/*
* JBoss, Home of Professional Open Source
* Copyright 2008, Red Hat, Inc. and/or its affiliates, and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* 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.jboss.weld.bean.proxy;
import static org.jboss.weld.util.reflection.Reflections.cast;
import java.io.File;
import java.io.IOException;
import java.io.Serializable;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.Type;
import java.nio.file.Files;
import java.nio.file.StandardOpenOption;
import java.security.AccessController;
import java.security.PrivilegedActionException;
import java.security.ProtectionDomain;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;
import javax.enterprise.inject.spi.Bean;
import org.jboss.classfilewriter.AccessFlag;
import org.jboss.classfilewriter.ClassFile;
import org.jboss.classfilewriter.ClassMethod;
import org.jboss.classfilewriter.DuplicateMemberException;
import org.jboss.classfilewriter.code.BranchEnd;
import org.jboss.classfilewriter.code.CodeAttribute;
import org.jboss.weld.Container;
import org.jboss.weld.SystemPropertiesConfiguration;
import org.jboss.weld.exceptions.DefinitionException;
import org.jboss.weld.exceptions.WeldException;
import org.jboss.weld.interceptor.proxy.LifecycleMixin;
import org.jboss.weld.interceptor.util.proxy.TargetInstanceProxy;
import org.jboss.weld.logging.BeanLogger;
import org.jboss.weld.security.GetDeclaredConstructorsAction;
import org.jboss.weld.security.GetDeclaredMethodsAction;
import org.jboss.weld.security.GetProtectionDomainAction;
import org.jboss.weld.security.NewInstanceAction;
import org.jboss.weld.serialization.spi.BeanIdentifier;
import org.jboss.weld.serialization.spi.ContextualStore;
import org.jboss.weld.serialization.spi.ProxyServices;
import org.jboss.weld.util.Proxies.TypeInfo;
import org.jboss.weld.util.bytecode.Boxing;
import org.jboss.weld.util.bytecode.BytecodeUtils;
import org.jboss.weld.util.bytecode.ClassFileUtils;
import org.jboss.weld.util.bytecode.ConstructorUtils;
import org.jboss.weld.util.bytecode.DeferredBytecode;
import org.jboss.weld.util.bytecode.DescriptorUtils;
import org.jboss.weld.util.bytecode.MethodInformation;
import org.jboss.weld.util.bytecode.RuntimeMethodInformation;
import org.jboss.weld.util.reflection.Reflections;
import org.jboss.weld.util.reflection.instantiation.InstantiatorFactory;
import com.google.common.collect.Sets;
/**
* Main factory to produce proxy classes and instances for Weld beans. This
* implementation creates proxies which forward non-static method invocations to
* a {@link BeanInstance}. All proxies implement the {@link Proxy} interface.
*
* @author David Allen
* @author Stuart Douglas
* @author Marius Bogoevici
* @author Ales Justin
*/
public class ProxyFactory<T> {
// Default proxy class name suffix
public static final String PROXY_SUFFIX = "$Proxy$";
public static final String DEFAULT_PROXY_PACKAGE = "org.jboss.weld.proxies";
private final Class<?> beanType;
private final Set<Class<?>> additionalInterfaces = new LinkedHashSet<Class<?>>();
private final ClassLoader classLoader;
private final String baseProxyName;
private final Bean<?> bean;
private final Class<?> proxiedBeanType;
private final String contextId;
public static final String CONSTRUCTED_FLAG_NAME = "constructed";
private final InstantiatorFactory instantiatorFactory;
protected static final BytecodeMethodResolver DEFAULT_METHOD_RESOLVER = new DefaultBytecodeMethodResolver();
protected static final String LJAVA_LANG_REFLECT_METHOD = "Ljava/lang/reflect/Method;";
protected static final String LJAVA_LANG_BYTE = "Ljava/lang/Byte;";
protected static final String LJAVA_LANG_CLASS = "Ljava/lang/Class;";
protected static final String LJAVA_LANG_OBJECT = "Ljava/lang/Object;";
protected static final String LBEAN_IDENTIFIER = "Lorg/jboss/weld/serialization/spi/BeanIdentifier;";
protected static final String LJAVA_LANG_STRING = "Ljava/lang/String;";
protected static final String LJAVA_LANG_THREAD_LOCAL = "Ljava/lang/ThreadLocal;";
protected static final String INIT_METHOD_NAME = "<init>";
protected static final String METHOD_HANDLER_FIELD_NAME = "methodHandler";
