/**********************************************************************
Copyright (c) 2004 Kikuchi Kousuke and others. All rights reserved.
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.
Contributors:
2005 Andy Jefferson - changed to use "detachedState"
...
**********************************************************************/
package org.jpox.enhancer.bcel.method;
import org.apache.bcel.Constants;
import org.apache.bcel.generic.ArrayType;
import org.apache.bcel.generic.BranchInstruction;
import org.apache.bcel.generic.CHECKCAST;
import org.apache.bcel.generic.IFLE;
import org.apache.bcel.generic.IFNE;
import org.apache.bcel.generic.IFNULL;
import org.apache.bcel.generic.IF_ICMPEQ;
import org.apache.bcel.generic.InstructionConstants;
import org.apache.bcel.generic.InstructionFactory;
import org.apache.bcel.generic.InstructionHandle;
import org.apache.bcel.generic.ReferenceType;
import org.apache.bcel.generic.Type;
import org.jpox.enhancer.ClassEnhancer;
import org.jpox.enhancer.bcel.BCELClassEnhancer;
import org.jpox.enhancer.bcel.BCELClassMethod;
import org.jpox.enhancer.bcel.BCELUtils;
import org.jpox.enhancer.bcel.metadata.BCELMember;
import org.jpox.enhancer.bcel.metadata.BCELFieldPropertyMetaData;
/**
* Create CHECK_READ method.
* @version $Revision: 1.7 $
*/
public class CheckReadMethod extends BCELClassMethod
{
/** target field */
protected BCELFieldPropertyMetaData fieldConfig;
/**
* Constructor
* @param methodName method name
* @param type method modifier
* @param resultType return type
* @param argType argment types
* @param argName argment names
* @param synthetic synthetic flag
* @param gen target class generator
* @param fieldConfig target field.
*/
public CheckReadMethod(
String methodName,
int type,
Type resultType,
Type[] argType,
String[] argName,
boolean synthetic,
BCELClassEnhancer gen,
BCELFieldPropertyMetaData fieldConfig)
{
super(methodName, type, resultType, argType, argName, synthetic, gen);
this.fieldConfig = fieldConfig;
}
public void execute()
{
InstructionHandle jumpTarget;
BCELMember targetField = fieldConfig.getEnhanceField();
Type smType = BCELUtils.getJDOMethodType(targetField.getType());
Type nativeType = targetField.getType();
String fieldName = targetField.getName();
il.append(InstructionConstants.ALOAD_0);
il.append(factory.createGetField(className, ClassEnhancer.FN_Flag, Type.BYTE));
BranchInstruction jump1 = new IFLE(null);
il.append(jump1);
il.append(InstructionConstants.ALOAD_0);
il.append(factory.createGetField(className, ClassEnhancer.FN_StateManager, BCELClassEnhancer.OT_StateManager));
BranchInstruction jump2 = new IFNULL(null);
il.append(jump2);
il.append(InstructionConstants.ALOAD_0);
il.append(factory.createGetField(className, ClassEnhancer.FN_StateManager, BCELClassEnhancer.OT_StateManager));
il.append(InstructionConstants.ALOAD_0);
il.append(BCELUtils.getBIPUSH(fieldConfig.getFieldId()));
if (cmd.getPersistenceCapableSuperclass() != null)
{
il.append(factory.createGetStatic(className, ClassEnhancer.FN_JdoInheritedFieldCount, Type.INT));
il.append(InstructionConstants.IADD);
}
il.append(factory.createInvoke(ClassEnhancer.CN_StateManager, "isLoaded", Type.BOOLEAN,
new Type[]{BCELClassEnhancer.OT_PersistenceCapable, Type.INT}, Constants.INVOKEINTERFACE));
BranchInstruction jump3 = new IFNE(null);
il.append(jump3);
// statemanager.getXXXfield();
il.append(InstructionConstants.ALOAD_0);
