/*
* 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.compiler.rule.builder.dialect.java;
import org.drools.compiler.compiler.AnalysisResult;
import org.drools.compiler.compiler.BoundIdentifiers;
import org.drools.compiler.compiler.DescrBuildError;
import org.drools.compiler.lang.descr.AccumulateDescr;
import org.drools.compiler.lang.descr.AccumulateDescr.AccumulateFunctionCallDescr;
import org.drools.compiler.lang.descr.AndDescr;
import org.drools.compiler.lang.descr.BaseDescr;
import org.drools.compiler.rule.builder.AccumulateBuilder;
import org.drools.compiler.rule.builder.RuleBuildContext;
import org.drools.compiler.rule.builder.RuleConditionBuilder;
import org.drools.compiler.rule.builder.dialect.java.parser.JavaLocalDeclarationDescr;
import org.drools.compiler.rule.builder.util.PackageBuilderUtil;
import org.drools.core.base.accumulators.JavaAccumulatorFunctionExecutor;
import org.drools.core.base.extractors.ArrayElementReader;
import org.drools.core.base.extractors.SelfReferenceClassFieldReader;
import org.drools.core.reteoo.RuleTerminalNode;
import org.drools.core.rule.Accumulate;
import org.drools.core.rule.Declaration;
import org.drools.core.rule.MultiAccumulate;
import org.drools.core.rule.Pattern;
import org.drools.core.rule.RuleConditionElement;
import org.drools.core.rule.SingleAccumulate;
import org.drools.core.spi.Accumulator;
import org.drools.core.spi.DeclarationScopeResolver;
import org.drools.core.spi.InternalReadAccessor;
import org.kie.api.runtime.rule.AccumulateFunction;
import java.util.Arrays;
import java.util.Comparator;
import java.util.HashMap;
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 static org.drools.compiler.rule.builder.dialect.java.JavaRuleBuilderHelper.createVariableContext;
import static org.drools.compiler.rule.builder.dialect.java.JavaRuleBuilderHelper.generateTemplates;
/**
* A builder for the java dialect accumulate version
*/
public class JavaAccumulateBuilder
implements
AccumulateBuilder {
public RuleConditionElement build( final RuleBuildContext context,
final BaseDescr descr ) {
return build( context,
descr,
null );
}
public RuleConditionElement build( final RuleBuildContext context,
final BaseDescr descr,
final Pattern prefixPattern ) {
final AccumulateDescr accumDescr = (AccumulateDescr) descr;
if ( !accumDescr.hasValidInput() ) {
return null;
}
// build source
BaseDescr input = accumDescr.getInput();
if( input instanceof AndDescr && ((AndDescr) input).getDescrs().size() == 1 ) {
input = ((AndDescr) input).getDescrs().get( 0 );
}
final RuleConditionBuilder builder = (RuleConditionBuilder) context.getDialect().getBuilder( input.getClass() );
final RuleConditionElement source = builder.build( context,
input );
if ( source == null ) {
return null;
}
final boolean readLocalsFromTuple = PackageBuilderUtil.isReadLocalsFromTuple(accumDescr, source);
Map<String, Declaration> declsInScope = context.getDeclarationResolver().getDeclarations( context.getRule() );
Map<String, Class< ? >> declCls = DeclarationScopeResolver.getDeclarationClasses( declsInScope );
Accumulate accumulate;
if ( accumDescr.isExternalFunction() ) {
// if it uses 1+ external function, build methods for them
accumulate = buildExternalFunctionCall( context,
accumDescr,
source,
declsInScope,
declCls,
readLocalsFromTuple );
} else {
// if it uses inline code, build the class for it
accumulate = buildInlineAccumulate( context,
accumDescr,
source,
declsInScope,
declCls,
readLocalsFromTuple );
}
return accumulate;
}
private Accumulate buildExternalFunctionCall( final RuleBuildContext context,
final AccumulateDescr accumDescr,
final RuleConditionElement source,
Map<String, Declaration> declsInScope,
Map<String, Class< ? >> declCls,
final boolean readLocalsFromTuple) {
// list of functions to build
final List<AccumulateFunctionCallDescr> funcCalls = accumDescr.getFunctions();
// list of available source declarations
final Declaration[] sourceDeclArr = source.getOuterDeclarations().values().toArray( new Declaration[0] );
Arrays.sort( sourceDeclArr, RuleTerminalNode.SortDeclarations.instance );
// the accumulator array
Accumulator[] accumulators = new Accumulator[funcCalls.size()];
