// Copyright 2011 The Apache Software Foundation
//
// 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.apache.tapestry5.ioc.internal.services;
import java.lang.reflect.Constructor;
import java.lang.reflect.Member;
import java.lang.reflect.Method;
import java.util.List;
import org.apache.tapestry5.internal.plastic.PlasticInternalUtils;
import org.apache.tapestry5.internal.plastic.asm.Type;
import org.apache.tapestry5.internal.plastic.asm.tree.AbstractInsnNode;
import org.apache.tapestry5.internal.plastic.asm.tree.ClassNode;
import org.apache.tapestry5.internal.plastic.asm.tree.InsnList;
import org.apache.tapestry5.internal.plastic.asm.tree.LineNumberNode;
import org.apache.tapestry5.internal.plastic.asm.tree.MethodNode;
import org.apache.tapestry5.ioc.Location;
import org.apache.tapestry5.ioc.ObjectCreator;
import org.apache.tapestry5.ioc.internal.util.InternalUtils;
import org.apache.tapestry5.ioc.services.PlasticProxyFactory;
import org.apache.tapestry5.plastic.ClassInstantiator;
import org.apache.tapestry5.plastic.InstructionBuilder;
import org.apache.tapestry5.plastic.InstructionBuilderCallback;
import org.apache.tapestry5.plastic.PlasticClass;
import org.apache.tapestry5.plastic.PlasticClassListener;
import org.apache.tapestry5.plastic.PlasticClassTransformation;
import org.apache.tapestry5.plastic.PlasticClassTransformer;
import org.apache.tapestry5.plastic.PlasticField;
import org.apache.tapestry5.plastic.PlasticManager;
import org.apache.tapestry5.plastic.PlasticMethod;
import org.slf4j.Logger;
public class PlasticProxyFactoryImpl implements PlasticProxyFactory
{
private final Logger logger;
private final PlasticManager manager;
private final ClassLoader loader;
public PlasticProxyFactoryImpl(ClassLoader parentClassLoader, Logger logger)
{
this.loader = parentClassLoader;
this.logger = logger;
manager = PlasticManager.withClassLoader(parentClassLoader).create();
if (logger != null)
{
manager.addPlasticClassListener(new PlasticClassListenerLogger(logger));
}
}
public ClassLoader getClassLoader()
{
return manager.getClassLoader();
}
public <T> ClassInstantiator<T> createProxy(Class<T> interfaceType, PlasticClassTransformer callback)
{
return manager.createProxy(interfaceType, callback);
}
public PlasticClassTransformation createProxyTransformation(Class interfaceType)
{
return manager.createProxyTransformation(interfaceType);
}
public <T> T createProxy(final Class<T> interfaceType, final ObjectCreator<T> creator, final String description)
{
assert creator != null;
assert InternalUtils.isNonBlank(description);
ClassInstantiator<T> instantiator = createProxy(interfaceType, new PlasticClassTransformer()
{
public void transform(PlasticClass plasticClass)
{
final PlasticField objectCreatorField = plasticClass.introduceField(ObjectCreator.class, "creator")
.inject(creator);
PlasticMethod delegateMethod = plasticClass.introducePrivateMethod(interfaceType.getName(), "delegate",
null, null);
delegateMethod.changeImplementation(new InstructionBuilderCallback()
{
public void doBuild(InstructionBuilder builder)
{
builder.loadThis().getField(objectCreatorField);
builder.invoke(ObjectCreator.class, Object.class, "createObject");
builder.checkcast(interfaceType).returnResult();
}
});
for (Method method : interfaceType.getMethods())
{
plasticClass.introduceMethod(method).delegateTo(delegateMethod);
}
plasticClass.addToString(description);
}
});
return interfaceType.cast(instantiator.newInstance());
}
private ClassNode readClassNode(Class clazz)
{
byte[] bytecode = PlasticInternalUtils.readBytecodeForClass(loader, clazz.getName(), false);
return bytecode == null ? null : PlasticInternalUtils.convertBytecodeToClassNode(bytecode);
}
public Location getMethodLocation(Method method)
{
return getMemberLocation(method, method.getName(), Type.getMethodDescriptor(method),
InternalUtils.asString(method));
}
public Location getConstructorLocation(Constructor constructor)
{
StringBuilder builder = new StringBuilder(constructor.getDeclaringClass().getName()).append("(");
String sep = "";
for (Class parameterType : constructor.getParameterTypes())
{
builder.append(sep);
builder.append(parameterType.getSimpleName());
sep = ", ";
}
builder.append(")");
String constructorDescription = builder.toString();
Location location = getMemberLocation(constructor, "<init>", Type.getConstructorDescriptor(constructor),
constructorDescription);
if (location != null)
return location;
return new StringLocation(builder.toString(), 0);
}
public Location getMemberLocation(Member member, String methodName, String memberTypeDesc, String textDescription)
{
ClassNode classNode = readClassNode(member.getDeclaringClass());
if (classNode == null)
return null;
if (classNode.sourceFile == null)
return null;
for (MethodNode mn : (List<MethodNode>) classNode.methods)
{
if (mn.name.equals(methodName) && mn.desc.equals(memberTypeDesc))
{
int lineNumber = findFirstLineNumber(mn.instructions);
if (lineNumber < 1)
return null;
String description = String.format("%s (at %s:%d)", textDescription, classNode.sourceFile, lineNumber);
return new StringLocation(description, lineNumber);
}
}
// Didn't find it. Odd.
return null;
}
private int findFirstLineNumber(InsnList instructions)
{
for (AbstractInsnNode node = instructions.getFirst(); node != null; node = node.getNext())
{
if (node instanceof LineNumberNode) { return ((LineNumberNode) node).line; }
}
return -1;
}
public void addPlasticClassListener(PlasticClassListener listener)
{
manager.addPlasticClassListener(listener);
}
public void removePlasticClassListener(PlasticClassListener listener)
{
manager.removePlasticClassListener(listener);
}
}