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.compiler; import org.objectweb.asm.MethodVisitor; import org.objectweb.asm.Type; import org.codehaus.aspectwerkz.transform.TransformationUtil; import org.codehaus.aspectwerkz.transform.inlining.AsmHelper; import java.lang.reflect.Modifier; /** * A compiler that compiles/generates a class that represents a specific join point, a class which invokes the advices * and the target join point statically. * * @author <a href="mailto:jboner@codehaus.org">Jonas Bonr </a> * @author <a href="mailto:alex AT gnilux DOT com">Alexandre Vasseur </a> */ public class FieldGetJoinPointCompiler extends AbstractJoinPointCompiler { /** * Creates a new join point compiler instance. * * @param model */ FieldGetJoinPointCompiler(final CompilationInfo.Model model) { super(model); } /** * Creates join point specific fields. */ protected void createJoinPointSpecificFields() { String[] fieldNames = null; // create the field argument field Type fieldType = Type.getType(m_calleeMemberDesc); fieldNames = new String[1]; String fieldName = ARGUMENT_FIELD + 0; fieldNames[0] = fieldName; m_cw.visitField(ACC_PRIVATE, fieldName, fieldType.getDescriptor(), null, null); m_fieldNames = fieldNames; m_cw.visitField(ACC_PRIVATE + ACC_STATIC, SIGNATURE_FIELD_NAME, FIELD_SIGNATURE_IMPL_CLASS_SIGNATURE, null, null); } /** * Creates the signature for the join point. * <p/> * FIXME signature field should NOT be of type Signature but of the specific type (update all refs as well) * * @param cv */ protected void createSignature(final MethodVisitor cv) { cv.visitFieldInsn(GETSTATIC, m_joinPointClassName, TARGET_CLASS_FIELD_NAME_IN_JP, CLASS_CLASS_SIGNATURE); cv.visitLdcInsn(new Integer(m_joinPointHash)); cv.visitMethodInsn(INVOKESTATIC, SIGNATURE_FACTORY_CLASS, NEW_FIELD_SIGNATURE_METHOD_NAME, NEW_FIELD_SIGNATURE_METHOD_SIGNATURE); cv.visitFieldInsn(PUTSTATIC, m_joinPointClassName, SIGNATURE_FIELD_NAME, FIELD_SIGNATURE_IMPL_CLASS_SIGNATURE); } /** * Optimized implementation that does not retrieve the parameters from the join point instance but is passed * directly to the method from the input parameters in the 'invoke' method. Can only be used if no around advice * exists. * * @param cv * @param input */ protected void createInlinedJoinPointInvocation(final MethodVisitor cv, final CompilerInput input) { // load the target instance (arg0 else not available for static target) if (!Modifier.isStatic(m_calleeMemberModifiers)) { cv.visitVarInsn(ALOAD, 0); } // do we have a public field ? If so don't use the wrappers if (Modifier.isPublic(m_calleeMemberModifiers)) { if (Modifier.isStatic(m_calleeMemberModifiers)) { cv.visitFieldInsn(GETSTATIC, m_calleeClassName, m_calleeMemberName, m_calleeMemberDesc); } else { cv.visitFieldInsn(GETFIELD, m_calleeClassName, m_calleeMemberName, m_calleeMemberDesc); } } else { // use the wrapper String joinPointName = TransformationUtil.getWrapperMethodName(m_calleeMemberName, m_calleeMemberDesc, m_calleeClassName, GETFIELD_WRAPPER_METHOD_PREFIX); StringBuffer getFieldWrapperDesc = new StringBuffer(); getFieldWrapperDesc.append('('); getFieldWrapperDesc.append(')'); getFieldWrapperDesc.append(m_calleeMemberDesc); if (Modifier.isStatic(m_calleeMemberModifiers)) { cv.visitMethodInsn(INVOKESTATIC, m_calleeClassName, joinPointName, getFieldWrapperDesc.toString()); } else { cv.visitMethodInsn(INVOKEVIRTUAL, m_calleeClassName, joinPointName, getFieldWrapperDesc.toString()); } } } /** * Creates a call