/*
* Copyright 2011 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.core.factmodel.traits;
import org.drools.core.factmodel.AnnotationDefinition;
import org.drools.core.factmodel.BuildUtils;
import org.drools.core.factmodel.ClassDefinition;
import org.drools.core.factmodel.FieldDefinition;
import org.drools.core.rule.builder.dialect.asm.ClassGenerator;
import org.mvel2.asm.AnnotationVisitor;
import org.mvel2.asm.ClassWriter;
import org.mvel2.asm.MethodVisitor;
import org.mvel2.asm.Type;
import java.io.Serializable;
import java.util.Iterator;
import java.util.List;
public class TraitClassBuilderImpl implements TraitClassBuilder, Serializable {
public byte[] buildClass( ClassDefinition classDef ) {
init( classDef );
ClassWriter cw = new ClassWriter( ClassWriter.COMPUTE_MAXS );
try {
String cName = BuildUtils.getInternalType(classDef.getClassName());
String genericTypes = BuildUtils.getGenericTypes( classDef.getInterfaces() );
String superType = Type.getInternalName( Object.class );
String[] intfaces = null;
if ( Object.class.getName().equals( classDef.getSuperClass() ) ) {
String[] tmp = BuildUtils.getInternalTypes( classDef.getInterfaces() );
intfaces = new String[ tmp.length + 1 ];
System.arraycopy( tmp, 0, intfaces, 0, tmp.length );
intfaces[ tmp.length ] = Type.getInternalName( Serializable.class );
} else {
String[] tmp = BuildUtils.getInternalTypes( classDef.getInterfaces() );
intfaces = new String[ tmp.length + 2 ];
System.arraycopy( tmp, 0, intfaces, 0, tmp.length );
intfaces[ tmp.length ] = BuildUtils.getInternalType( classDef.getSuperClass() );
intfaces[ tmp.length + 1 ] = Type.getInternalName( Serializable.class );
}
cw.visit( ClassGenerator.JAVA_VERSION, ACC_PUBLIC + ACC_ABSTRACT + ACC_INTERFACE,
cName,
genericTypes,
superType,
intfaces );
{
if ( classDef.getDefinedClass() == null || classDef.getDefinedClass().getAnnotation( Trait.class ) == null ) {
AnnotationVisitor av0 = cw.visitAnnotation( Type.getDescriptor( Trait.class ), true);
List<AnnotationDefinition> annotations = classDef.getAnnotations();
if ( annotations != null && ! annotations.isEmpty() ) {
for ( Iterator<AnnotationDefinition> iter = annotations.iterator(); iter.hasNext(); ) {
AnnotationDefinition adef = iter.next();
if ( Trait.class.getName().equals( adef.getName() ) ) {
if ( adef.getPropertyValue( "logical" ) != null ) {
av0.visit( "logical", (Boolean) adef.getPropertyValue( "logical" ) );
}
if ( adef.getPropertyValue( "impl" ) != null ) {
av0.visit( "impl", Type.getType( (Class) adef.getPropertyValue( "impl" ) ) );
}
break;
}
}
}
av0.visitEnd();
}
}
for ( FieldDefinition field : classDef.getFieldsDefinitions() ) {
buildField( cw, field );
}
finalizeCreation( classDef );
cw.visitEnd();
} catch ( Exception e ) {
e.printStackTrace();
}
return cw.toByteArray();
}
protected void init( ClassDefinition classDef ) {
}
private void buildField( ClassWriter cw, FieldDefinition field ) {
String name = field.getName();
name = name.substring( 0,1 ).toUpperCase() + name.substring( 1 );
String type = field.getTypeName();
buildGetter( cw, field, name, type, null );
buildSetter( cw, field, name, type, null );
}
protected void buildSetter( ClassWriter cw, FieldDefinition field, String name, String type, String generic ) {
MethodVisitor mv = cw.visitMethod( ACC_PUBLIC + ACC_ABSTRACT,
BuildUtils.setterName( name, type ),
"(" + BuildUtils.getTypeDescriptor( type ) + ")V",
generic == null ? null :
"(" + BuildUtils.getTypeDescriptor( type ).replace( ";", "<" + BuildUtils.getTypeDescriptor( generic ) + ">;") + ")V",
null );
mv.visitEnd();
}
protected void buildGetter( ClassWriter cw, FieldDefinition field, String name, String type, String generic ) {
name = name.substring( 0, 1 ).toUpperCase() + name.substring( 1 );
MethodVisitor mv = cw.visitMethod( ACC_PUBLIC + ACC_ABSTRACT,
BuildUtils.getterName( name, type ),
"()" + BuildUtils.getTypeDescriptor( type ),
generic == null ? null :
"()" + BuildUtils.getTypeDescriptor( type ).replace( ";", "<" + BuildUtils.getTypeDescriptor( generic ) + ">;" ),
null );
mv.visitEnd();
}
protected void finalizeCreation(ClassDefinition trait) {
}
}