/*
* Copyright 2006 JBoss Inc
*
* 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.rule.builder.dialect.java;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeSet;
import org.drools.base.accumulators.JavaAccumulatorFunctionExecutor;
import org.drools.compiler.DescrBuildError;
import org.drools.compiler.Dialect;
import org.drools.lang.descr.AccumulateDescr;
import org.drools.lang.descr.BaseDescr;
import org.drools.rule.Accumulate;
import org.drools.rule.Declaration;
import org.drools.rule.Pattern;
import org.drools.rule.RuleConditionElement;
import org.drools.rule.builder.AccumulateBuilder;
import org.drools.rule.builder.RuleBuildContext;
import org.drools.rule.builder.RuleConditionBuilder;
import org.drools.rule.builder.dialect.java.parser.JavaLocalDeclarationDescr;
import org.drools.runtime.rule.AccumulateFunction;
import org.drools.spi.Accumulator;
/**
* A builder for the java dialect accumulate version
*
* @author etirelli
*/
public class JavaAccumulateBuilder extends AbstractJavaRuleBuilder
implements
AccumulateBuilder {
public RuleConditionElement build(final RuleBuildContext context,
final BaseDescr descr) {
return build( context,
descr,
null );
}
@SuppressWarnings("unchecked")
public RuleConditionElement build(final RuleBuildContext context,
final BaseDescr descr,
final Pattern prefixPattern) {
final AccumulateDescr accumDescr = (AccumulateDescr) descr;
if ( !accumDescr.hasValidInput() ) {
return null;
}
final RuleConditionBuilder builder = (RuleConditionBuilder) context.getDialect().getBuilder( accumDescr.getInput().getClass() );
final RuleConditionElement source = builder.build( context,
accumDescr.getInput() );
if ( source == null ) {
return null;
}
Accumulate accumulate = null;
if ( accumDescr.isExternalFunction() ) {
// if it is an external function, build a method for it
AccumulateFunction function = context.getConfiguration().getAccumulateFunction( accumDescr.getFunctionIdentifier() );
if( function == null ) {
context.getErrors().add( new DescrBuildError( accumDescr,
context.getRuleDescr(),
null,
"Unknown accumulate function: '"+accumDescr.getFunctionIdentifier()+"' on rule '"+context.getRuleDescr().getName()+"'. All accumulate functions must be registered before building a resource." ) );
return null;
}
final JavaAnalysisResult analysis = (JavaAnalysisResult) context.getDialect().analyzeBlock( context,
accumDescr,
accumDescr.getExpression(),
new Map[]{context.getDeclarationResolver().getDeclarationClasses( context.getRule() ), context.getPackageBuilder().getGlobals()} );
final List[] usedIdentifiers = analysis.getBoundIdentifiers();
final List<Declaration> tupleDeclarations = new ArrayList<Declaration>();
for ( int i = 0, size = usedIdentifiers[0].size(); i < size; i++ ) {
tupleDeclarations.add( context.getDeclarationResolver().getDeclaration( context.getRule(),
(String) usedIdentifiers[0].get( i ) ) );
}
final Declaration[] previousDeclarations = tupleDeclarations.toArray( new Declaration[tupleDeclarations.size()] );
final String[] requiredGlobals = (String[]) usedIdentifiers[1].toArray( new String[usedIdentifiers[1].size()] );
final Declaration[] sourceDeclArr = (Declaration[]) source.getOuterDeclarations().values().toArray( new Declaration[0] );
final String className = "accumulateExpression" + context.getNextId();
final Map<String, Object> map = createVariableContext( className,
(String) accumDescr.getExpression(),
context,
previousDeclarations,
sourceDeclArr,
requiredGlobals );
map.put( "readLocalsFromTuple",
accumDescr.isMultiPattern() ? Boolean.TRUE : Boolean.FALSE );
JavaAccumulatorFunctionExecutor accumulator = new JavaAccumulatorFunctionExecutor( function );
accumulate = new Accumulate( source,
previousDeclarations,
sourceDeclArr,
new Accumulator[] { accumulator } );
generatTemplates( "returnValueMethod",
"returnValueInvoker",
context,
className,
map,
accumulator,
accumDescr );
} else {
// ELSE, if it is not an external function, build it using the regular java builder
final String className = "Accumulate" + context.getNextId();
accumDescr.setClassName( className );
Map<String, Class< ? >>[] available = new Map[]{context.getDeclarationResolver().getDeclarationClasses( context.getRule() ), context.getPackageBuilder().getGlobals()};
final JavaAnalysisResult initCodeAnalysis = (JavaAnalysisResult) context.getDialect().analyzeBlock( context,
accumDescr,
accumDescr.getInitCode(),
available );
final Dialect.AnalysisResult actionCodeAnalysis = context.getDialect().analyzeBlock( context,
accumDescr,
