* @since 3.1
*/
private CharSequence getTokenContent() throws BadLocationException {
return new DocumentCharacterIterator(fDocument, fPosition, fPreviousPos);
}
/**
* Handles the introduction of a new scope. The current token must be one out
* of <code>Symbols.TokenLPAREN</code>, <code>Symbols.TokenLBRACE</code>,
* and <code>Symbols.TokenLBRACKET</code>. Returns as the reference position
* either the token introducing the scope or - if available - the first
* java token after that.
*
* <p>Depending on the type of scope introduction, the indentation will align
* (deep indenting) with the reference position (<code>fAlign</code> will be
* set to the reference position) or <code>fIndent</code> will be set to
* the number of indentation units.
* </p>
*
* @param bound the bound for the search for the first token after the scope
* introduction.
* @return the indent
*/
private int handleScopeIntroduction(int bound) {
switch (fToken) {
// scope introduction: special treat who special is
case Symbols.TokenLPAREN:
int pos= fPosition; // store
// special: method declaration deep indentation
if (looksLikeMethodDecl()) {
if (fPrefs.prefMethodDeclDeepIndent)
return setFirstElementAlignment(pos, bound);
else {
fIndent= fPrefs.prefMethodDeclIndent;
return pos;
}
} else {
fPosition= pos;
if (looksLikeMethodCall()) {
if (fPrefs.prefMethodCallDeepIndent)
return setFirstElementAlignment(pos, bound);
else {
fIndent= fPrefs.prefMethodCallIndent;
return pos;
}
} else if (fPrefs.prefParenthesisDeepIndent)
return setFirstElementAlignment(pos, bound);
}
// normal: return the parenthesis as reference
fIndent= fPrefs.prefParenthesisIndent;
return pos;
case Symbols.TokenLBRACE:
pos= fPosition; // store
// special: array initializer
if (looksLikeArrayInitializerIntro())
if (fPrefs.prefArrayDeepIndent)
return setFirstElementAlignment(pos, bound);
else
fIndent= fPrefs.prefArrayIndent;
else
fIndent= fPrefs.prefBlockIndent;
// normal: skip to the statement start before the scope introducer
// opening braces are often on differently ending indents than e.g. a method definition
if (looksLikeArrayInitializerIntro() && !fPrefs.prefIndentBracesForArrays
|| !fPrefs.prefIndentBracesForBlocks) {
fPosition= pos; // restore
return skipToStatementStart(true, true); // set to true to match the first if
} else {
return pos;
}
case Symbols.TokenLBRACKET:
pos= fPosition; // store
// special: method declaration deep indentation
if (fPrefs.prefArrayDimensionsDeepIndent) {
return setFirstElementAlignment(pos, bound);
}
// normal: return the bracket as reference
fIndent= fPrefs.prefBracketIndent;
return pos; // restore
default:
Assert.isTrue(false);
return -1; // dummy
}
}
/**
* Sets the deep indent offset (<code>fAlign</code>) to either the offset
* right after <code>scopeIntroducerOffset</code> or - if available - the
* first Java token after <code>scopeIntroducerOffset</code>, but before
* <code>bound</code>.
*
* @param scopeIntroducerOffset the offset of the scope introducer
* @param bound the bound for the search for another element
* @return the reference position
*/
private int setFirstElementAlignment(int scopeIntroducerOffset, int bound) {
int firstPossible= scopeIntroducerOffset + 1; // align with the first position after the scope intro
fAlign= fScanner.findNonWhitespaceForwardInAnyPartition(firstPossible, bound);
if (fAlign == JavaHeuristicScanner.NOT_FOUND)
fAlign= firstPossible;
return fAlign;
}
/**
* Returns <code>true</code> if the next token received after calling
* <code>nextToken</code> is either an equal sign or an array designator ('[]').