// set of required previous declarations
Set<Declaration> requiredDecl = new HashSet<Declaration>();
// creating the custom array reader
InternalReadAccessor arrayReader = new SelfReferenceClassFieldReader( Object[].class,
"this" );
int index = 0;
Pattern pattern = (Pattern) context.getBuildStack().peek();
for ( AccumulateFunctionCallDescr fc : funcCalls ) {
// find the corresponding function
AccumulateFunction function = context.getConfiguration().getAccumulateFunction( fc.getFunction() );
if( function == null ) {
// might have been imported in the package
function = context.getKnowledgeBuilder().getPackage().getAccumulateFunctions().get(fc.getFunction());
}
if ( function == null ) {
context.addError( new DescrBuildError( accumDescr,
context.getRuleDescr(),
null,
"Unknown accumulate function: '" + fc.getFunction() + "' on rule '" + context.getRuleDescr().getName() + "'. All accumulate functions must be registered before building a resource." ) );
return null;
}
// if there is a binding, create the binding
if ( fc.getBind() != null ) {
if ( pattern.getDeclaration( fc.getBind() ) != null ) {
context.addError(new DescrBuildError(context.getParentDescr(),
accumDescr,
null,
"Duplicate declaration for variable '" + fc.getBind() + "' in the rule '" + context.getRule().getName() + "'"));
} else {
createResultBind( pattern,
index,
arrayReader,
fc,
function );
}
}
// analyze the expression
final JavaAnalysisResult analysis = (JavaAnalysisResult) context.getDialect().analyzeBlock( context,
accumDescr,
fc.getParams().length > 0 ? fc.getParams()[0] : "\"\"",
new BoundIdentifiers( declCls,
context.getKnowledgeBuilder().getGlobals() ) );
final BoundIdentifiers usedIdentifiers = analysis.getBoundIdentifiers();
// create the array of used declarations
final Declaration[] previousDeclarations = collectRequiredDeclarations( declsInScope,
requiredDecl,
usedIdentifiers );
// generate the code template
accumulators[index++] = generateFunctionCallCodeTemplate( context,
accumDescr,
sourceDeclArr,
fc,
function,
usedIdentifiers,
previousDeclarations,
readLocalsFromTuple );
}
if (accumDescr.isMultiFunction()) {
return new MultiAccumulate( source,
requiredDecl.toArray(new Declaration[requiredDecl.size()]),
accumulators );
} else {
return new SingleAccumulate( source,
requiredDecl.toArray(new Declaration[requiredDecl.size()]),
accumulators[0] );
}
}
private Declaration[] collectRequiredDeclarations( Map<String, Declaration> declsInScope,
Set<Declaration> requiredDecl,
final BoundIdentifiers usedIdentifiers ) {
final Declaration[] previousDeclarations = new Declaration[usedIdentifiers.getDeclrClasses().size()];
int i = 0;
for ( String key : usedIdentifiers.getDeclrClasses().keySet() ) {
Declaration d = declsInScope.get( key );
previousDeclarations[i++] = d;
requiredDecl.add( d );
}
return previousDeclarations;
}
private JavaAccumulatorFunctionExecutor generateFunctionCallCodeTemplate( final RuleBuildContext context,
final AccumulateDescr accumDescr,
final Declaration[] sourceDeclArr,
AccumulateFunctionCallDescr fc,
AccumulateFunction function,
final BoundIdentifiers usedIdentifiers,
final Declaration[] previousDeclarations,
final boolean readLocalsFromTuple ) {
final String className = "accumulateExpression" + context.getNextId();
final Map<String, Object> map = createVariableContext( className,
fc.getParams().length > 0 ? fc.getParams()[0] : "\"\"",
context,
previousDeclarations,
sourceDeclArr,
usedIdentifiers.getGlobals()
);
map.put( "readLocalsFromTuple",
readLocalsFromTuple ? Boolean.TRUE : Boolean.FALSE );
JavaAccumulatorFunctionExecutor accumulator = new JavaAccumulatorFunctionExecutor( function );
generateTemplates("returnValueMethod",
"returnValueInvoker",
context,
className,
map,
accumulator,
accumDescr);
return accumulator;
}
private void createResultBind( final Pattern pattern,
int index,
InternalReadAccessor arrayReader,
AccumulateFunctionCallDescr fc,
AccumulateFunction function ) {
// bind function result on the result pattern
Declaration declr = pattern.addDeclaration( fc.getBind() );
Class< ? > type = function.getResultType();
// this bit is different, notice its the ArrayElementReader that we wire up to, not the declaration.
