Java tutorial
/************************************************************************************** * Copyright (c) Jonas Bonr, Alexandre Vasseur. All rights reserved. * * http://aspectwerkz.codehaus.org * * ---------------------------------------------------------------------------------- * * The software in this package is published under the terms of the LGPL license * * a copy of which has been included with this distribution in the license.txt file. * **************************************************************************************/ package org.codehaus.aspectwerkz.transform.inlining.weaver; import java.util.Set; import java.util.Iterator; import java.util.Collection; import org.objectweb.asm.*; import org.codehaus.aspectwerkz.transform.Context; import org.codehaus.aspectwerkz.transform.TransformationConstants; import org.codehaus.aspectwerkz.transform.inlining.ContextImpl; import org.codehaus.aspectwerkz.reflect.ClassInfo; import org.codehaus.aspectwerkz.expression.ExpressionContext; import org.codehaus.aspectwerkz.expression.PointcutType; import org.codehaus.aspectwerkz.expression.ExpressionInfo; import org.codehaus.aspectwerkz.definition.SystemDefinition; import org.codehaus.aspectwerkz.definition.AdviceDefinition; import org.codehaus.aspectwerkz.definition.DeploymentScope; import org.codehaus.aspectwerkz.DeploymentModel; import org.codehaus.aspectwerkz.perx.PerObjectAspect; /** * Adds an instance level aspect management to the target class. * * @author <a href="mailto:jboner@codehaus.org">Jonas Bonr </a> * @author <a href='mailto:the_mindstorm@evolva.ro'>Alexandru Popescu</a> */ public class InstanceLevelAspectVisitor extends ClassAdapter implements TransformationConstants { private final ContextImpl m_ctx; private final ClassInfo m_classInfo; private boolean m_isAdvised = false; /** * Creates a new add interface class adapter. * * @param cv * @param classInfo * @param ctx */ public InstanceLevelAspectVisitor(final ClassVisitor cv, final ClassInfo classInfo, final Context ctx) { super(cv); m_classInfo = classInfo; m_ctx = (ContextImpl) ctx; } /** * Visits the class. * * @param access * @param name * @param signature * @param superName * @param interfaces */ public void visit(final int version, final int access, final String name, final String signature, final String superName, final String[] interfaces) { if (classFilter(m_classInfo, m_ctx.getDefinitions())) { super.visit(version, access, name, signature, superName, interfaces); return; } for (int i = 0; i < interfaces.length; i++) { String anInterface = interfaces[i]; if (anInterface.equals(HAS_INSTANCE_LEVEL_ASPECT_INTERFACE_NAME)) { super.visit(version, access, name, signature, superName, interfaces); return; } } String[] newInterfaceArray = new String[interfaces.length + 1]; for (int i = 0; i < interfaces.length; i++) { newInterfaceArray[i] = interfaces[i]; } newInterfaceArray[interfaces.length] = HAS_INSTANCE_LEVEL_ASPECT_INTERFACE_NAME; // add the interface