/*
* Copyright 2005 Red Hat, Inc. and/or its affiliates.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.drools.compiler.rule.builder.dialect.java;
import org.antlr.runtime.ANTLRStringStream;
import org.antlr.runtime.CharStream;
import org.antlr.runtime.CommonTokenStream;
import org.antlr.runtime.RecognitionException;
import org.antlr.runtime.TokenStream;
import org.drools.core.base.EvaluatorWrapper;
import org.drools.compiler.compiler.BoundIdentifiers;
import org.drools.compiler.rule.builder.dialect.java.parser.JavaLexer;
import org.drools.compiler.rule.builder.dialect.java.parser.JavaLocalDeclarationDescr;
import org.drools.compiler.rule.builder.dialect.java.parser.JavaParser;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
/**
* Expression analyzer.
*/
public class JavaExprAnalyzer {
// ------------------------------------------------------------
// Constructors
// ------------------------------------------------------------
/**
* Construct.
*/
public JavaExprAnalyzer() {
// intentionally left blank.
}
// ------------------------------------------------------------
// Instance methods
// ------------------------------------------------------------
/**
* Analyze an expression.
*
* @param expr
* The expression to analyze.
* @param availableIdentifiers
* Total set of declarations available.
*
* @return The <code>Set</code> of declarations used by the expression.
* @throws RecognitionException
* If an error occurs in the parser.
*/
@SuppressWarnings("unchecked")
public JavaAnalysisResult analyzeExpression(final String expr,
final BoundIdentifiers availableIdentifiers) throws RecognitionException {
final JavaParser parser = parse( expr );
parser.conditionalOrExpression();
JavaAnalysisResult result = new JavaAnalysisResult();
result.setAnalyzedExpr(expr);
result.setIdentifiers(new HashSet<String>( parser.getIdentifiers() ) );
return analyze( result,
availableIdentifiers );
}
@SuppressWarnings("unchecked")
public JavaAnalysisResult analyzeBlock(final String expr,
final BoundIdentifiers availableIdentifiers) throws RecognitionException {
final JavaParser parser = parse( "{" + expr + "}" );
parser.block();
JavaAnalysisResult result = new JavaAnalysisResult();
result.setAnalyzedExpr(expr);
result.setIdentifiers( new HashSet<String>( parser.getIdentifiers() ) );
result.setLocalVariables( new HashMap<String,JavaLocalDeclarationDescr>() );
if( parser.getRootBlockDescr().getInScopeLocalVars() != null ) {
for( JavaLocalDeclarationDescr descr : parser.getRootBlockDescr().getInScopeLocalVars() ) {
for (JavaLocalDeclarationDescr.IdentifierDescr ident : descr.getIdentifiers()) {
result.addLocalVariable(ident.getIdentifier(), descr);
}
}
}
result.setBlockDescrs( parser.getRootBlockDescr() );
return analyze( result,
availableIdentifiers );
}
private JavaParser parse(final String expr) {
final CharStream charStream = new ANTLRStringStream(expr);
final JavaLexer lexer = new JavaLexer( charStream );
final TokenStream tokenStream = new CommonTokenStream( lexer );
return new JavaParser( tokenStream );
}
/**
* Analyze an expression.
*
* @param availableIdentifiers
* Total set of declarations available.
* @param result
* The AST for the expression.
*
* @return The <code>Set</code> of declarations used by the expression.
*
* @throws RecognitionException
* If an error occurs in the parser.
*/
private JavaAnalysisResult analyze(JavaAnalysisResult result,
BoundIdentifiers availableIdentifiers) throws RecognitionException {
final Set<String> identifiers = result.getIdentifiers();
final Set<String> notBound = new HashSet<String>( identifiers );
Map<String, Class<?>> usedDecls = new HashMap<String, Class<?>>();
Map<String, Class<?>> usedGlobals = new HashMap<String, Class<?>>();
Map<String, EvaluatorWrapper> usedOperators = new HashMap<String, EvaluatorWrapper>();
for ( Entry<String, Class<?>> entry : availableIdentifiers.getDeclrClasses().entrySet() ) {
if ( identifiers.contains( entry.getKey() ) ) {
usedDecls.put( entry.getKey(), entry.getValue() );
notBound.remove( entry.getKey() );
}
}
for ( String identifier : identifiers ) {
Class<?> type = availableIdentifiers.resolveVarType( identifier );
if (type != null) {
usedGlobals.put( identifier, type );
notBound.remove( identifier );
}
}
for ( Map.Entry<String, EvaluatorWrapper> op : availableIdentifiers.getOperators().entrySet() ) {
if ( identifiers.contains( op.getKey() ) ) {
usedOperators.put( op.getKey(), op.getValue() );
notBound.remove( op.getKey() );
}
}
BoundIdentifiers boundIdentifiers = new BoundIdentifiers( usedDecls,
availableIdentifiers.getContext(),
usedOperators,
availableIdentifiers.getThisClass() );
boundIdentifiers.setGlobals( usedGlobals );
result.setBoundIdentifiers( boundIdentifiers );
result.setNotBoundedIdentifiers( notBound );
return result;
}
}