to the target join point, the parameter(s) to the join point are retrieved from the invocation * local join point instance. * * @param cv */ protected void createJoinPointInvocation(final MethodVisitor cv) { // load the target instance member field unless calleeMember is static if (!Modifier.isStatic(m_calleeMemberModifiers)) { cv.visitVarInsn(ALOAD, 0); cv.visitFieldInsn(GETFIELD, m_joinPointClassName, CALLEE_INSTANCE_FIELD_NAME, m_calleeClassSignature); } // do we have a public field ? If so don't use the wrappers if (Modifier.isPublic(m_calleeMemberModifiers)) { if (Modifier.isStatic(m_calleeMemberModifiers)) { cv.visitFieldInsn(GETSTATIC, m_calleeClassName, m_calleeMemberName, m_calleeMemberDesc); } else { cv.visitFieldInsn(GETFIELD, m_calleeClassName, m_calleeMemberName, m_calleeMemberDesc); } } else { String joinPointName = TransformationUtil.getWrapperMethodName(m_calleeMemberName, m_calleeMemberDesc, m_calleeClassName, GETFIELD_WRAPPER_METHOD_PREFIX); StringBuffer getFieldWrapperDesc = new StringBuffer(); getFieldWrapperDesc.append('('); getFieldWrapperDesc.append(')'); getFieldWrapperDesc.append(m_calleeMemberDesc); if (Modifier.isStatic(m_calleeMemberModifiers)) { cv.visitMethodInsn(INVOKESTATIC, m_calleeClassName, joinPointName, getFieldWrapperDesc.toString()); } else { cv.visitMethodInsn(INVOKEVIRTUAL, m_calleeClassName, joinPointName, getFieldWrapperDesc.toString()); } } } /** * Returns the join points return type. * * @return */ protected Type getJoinPointReturnType() { return Type.getType(m_calleeMemberDesc); } /** * Returns the join points argument type(s). * * @return */ protected Type[] getJoinPointArgumentTypes() { return new Type[] { Type.getType(m_calleeMemberDesc) }; } /** * Creates the getRtti method */ protected void createGetRttiMethod() { MethodVisitor cv = m_cw.visitMethod(ACC_PUBLIC, GET_RTTI_METHOD_NAME, GET_RTTI_METHOD_SIGNATURE, null, null); // new FieldRttiImpl( .. ) cv.visitTypeInsn(NEW, FIELD_RTTI_IMPL_CLASS_NAME); cv.visitInsn(DUP); cv.visitFieldInsn(GETSTATIC, m_joinPointClassName, SIGNATURE_FIELD_NAME, FIELD_SIGNATURE_IMPL_CLASS_SIGNATURE); cv.visitVarInsn(ALOAD, 0); cv.visitFieldInsn(GETFIELD, m_joinPointClassName, CALLER_INSTANCE_FIELD_NAME, m_callerClassSignature); cv.visitVarInsn(ALOAD, 0); cv.visitFieldInsn(GETFIELD, m_joinPointClassName, CALLEE_INSTANCE_FIELD_NAME, m_calleeClassSignature); cv.visitMethodInsn(INVOKESPECIAL, FIELD_RTTI_IMPL_CLASS_NAME, INIT_METHOD_NAME, FIELD_RTTI_IMPL_INIT_SIGNATURE); // set the value cv.visitInsn(DUP); if (AsmHelper.isPrimitive(m_returnType)) { AsmHelper.prepareWrappingOfPrimitiveType(cv, m_returnType); cv.visitVarInsn(ALOAD, 0); cv.visitFieldInsn(GETFIELD, m_joinPointClassName, RETURN_VALUE_FIELD_NAME, m_returnType.getDescriptor()); AsmHelper.wrapPrimitiveType(cv, m_returnType); } else { cv.visitVarInsn(ALOAD, 0); cv.visitFieldInsn(GETFIELD, m_joinPointClassName, RETURN_VALUE_FIELD_NAME, m_returnType.getDescriptor()); } cv.visitMethodInsn(INVOKEVIRTUAL, FIELD_RTTI_IMPL_CLASS_NAME, SET_FIELD_VALUE_METHOD_NAME, SET_FIELD_VALUE_METHOD_SIGNATURE); cv.visitInsn(ARETURN); cv.visitMaxs(0, 0); } /** * Creates the getSignature method. */ protected void createGetSignatureMethod() { MethodVisitor cv = m_cw.visitMethod(ACC_PUBLIC, GET_SIGNATURE_METHOD_NAME, GET_SIGNATURE_METHOD_SIGNATURE, null, null); cv.visitFieldInsn(GETSTATIC, m_joinPointClassName, SIGNATURE_FIELD_NAME, FIELD_SIGNATURE_IMPL_CLASS_SIGNATURE); cv.visitInsn(ARETURN); cv.visitMaxs(0, 0); } }