*
* @return <code>true</code> if the next elements look like the start of an array definition
*/
private boolean looksLikeArrayInitializerIntro() {
nextToken();
if (fToken == Symbols.TokenEQUAL || skipBrackets()) {
return true;
}
return false;
}
/**
* Skips over the next <code>if</code> keyword. The current token when calling
* this method must be an <code>else</code> keyword. Returns <code>true</code>
* if a matching <code>if</code> could be found, <code>false</code> otherwise.
* The cursor (<code>fPosition</code>) is set to the offset of the <code>if</code>
* token.
*
* @return <code>true</code> if a matching <code>if</code> token was found, <code>false</code> otherwise
*/
private boolean skipNextIF() {
Assert.isTrue(fToken == Symbols.TokenELSE);
while (true) {
nextToken();
switch (fToken) {
// scopes: skip them
case Symbols.TokenRPAREN:
case Symbols.TokenRBRACKET:
case Symbols.TokenRBRACE:
case Symbols.TokenGREATERTHAN:
skipScope();
break;
case Symbols.TokenIF:
// found it, return
return true;
case Symbols.TokenELSE:
// recursively skip else-if blocks
skipNextIF();
break;
// shortcut scope starts
case Symbols.TokenLPAREN:
case Symbols.TokenLBRACE:
case Symbols.TokenLBRACKET:
case Symbols.TokenEOF:
return false;
}
}
}
/**
* Skips over the next <code>try</code> keyword. The current token when calling this method must
* be a <code>catch</code> or <code>finally</code> keyword. Returns <code>true</code> if a
* matching <code>try</code> could be found, <code>false</code> otherwise. The cursor (
* <code>fPosition</code>) is set to the offset of the <code>try</code> token.
*
* @return <code>true</code> if a matching <code>try</code> token was found, <code>false</code>
* otherwise
* @since 3.7
*/
private boolean skipNextTRY() {
Assert.isTrue(fToken == Symbols.TokenCATCH || fToken == Symbols.TokenFINALLY);
while (true) {
nextToken();
switch (fToken) {
// scopes: skip them
case Symbols.TokenRPAREN:
case Symbols.TokenRBRACKET:
case Symbols.TokenRBRACE:
case Symbols.TokenGREATERTHAN:
skipScope();
break;
case Symbols.TokenTRY:
// found it
return true;
// shortcut scope starts
case Symbols.TokenLPAREN:
case Symbols.TokenLBRACE:
case Symbols.TokenLBRACKET:
case Symbols.TokenEOF:
return false;
}
}
}
/**
* while(condition); is ambiguous when parsed backwardly, as it is a valid
* statement by its own, so we have to check whether there is a matching
* do. A <code>do</code> can either be separated from the while by a
* block, or by a single statement, which limits our search distance.
*
* @return <code>true</code> if the <code>while</code> currently in
* <code>fToken</code> has a matching <code>do</code>.
*/
private boolean hasMatchingDo() {
Assert.isTrue(fToken == Symbols.TokenWHILE);
nextToken();
switch (fToken) {
case Symbols.TokenRBRACE:
skipScope();
//$FALL-THROUGH$
case Symbols.TokenSEMICOLON:
skipToStatementStart(false, false);
return fToken == Symbols.TokenDO;
}
return false;
}
/**
* Skips brackets if the current token is a RBRACKET. There can be nothing
* but whitespace in between, this is only to be used for <code>[]</code> elements.
*
* @return <code>true</code> if a <code>[]</code> could be scanned, the
* current token is left at the LBRACKET.
*/
private boolean skipBrackets() {
if (fToken == Symbols.TokenRBRACKET) {
nextToken();
if (fToken == Symbols.TokenLBRACKET) {
return true;
}
}
return false;
}
/**
* Reads the next token in backward direction from the heuristic scanner
* and sets the fields <code>fToken, fPreviousPosition</code> and <code>fPosition</code>
* accordingly.
*/
private void nextToken() {
nextToken(fPosition);
}
/**
* Reads the next token in backward direction of <code>start</code> from
* the heuristic scanner and sets the fields <code>fToken, fPreviousPosition</code>
* and <code>fPosition</code> accordingly.