private static final String JAVA = "java";
private static final Set<ProxiedMethodFilter> METHOD_FILTERS;
static {
GroovyMethodFilter groovy = new GroovyMethodFilter();
if (groovy.isEnabled()) {
METHOD_FILTERS = Collections.<ProxiedMethodFilter>singleton(groovy);
} else {
METHOD_FILTERS = Collections.emptySet();
}
}
/**
* created a new proxy factory from a bean instance. The proxy name is
* generated from the bean id
*/
public ProxyFactory(String contextId, Class<?> proxiedBeanType, Set<? extends Type> typeClosure, Bean<?> bean) {
this(contextId, proxiedBeanType, typeClosure, bean, false);
}
public ProxyFactory(String contextId, Class<?> proxiedBeanType, Set<? extends Type> typeClosure, Bean<?> bean, boolean forceSuperClass) {
this(contextId, proxiedBeanType, typeClosure, getProxyName(contextId, proxiedBeanType, typeClosure, bean), bean, forceSuperClass);
}
/**
* Creates a new proxy factory when the name of the proxy class is already
* known, such as during de-serialization
*
* @param proxiedBeanType the super-class for this proxy class
* @param typeClosure the bean types of the bean
* @param proxyName the name of the proxy class
*/
public ProxyFactory(String contextId, Class<?> proxiedBeanType, Set<? extends Type> typeClosure, String proxyName, Bean<?> bean) {
this(contextId, proxiedBeanType, typeClosure, proxyName, bean, false);
}
public ProxyFactory(String contextId, Class<?> proxiedBeanType, Set<? extends Type> typeClosure, String proxyName, Bean<?> bean, boolean forceSuperClass) {
this.bean = bean;
this.contextId = contextId;
this.proxiedBeanType = proxiedBeanType;
addInterfacesFromTypeClosure(typeClosure, proxiedBeanType);
TypeInfo typeInfo = TypeInfo.of(typeClosure);
Class<?> superClass = typeInfo.getSuperClass();
superClass = superClass == null ? Object.class : superClass;
if (forceSuperClass || (superClass.equals(Object.class) && additionalInterfaces.isEmpty())) {
// No interface beans must use the bean impl as superclass
superClass = proxiedBeanType;
}
this.beanType = superClass;
addDefaultAdditionalInterfaces();
baseProxyName = proxyName;
if (bean != null) {
/*
* this may happen when creating an InjectionTarget for a decorator using BeanManager#createInjectionTarget()
* which does not allow the bean to be specified
*/
this.classLoader = resolveClassLoaderForBeanProxy(contextId, bean.getBeanClass(), typeInfo);
} else {
this.classLoader = resolveClassLoaderForBeanProxy(contextId, proxiedBeanType, typeInfo);
}
// hierarchy order
List<Class<?>> list = new ArrayList<Class<?>>(additionalInterfaces);
Collections.sort(list, ClassHierarchyComparator.INSTANCE);
additionalInterfaces.clear();
additionalInterfaces.addAll(list);
InstantiatorFactory factory = Container.instance(contextId).services().get(InstantiatorFactory.class);
if (factory != null && factory.useInstantiators() && isCreatingProxy()) {
this.instantiatorFactory = factory;
} else {
this.instantiatorFactory = null;
}
}
static String getProxyName(String contextId, Class<?> proxiedBeanType, Set<? extends Type> typeClosure, Bean<?> bean) {
TypeInfo typeInfo = TypeInfo.of(typeClosure);
String proxyPackage;
if (proxiedBeanType.equals(Object.class)) {
Class<?> superInterface = typeInfo.getSuperInterface();
if (superInterface == null) {
throw new IllegalArgumentException("Proxied bean type cannot be java.lang.Object without an interface");
} else {
proxyPackage = DEFAULT_PROXY_PACKAGE;
}
} else {
if (proxiedBeanType.getPackage() == null) {
proxyPackage = DEFAULT_PROXY_PACKAGE;
} else {
proxyPackage = proxiedBeanType.getPackage().getName();
}
}
final String className;
if (typeInfo.getSuperClass() == Object.class) {
final StringBuilder name = new StringBuilder();
//interface only bean.
className = createCompoundProxyName(contextId, bean, typeInfo, name) + PROXY_SUFFIX;
} else {
boolean typeModified = false;
for (Class<?> iface : typeInfo.getInterfaces()) {
if (!iface.isAssignableFrom(typeInfo.getSuperClass())) {
typeModified = true;
break;
}
}
if (typeModified) {
//this bean has interfaces that the base type is not assignable to
//which can happen with some creative use of the SPI
//interface only bean.
