package org.apache.maven.shared.dependency.analyzer.asm;
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
import org.objectweb.asm.AnnotationVisitor;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
import org.objectweb.asm.signature.SignatureReader;
import org.objectweb.asm.signature.SignatureVisitor;
/**
* Computes the set of classes referenced by visited code.
* Inspired by <code>org.objectweb.asm.depend.DependencyVisitor</code> in the ASM dependencies example.
*
* @author <a href="mailto:markhobson@gmail.com">Mark Hobson</a>
* @version $Id$
*/
public class DefaultMethodVisitor
extends MethodVisitor
{
private final AnnotationVisitor annotationVisitor;
private final SignatureVisitor signatureVisitor;
private final ResultCollector resultCollector;
public DefaultMethodVisitor( AnnotationVisitor annotationVisitor, SignatureVisitor signatureVisitor,
ResultCollector resultCollector )
{
super( Opcodes.ASM5 );
this.annotationVisitor = annotationVisitor;
this.signatureVisitor = signatureVisitor;
this.resultCollector = resultCollector;
}
public AnnotationVisitor visitAnnotation( final String desc, final boolean visible )
{
resultCollector.addDesc( desc );
return annotationVisitor;
}
public AnnotationVisitor visitParameterAnnotation( final int parameter, final String desc, final boolean visible )
{
resultCollector.addDesc( desc );
return annotationVisitor;
}
public void visitTypeInsn( final int opcode, final String desc )
{
if ( desc.charAt( 0 ) == '[' )
{
resultCollector.addDesc( desc );
}
else
{
resultCollector.addName( desc );
}
}
public void visitFieldInsn( final int opcode, final String owner, final String name, final String desc )
{
resultCollector.addName( owner );
/*
* NOTE: Merely accessing a field does not impose a direct dependency on its type. For example, the code line
* <code>java.lang.Object var = bean.field;</code> does not directly depend on the type of the field. A direct
* dependency is only introduced when the code explicitly references the field's type by means of a variable
* declaration or a type check/cast. Those cases are handled by other visitor callbacks.
*/
}
@Override
public void visitMethodInsn( int opcode, String owner, String name, String desc, boolean itf )
{
resultCollector.addName( owner );
}
public void visitLdcInsn( final Object cst )
{
if ( cst instanceof Type )
{
resultCollector.addType( (Type) cst );
}
}
public void visitMultiANewArrayInsn( final String desc, final int dims )
{
resultCollector.addDesc( desc );
}
public void visitTryCatchBlock( final Label start, final Label end, final Label handler, final String type )
{
resultCollector.addName( type );
}
public void visitLocalVariable( final String name, final String desc, final String signature, final Label start,
final Label end, final int index )
{
if ( signature == null )
{
resultCollector.addDesc( desc );
}
else
{
addTypeSignature( signature );
}
}
private void addTypeSignature( final String signature )
{
if ( signature != null )
{
new SignatureReader( signature ).acceptType( signatureVisitor );
}
}
}