*
* @param start the start offset from which to scan backwards
*/
private void nextToken(int start) {
fToken= fScanner.previousToken(start - 1, JavaHeuristicScanner.UNBOUND);
fPreviousPos= start;
fPosition= fScanner.getPosition() + 1;
try {
fLine= fDocument.getLineOfOffset(fPosition);
} catch (BadLocationException e) {
fLine= -1;
}
}
/**
* Returns <code>true</code> if the current tokens look like a method
* declaration header (i.e. only the return type and method name). The
* heuristic calls <code>nextToken</code> and expects an identifier
* (method name) and a type declaration (an identifier with optional
* brackets) which also covers the visibility modifier of constructors; it
* does not recognize package visible constructors.
*
* @return <code>true</code> if the current position looks like a method
* declaration header.
*/
private boolean looksLikeMethodDecl() {
/*
* TODO This heuristic does not recognize package private constructors
* since those do have neither type nor visibility keywords.
* One option would be to go over the parameter list, but that might
* be empty as well, or not typed in yet - hard to do without an AST...
*/
nextToken();
if (fToken == Symbols.TokenIDENT) { // method name
do nextToken();
while (skipBrackets()); // optional brackets for array valued return types
return fToken == Symbols.TokenIDENT; // return type name
}
return false;
}
/**
* Returns <code>true</code> if the current tokens look like an annotation (i.e. an annotation
* name (potentially qualified) preceded by an at-sign).
*
* @return <code>true</code> if the current position looks like an annotation.
* @since 3.7
*/
private boolean looksLikeAnnotation() {
nextToken();
if (fToken == Symbols.TokenIDENT) { // Annotation name
nextToken();
while (fToken == Symbols.TokenOTHER) { // dot of qualification
nextToken();
if (fToken != Symbols.TokenIDENT) // qualifying name
return false;
nextToken();
}
return fToken == Symbols.TokenAT;
}
return false;
}
/**
* Returns <code>true</code> if the current tokens look like an anonymous type declaration
* header (i.e. a type name (potentially qualified) and a new keyword). The heuristic calls
* <code>nextToken</code> and expects a possibly qualified identifier (type name) and a new
* keyword
*
* @return <code>true</code> if the current position looks like a anonymous type declaration
* header.
*/
private boolean looksLikeAnonymousTypeDecl() {
nextToken();
if (fToken == Symbols.TokenIDENT) { // type name
nextToken();
while (fToken == Symbols.TokenOTHER) { // dot of qualification
nextToken();
if (fToken != Symbols.TokenIDENT) // qualifying name
return false;
nextToken();
}
return fToken == Symbols.TokenNEW;
}
return false;
}
/**
* Returns <code>true</code> if the current tokens look like a method
* call header (i.e. an identifier as opposed to a keyword taking parenthesized
* parameters such as <code>if</code>).
* <p>The heuristic calls <code>nextToken</code> and expects an identifier
* (method name).
*
* @return <code>true</code> if the current position looks like a method call
* header.
*/
private boolean looksLikeMethodCall() {
// TODO [5.0] add awareness for constructor calls with generic types: new ArrayList<String>()
nextToken();
return fToken == Symbols.TokenIDENT; // method name
}
/**
* Scans tokens for the matching opening peer. The internal cursor
* (<code>fPosition</code>) is set to the offset of the opening peer if found.
*
* @param openToken the opening peer token
* @param closeToken the closing peer token
* @return <code>true</code> if a matching token was found, <code>false</code>
* otherwise
*/
private boolean skipScope(int openToken, int closeToken) {
int depth= 1;
while (true) {
nextToken();
if (fToken == closeToken) {
depth++;
} else if (fToken == openToken) {
depth--;
if (depth == 0)
return true;
} else if (fToken == Symbols.TokenEOF) {
return false;
}
}
}
}