accumDescr.getActionCode(),
available );
final Dialect.AnalysisResult resultCodeAnalysis = context.getDialect().analyzeExpression( context,
accumDescr,
accumDescr.getResultCode(),
available );
final Set<String> requiredDeclarations = new HashSet<String>( initCodeAnalysis.getBoundIdentifiers()[0] );
requiredDeclarations.addAll( actionCodeAnalysis.getBoundIdentifiers()[0] );
requiredDeclarations.addAll( resultCodeAnalysis.getBoundIdentifiers()[0] );
final Set<String> requiredGlobals = new HashSet<String>( initCodeAnalysis.getBoundIdentifiers()[1] );
requiredGlobals.addAll( actionCodeAnalysis.getBoundIdentifiers()[1] );
requiredGlobals.addAll( resultCodeAnalysis.getBoundIdentifiers()[1] );
if ( accumDescr.getReverseCode() != null ) {
final Dialect.AnalysisResult reverseCodeAnalysis = context.getDialect().analyzeBlock( context,
accumDescr,
accumDescr.getActionCode(),
available );
requiredDeclarations.addAll( reverseCodeAnalysis.getBoundIdentifiers()[0] );
requiredGlobals.addAll( reverseCodeAnalysis.getBoundIdentifiers()[1] );
}
final Declaration[] declarations = new Declaration[requiredDeclarations.size()];
int i = 0;
for ( Iterator<String> it = requiredDeclarations.iterator(); it.hasNext(); i++ ) {
declarations[i] = context.getDeclarationResolver().getDeclaration( context.getRule(),
it.next() );
}
final Declaration[] sourceDeclArr = (Declaration[]) source.getOuterDeclarations().values().toArray( new Declaration[0] );
final String[] globals = requiredGlobals.toArray( new String[requiredGlobals.size()] );
final Map<String, Object> map = createVariableContext( className,
null,
context,
declarations,
null,
globals );
map.put( "className",
accumDescr.getClassName() );
map.put( "innerDeclarations",
sourceDeclArr );
map.put( "isMultiPattern",
accumDescr.isMultiPattern() ? Boolean.TRUE : Boolean.FALSE );
final String initCode = this.fixInitCode( initCodeAnalysis,
accumDescr.getInitCode() );
final String actionCode = accumDescr.getActionCode();
final String resultCode = accumDescr.getResultCode();
String[] attributesTypes = new String[initCodeAnalysis.getLocalVariablesMap().size()];
String[] attributes = new String[initCodeAnalysis.getLocalVariablesMap().size()];
int index = 0;
for ( Map.Entry<String, JavaLocalDeclarationDescr> entry : initCodeAnalysis.getLocalVariablesMap().entrySet() ) {
attributes[index] = entry.getKey();
attributesTypes[index] = entry.getValue().getType();
index++;
}
map.put( "attributes",
attributes );
map.put( "attributesTypes",
attributesTypes );
map.put( "initCode",
initCode );
map.put( "actionCode",
actionCode );
map.put( "resultCode",
resultCode );
if ( accumDescr.getReverseCode() == null ) {
map.put( "reverseCode",
"" );
map.put( "supportsReverse",
"false" );
} else {
map.put( "reverseCode",
accumDescr.getReverseCode() );
map.put( "supportsReverse",
"true" );
}
map.put( "hashCode",
new Integer( actionCode.hashCode() ) );
accumulate = new Accumulate( source,
declarations,
sourceDeclArr );
generatTemplates( "accumulateInnerClass",
"accumulateInvoker",
context,
className,
map,
accumulate,
accumDescr );
}
return accumulate;
}
@SuppressWarnings("unchecked")
protected String fixInitCode(JavaAnalysisResult analysis,
final String originalCode) {
TreeSet<JavaLocalDeclarationDescr> locals = new TreeSet<JavaLocalDeclarationDescr>( new Comparator<JavaLocalDeclarationDescr>() {
public int compare(JavaLocalDeclarationDescr o1,
JavaLocalDeclarationDescr o2) {
return o1.getStart() - o2.getStart();
}
} );
for ( Iterator it = analysis.getLocalVariablesMap().values().iterator(); it.hasNext(); ) {
locals.add( (JavaLocalDeclarationDescr) it.next() );
}
StringBuilder initCode = new StringBuilder();
int lastAdded = 0;
for ( Iterator it = locals.iterator(); it.hasNext(); ) {
JavaLocalDeclarationDescr d = (JavaLocalDeclarationDescr) it.next();
// adding chunk
initCode.append( originalCode.substring( lastAdded,
d.getStart() ) );
lastAdded = d.getEnd();
// adding variable initializations
for ( Iterator vars = d.getIdentifiers().iterator(); vars.hasNext(); ) {
JavaLocalDeclarationDescr.IdentifierDescr id = (JavaLocalDeclarationDescr.IdentifierDescr) vars.next();
initCode.append( originalCode.substring( id.getStart(),
id.getEnd() ) );
initCode.append( ";" );
lastAdded = id.getEnd();
while ( lastAdded < originalCode.length() && (Character.isWhitespace( originalCode.charAt( lastAdded ) ) || originalCode.charAt( lastAdded ) == ';') ) {
lastAdded++;
}
}
}
initCode.append( originalCode.substring( lastAdded ) );
return initCode.toString();
}
}