ArrayElementReader reader = new ArrayElementReader( arrayReader,
index,
type );
declr.setReadAccessor( reader );
}
private Accumulate buildInlineAccumulate( final RuleBuildContext context,
final AccumulateDescr accumDescr,
final RuleConditionElement source,
Map<String, Declaration> decls,
Map<String, Class< ? >> declCls,
final boolean readLocalsFromTuple) {
// ELSE, if it is not an external function, build it using the regular java builder
final String className = "Accumulate" + context.getNextId();
accumDescr.setClassName( className );
BoundIdentifiers available = new BoundIdentifiers( declCls,
context.getKnowledgeBuilder().getGlobals() );
final JavaAnalysisResult initCodeAnalysis = (JavaAnalysisResult) context.getDialect().analyzeBlock( context,
accumDescr,
accumDescr.getInitCode(),
available );
final AnalysisResult actionCodeAnalysis = context.getDialect().analyzeBlock( context,
accumDescr,
accumDescr.getActionCode(),
available );
final AnalysisResult resultCodeAnalysis = context.getDialect().analyzeExpression( context,
accumDescr,
accumDescr.getResultCode(),
available );
final Set<String> requiredDeclarations = new HashSet<String>( initCodeAnalysis.getBoundIdentifiers().getDeclrClasses().keySet() );
requiredDeclarations.addAll( actionCodeAnalysis.getBoundIdentifiers().getDeclrClasses().keySet() );
requiredDeclarations.addAll( resultCodeAnalysis.getBoundIdentifiers().getDeclrClasses().keySet() );
final Map<String, Class< ? >> requiredGlobals = new HashMap<String, Class< ? >>( initCodeAnalysis.getBoundIdentifiers().getGlobals() );
requiredGlobals.putAll( actionCodeAnalysis.getBoundIdentifiers().getGlobals() );
requiredGlobals.putAll( resultCodeAnalysis.getBoundIdentifiers().getGlobals() );
if ( accumDescr.getReverseCode() != null ) {
final AnalysisResult reverseCodeAnalysis = context.getDialect().analyzeBlock( context,
accumDescr,
accumDescr.getActionCode(),
available );
requiredDeclarations.addAll( reverseCodeAnalysis.getBoundIdentifiers().getDeclrClasses().keySet() );
requiredGlobals.putAll( reverseCodeAnalysis.getBoundIdentifiers().getGlobals() );
}
final Declaration[] declarations = new Declaration[requiredDeclarations.size()];
int i = 0;
for ( Iterator<String> it = requiredDeclarations.iterator(); it.hasNext(); i++ ) {
declarations[i] = decls.get( it.next() );
}
final Declaration[] sourceDeclArr = source.getOuterDeclarations().values().toArray( new Declaration[0] );
Arrays.sort( sourceDeclArr, RuleTerminalNode.SortDeclarations.instance );
final Map<String, Object> map = createVariableContext( className,
null,
context,
declarations,
null,
requiredGlobals
);
map.put( "className",
accumDescr.getClassName() );
map.put( "innerDeclarations",
sourceDeclArr );
map.put( "isMultiPattern",
readLocalsFromTuple ? 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",
actionCode.hashCode());
SingleAccumulate accumulate = new SingleAccumulate(source, declarations);
generateTemplates("accumulateInnerClass",
"accumulateInvoker",
context,
className,
map,
accumulate.new Wirer(),
accumDescr);
return accumulate;
}
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 ( JavaLocalDeclarationDescr local : analysis.getLocalVariablesMap().values() ) {
locals.add( local );
}
StringBuilder initCode = new StringBuilder();
int lastAdded = 0;
for ( JavaLocalDeclarationDescr d : locals ) {
// adding chunk
initCode.append( originalCode.substring( lastAdded,
d.getStart() ) );
lastAdded = d.getEnd();
// adding variable initializations
for ( JavaLocalDeclarationDescr.IdentifierDescr id : d.getIdentifiers() ) {
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();
}
}