super.visit(version, access, name, signature, superName, newInterfaceArray); // add the field with the aspect instance map addAspectMapField(); // add the getAspect(..) method addGetAspectMethod(name); // add the hasAspect(...) method addHasAspectMethod(name); addBindAspectMethod(name); } /** * Appends mixin instantiation to the clinit method and/or init method. * * @param access * @param name * @param desc * @param signature * @param exceptions * @return */ public MethodVisitor visitMethod(final int access, final String name, final String desc, final String signature, final String[] exceptions) { if (m_isAdvised) { if (name.equals(INIT_METHOD_NAME)) { MethodVisitor mv = new AppendToInitMethodCodeAdapter( cv.visitMethod(access, name, desc, signature, exceptions), name); mv.visitMaxs(0, 0); return mv; } } return cv.visitMethod(access, name, desc, signature, exceptions); } /** * Adds the aspect map field to the target class. */ private void addAspectMapField() { super.visitField(ACC_PRIVATE + ACC_SYNTHETIC + ACC_TRANSIENT, INSTANCE_LEVEL_ASPECT_MAP_FIELD_NAME, INSTANCE_LEVEL_ASPECT_MAP_FIELD_SIGNATURE, null, null); } /** * Adds the getAspect(..) method to the target class. * * @param name the class name of the target class */ private void addGetAspectMethod(final String name) { MethodVisitor cv = super.visitMethod(ACC_PUBLIC + ACC_SYNTHETIC, INSTANCE_LEVEL_GETASPECT_METHOD_NAME, INSTANCE_LEVEL_GETASPECT_METHOD_SIGNATURE, null, null); cv.visitVarInsn(ALOAD, 0); cv.visitFieldInsn(GETFIELD, name, INSTANCE_LEVEL_ASPECT_MAP_FIELD_NAME, INSTANCE_LEVEL_ASPECT_MAP_FIELD_SIGNATURE); //-- cv.visitInsn(DUP); Label ifMapNonNull = new Label(); cv.visitJumpInsn(IFNONNULL, ifMapNonNull); cv.visitInsn(ACONST_NULL); cv.visitInsn(ARETURN); cv.visitLabel(ifMapNonNull); // // if == null, field = new HashMap() // Label ifFieldNullNotLabel = new Label(); // cv.visitJumpInsn(IFNONNULL, ifFieldNullNotLabel); // cv.visitVarInsn(ALOAD, 0); // cv.visitTypeInsn(NEW, HASH_MAP_CLASS_NAME); // cv.visitInsn(DUP); // cv.visitMethodInsn( // INVOKESPECIAL, // HASH_MAP_CLASS_NAME, // INIT_METHOD_NAME, // NO_PARAM_RETURN_VOID_SIGNATURE // ); // cv.visitFieldInsn( // PUTFIELD, // name, // INSTANCE_LEVEL_ASPECT_MAP_FIELD_NAME, // INSTANCE_LEVEL_ASPECT_MAP_FIELD_SIGNATURE // ); // cv.visitLabel(ifFieldNullNotLabel); // // cv.visitVarInsn(ALOAD, 0); // cv.visitFieldInsn( // GETFIELD, // name, // INSTANCE_LEVEL_ASPECT_MAP_FIELD_NAME, // INSTANCE_LEVEL_ASPECT_MAP_FIELD_SIGNATURE // ); // // cv.visitVarInsn(ALOAD, 2);//qName // cv.visitMethodInsn(INVOKEINTERFACE, MAP_CLASS_NAME, GET_METHOD_NAME, GET_METHOD_SIGNATURE); // cv.visitVarInsn(ASTORE, 4); // cv.visitVarInsn(ALOAD, 4); // Label ifNullNotLabel = new Label(); // cv.visitJumpInsn(IFNONNULL, ifNullNotLabel); // cv.visitVarInsn(ALOAD, 2);//qName // cv.visitVarInsn(ALOAD, 3);//containerClassName // cv.visitVarInsn(ALOAD, 0);//this (perInstance) // cv.visitMethodInsn( // INVOKESTATIC, // ASPECTS_CLASS_NAME, // ASPECT_OF_METHOD_NAME, // ASPECT_OF_PER_INSTANCE_METHOD_SIGNATURE // ); // cv.visitVarInsn(ASTORE, 4); //cv.visitVarInsn(ALOAD, 0); //-- cv.visitVarInsn(ALOAD, 1); cv.visitMethodInsn(INVOKEINTERFACE, MAP_CLASS_NAME, GET_METHOD_NAME, GET_METHOD_SIGNATURE); //-- // cv.visitFieldInsn( // GETFIELD, // name, // INSTANCE_LEVEL_ASPECT_MAP_FIELD_NAME, // INSTANCE_LEVEL_ASPECT_MAP_FIELD_SIGNATURE // ); cv.visitInsn(ARETURN); // cv.visitVarInsn(ALOAD, 2); // cv.visitVarInsn(ALOAD, 4); // cv.visitMethodInsn(INVOKEINTERFACE, MAP_CLASS_NAME, PUT_METHOD_NAME, PUT_METHOD_SIGNATURE); // cv.visitInsn(POP); // cv.visitLabel(ifNullNotLabel); // cv.visitVarInsn(ALOAD, 4); // cv.visitInsn(ARETURN); cv.visitMaxs(0, 0); m_ctx.markAsAdvised(); m_isAdvised = true; } private void addHasAspectMethod(String mapFieldName) { MethodVisitor cv = super.visitMethod(ACC_PUBLIC + ACC_SYNTHETIC, INSTANCE_LEVEL_HASASPECT_METHOD_NAME, INSTANCE_LEVEL_HASASPECT_METHOD_SIGNATURE, null, null); cv.visitVarInsn(ALOAD, 0); cv.visitFieldInsn(GETFIELD, mapFieldName, INSTANCE_LEVEL_ASPECT_MAP_FIELD_NAME, INSTANCE_LEVEL_ASPECT_MAP_FIELD_SIGNATURE); cv.visitInsn(DUP); Label ifMapNonNull = new Label(); cv.visitJumpInsn(IFNONNULL, ifMapNonNull); cv.visitInsn(ICONST_0); cv.visitInsn(IRETURN); cv.visitLabel(ifMapNonNull); cv.visitVarInsn(ALOAD, 1); cv.visitMethodInsn(INVOKEINTERFACE, MAP_CLASS_NAME, "containsKey", "(Ljava/lang/Object;)Z"); //cv.visitMethodInsn(INVOKEINTERFACE, MAP_CLASS_NAME, GET_METHOD_NAME, GET_METHOD_SIGNATURE); // // Label ifNullLabel = new Label(); // cv.visitJumpInsn(IFNULL, ifNullLabel); // cv.visitInsn(ICONST_1); // cv.visitInsn(IRETURN); // cv.visitLabel(ifNullLabel); // cv.visitInsn(ICONST_0); cv.visitInsn(IRETURN); cv.visitMaxs(0, 0); m_ctx.markAsAdvised(); m_isAdvised = true; } private void addBindAspectMethod(final String name) { MethodVisitor cv = super.visitMethod(ACC_PUBLIC + ACC_SYNTHETIC, INSTANCE_LEVEL_BINDASPECT_METHOD_NAME, INSTANCE_LEVEL_BINDASPECT_METHOD_SIGNATURE, null, null); cv.visitVarInsn(ALOAD, 0); cv.visitFieldInsn(GETFIELD, name, INSTANCE_LEVEL_ASPECT_MAP_FIELD_NAME, INSTANCE_LEVEL_ASPECT_MAP_FIELD_SIGNATURE); // if == null, field = new HashMap() Label ifFieldNullNotLabel = new Label(); cv.visitJumpInsn(IFNONNULL, ifFieldNullNotLabel); cv.visitVarInsn(ALOAD, 0); cv.visitTypeInsn(NEW, HASH_MAP_CLASS_NAME); cv.visitInsn(DUP); cv.visitMethodInsn(INVOKESPECIAL, HASH_MAP_CLASS_NAME, INIT_METHOD_NAME, NO_PARAM_RETURN_VOID_SIGNATURE); cv.visitFieldInsn(PUTFIELD, name, INSTANCE_LEVEL_ASPECT_MAP_FIELD_NAME, INSTANCE_LEVEL_ASPECT_MAP_FIELD_SIGNATURE); cv.visitLabel(ifFieldNullNotLabel); cv.visitVarInsn(ALOAD, 0); cv.visitFieldInsn(GETFIELD, name, INSTANCE_LEVEL_ASPECT_MAP_FIELD_NAME, INSTANCE_LEVEL_ASPECT_MAP_FIELD_SIGNATURE); cv.visitVarInsn(ALOAD, 1); cv.visitVarInsn(ALOAD, 2); cv.visitMethodInsn(INVOKEINTERFACE, MAP_CLASS_NAME, PUT_METHOD_NAME, PUT_METHOD_SIGNATURE); cv.visitVarInsn(ALOAD, 2); cv.visitInsn(ARETURN); } /** * Filters the classes to be transformed. * * @param classInfo the class to filter * @param definitions a set with the definitions * @return