il.append(factory.createGetField(className, ClassEnhancer.FN_StateManager, BCELClassEnhancer.OT_StateManager));
il.append(InstructionConstants.ALOAD_0);
il.append(BCELUtils.getBIPUSH(fieldConfig.getFieldId()));
if (cmd.getPersistenceCapableSuperclass() != null)
{
il.append(factory.createGetStatic(className, ClassEnhancer.FN_JdoInheritedFieldCount, Type.INT));
il.append(InstructionConstants.IADD);
}
il.append(InstructionConstants.ALOAD_0);
il.append(factory.createGetField(className, fieldName, nativeType));
il.append(factory.createInvoke(ClassEnhancer.CN_StateManager, "get" + BCELUtils.getJDOMethodName(targetField.getType()) + "Field",
smType, new Type[]{BCELClassEnhancer.OT_PersistenceCapable, Type.INT, smType}, Constants.INVOKEINTERFACE));
if (nativeType instanceof ReferenceType)
{
String type = null;
if (nativeType instanceof ArrayType)
type = nativeType.getSignature();
else
type = nativeType.toString();
il.append(new CHECKCAST(constantPoolGen.addClass(type)));
}
il.append(InstructionFactory.createReturn(nativeType));
//----detach------
if (cmd.isDetachable())
{
// jdoIsDetached()
jumpTarget = il.append(InstructionConstants.ALOAD_0);
il.append(factory.createInvoke(ClassEnhancer.CN_PersistenceCapable, ClassEnhancer.MN_JdoIsDetached,
Type.BOOLEAN, Type.NO_ARGS, Constants.INVOKEINTERFACE));
//0
il.append(InstructionConstants.ICONST_0);
// if (jdoIsDetached() == 0)
IF_ICMPEQ ifIsDetached = new IF_ICMPEQ(null);
il.append(ifIsDetached);
// if (jdoDetachedState[2].get(?) == 1)
// jdoDetachedState[2]
ifIsDetached.setTarget(il.append(InstructionConstants.ALOAD_0));
il.append(factory.createGetField(className, ClassEnhancer.FN_JdoDetachedState, BCELClassEnhancer.OT_ObjectArray));
il.append(InstructionConstants.ICONST_2);
il.append(InstructionConstants.AALOAD);
il.append(factory.createCheckCast(BCELClassEnhancer.OT_BitSet)); // Cast to BitSet
// the field index: 0, 1, 2...
il.append(BCELUtils.getBIPUSH(fieldConfig.getFieldId()));
if (cmd.getPersistenceCapableSuperclass() != null)
{
// add to field index the parentFieldCount
il.append(factory.createGetStatic(className, ClassEnhancer.FN_JdoInheritedFieldCount, Type.INT));
il.append(InstructionConstants.IADD);
}
// get(?)
il.append(factory.createInvoke(ClassEnhancer.CN_BitSet, "get", Type.BOOLEAN, new Type[]{Type.INT}, Constants.INVOKEVIRTUAL));
// 1
il.append(InstructionConstants.ICONST_1);
// if (jdoLoadedFields.get(?) == 1)
IF_ICMPEQ ifLoaded = new IF_ICMPEQ(null);
il.append(ifLoaded);
// throw new JDODetachedFieldAccessException("XXXX was not loaded.");
createThrowException(ClassEnhancer.CN_JDODetachedFieldAccessException, LOCALISER.msg("Enhancer.DetachedFieldAccess", fieldName));
//----detach------
// return <target field>
InstructionHandle jumpTarget2;
jumpTarget2 = il.append(InstructionConstants.ALOAD_0);
il.append(factory.createGetField(className, fieldName, nativeType));
il.append(InstructionFactory.createReturn(nativeType));
jump1.setTarget(jumpTarget);
jump2.setTarget(jumpTarget);
jump3.setTarget(jumpTarget);
ifIsDetached.setTarget(jumpTarget2);
ifLoaded.setTarget(jumpTarget2);
}
else
{
// return <target field>
jumpTarget = il.append(InstructionConstants.ALOAD_0);
il.append(factory.createGetField(className, fieldName, nativeType));
il.append(InstructionFactory.createReturn(nativeType));
jump1.setTarget(jumpTarget);
jump2.setTarget(jumpTarget);
jump3.setTarget(jumpTarget);
}
}
}