boolean true if the method should be filtered away */ public static boolean classFilter(final ClassInfo classInfo, final Set definitions) { if (classInfo.isInterface()) { return true; } ExpressionContext ctx = new ExpressionContext(PointcutType.WITHIN, null, classInfo); for (Iterator it = definitions.iterator(); it.hasNext();) { SystemDefinition systemDef = (SystemDefinition) it.next(); String className = classInfo.getName().replace('/', '.'); if (systemDef.inExcludePackage(className)) { return true; } if (!systemDef.inIncludePackage(className)) { return true; } Collection adviceDefs = systemDef.getAdviceDefinitions(); for (Iterator defs = adviceDefs.iterator(); defs.hasNext();) { AdviceDefinition adviceDef = (AdviceDefinition) defs.next(); ExpressionInfo expressionInfo = adviceDef.getExpressionInfo(); if (expressionInfo == null) { continue; } DeploymentModel deploymentModel = adviceDef.getDeploymentModel(); // match on perinstance deployed aspects if (DeploymentModel.PER_INSTANCE.equals(deploymentModel)) { if (expressionInfo.getAdvisedClassFilterExpression().match(ctx)) { return false; } } // match on perthis/pertarget perX X pointcuts if (adviceDef.getAspectClassName().equals(PerObjectAspect.PEROBJECT_ASPECT_NAME)) { ExpressionInfo perXExpressionInfo = adviceDef.getExpressionInfo(); if (perXExpressionInfo.getAdvisedClassFilterExpression().match(ctx)) { return false; } } } // match on deployment scopes, e.g. potential perinstance deployment aspects Collection deploymentScopes = systemDef.getDeploymentScopes(); for (Iterator scopes = deploymentScopes.iterator(); scopes.hasNext();) { DeploymentScope deploymentScope = (DeploymentScope) scopes.next(); ExpressionInfo expression = new ExpressionInfo(deploymentScope.getExpression(), systemDef.getUuid()); if (expression.getAdvisedClassFilterExpression().match(ctx)) { return false; } } } return true; } /** * Adds initialization of aspect map field to end of the init method. * * @author <a href="mailto:jboner@codehaus.org">Jonas Bonr </a> */ private class AppendToInitMethodCodeAdapter extends AfterObjectInitializationCodeAdapter { private boolean m_done = false; public AppendToInitMethodCodeAdapter(final MethodVisitor ca, String callerMemberName) { super(ca, callerMemberName); } /** * Inserts the init of the aspect field right after the call to super(..) of this(..). * * @param opcode * @param owner * @param name * @param desc */ public void visitMethodInsn(int opcode, String owner, String name, String desc) { super.visitMethodInsn(opcode, owner, name, desc); if (opcode == INVOKESPECIAL && m_isObjectInitialized && !m_done) { m_done = true; // initialize aspect map field mv.visitVarInsn(ALOAD, 0); mv.visitTypeInsn(NEW, HASH_MAP_CLASS_NAME); mv.visitInsn(DUP); mv.visitMethodInsn(INVOKESPECIAL, HASH_MAP_CLASS_NAME, INIT_METHOD_NAME, NO_PARAM_RETURN_VOID_SIGNATURE); mv.visitFieldInsn(PUTFIELD, m_classInfo.getName().replace('.', '/'), INSTANCE_LEVEL_ASPECT_MAP_FIELD_NAME, INSTANCE_LEVEL_ASPECT_MAP_FIELD_SIGNATURE); } } } }