StringBuilder name = new StringBuilder(typeInfo.getSuperClass().getSimpleName() + "$");
className = createCompoundProxyName(contextId, bean, typeInfo, name) + PROXY_SUFFIX;
} else {
className = typeInfo.getSuperClass().getSimpleName() + PROXY_SUFFIX;
}
}
return proxyPackage + '.' + getEnclosingPrefix(proxiedBeanType) + className;
}
public void addInterfacesFromTypeClosure(Set<? extends Type> typeClosure, Class<?> proxiedBeanType) {
for (Type type : typeClosure) {
Class<?> c = Reflections.getRawType(type);
// Ignore no-interface views, they are dealt with proxiedBeanType
// (pending redesign)
if (c.isInterface()) {
addInterface(c);
}
}
}
private static String createCompoundProxyName(String contextId, Bean<?> bean, TypeInfo typeInfo, StringBuilder name) {
String className;
final List<String> interfaces = new ArrayList<String>();
for (Class<?> type : typeInfo.getInterfaces()) {
interfaces.add(type.getSimpleName());
}
Collections.sort(interfaces);
for (final String iface : interfaces) {
name.append(iface);
name.append('$');
}
//there is a remote chance that this could generate the same
//proxy name for two interfaces with the same simple name.
//append the hash code of the bean id to be sure
if (bean != null) {
final BeanIdentifier id = Container.instance(contextId).services().get(ContextualStore.class).putIfAbsent(bean);
int idHash = id.hashCode();
name.append(Math.abs(idHash == Integer.MIN_VALUE ? 0 : idHash));
}
className = name.toString();
return className;
}
private static String getEnclosingPrefix(Class<?> clazz) {
Class<?> encl = clazz.getEnclosingClass();
return encl == null ? "" : getEnclosingPrefix(encl) + encl.getSimpleName() + '$';
}
protected boolean isCreatingProxy() {
return true;
}
/**
* Adds an additional interface that the proxy should implement. The default
* implementation will be to forward invocations to the bean instance.
*
* @param newInterface an interface
*/
public void addInterface(Class<?> newInterface) {
if (!newInterface.isInterface()) {
throw new IllegalArgumentException(newInterface + " is not an interface");
}
additionalInterfaces.add(newInterface);
}
/**
* Method to create a new proxy that wraps the bean instance.
*
* @param beanInstance the bean instance
* @return a new proxy object
*/
public T create(BeanInstance beanInstance) {
T proxy;
Class<T> proxyClass = getProxyClass();
try {
if (instantiatorFactory != null) {
proxy = instantiatorFactory.getInstantiator().instantiate(proxyClass);
} else {
proxy = AccessController.doPrivileged(NewInstanceAction.of(proxyClass));
}
} catch (PrivilegedActionException e) {
if (e.getCause() instanceof InstantiationException) {
throw new DefinitionException(BeanLogger.LOG.proxyInstantiationFailed(this), e.getCause());
} else if (e.getCause() instanceof IllegalAccessException) {
throw new DefinitionException(BeanLogger.LOG.proxyInstantiationBeanAccessFailed(this), e.getCause());
} else {
throw new WeldException(e.getCause());
}
}
((ProxyObject) proxy).setHandler(new ProxyMethodHandler(contextId, beanInstance, bean));
return proxy;
}
/**
* Produces or returns the existing proxy class. The operation is thread-safe.
*
* @return always the class of the proxy
*/
public Class<T> getProxyClass() {
String suffix = "_$$_Weld" + getProxyNameSuffix();
String proxyClassName = getBaseProxyName();
if (!proxyClassName.endsWith(suffix)) {
proxyClassName = proxyClassName + suffix;
}
if (proxyClassName.startsWith(JAVA)) {
proxyClassName = proxyClassName.replaceFirst(JAVA, "org.jboss.weld");
}
Class<T> proxyClass = null;
BeanLogger.LOG.generatingProxyClass(proxyClassName);
try {
// First check to see if we already have this proxy class
proxyClass = cast(classLoader.loadClass(proxyClassName));
} catch (ClassNotFoundException e) {
// Create the proxy class for this instance
try {
proxyClass = createProxyClass(proxyClassName);
} catch (Throwable e1) {
//attempt to load the class again, just in case another thread
//defined it between the check and the create method
try {
proxyClass = cast(classLoader.loadClass(proxyClassName));
} catch (ClassNotFoundException e2) {
throw BeanLogger.LOG.unableToLoadProxyClass(bean, proxiedBeanType, classLoader, e1);
}
}
}
return proxyClass;
}
protected Class<T> getCachedProxyClass(String proxyClassName) {
try {
// Check to see if we already have this proxy class
return cast(classLoader.loadClass(proxyClassName));
} catch (ClassNotFoundException e) {
return null;
}
}
/**
* Returns the package and base name for the proxy class.
*
* @return base name without suffixes
*/
protected String getBaseProxyName() {
return baseProxyName;
}
/**
* Convenience method to determine if an object is a proxy generated by this
* factory or any derived factory.
*
* @param proxySuspect the object suspected of being a proxy
* @return true only if it is a proxy object
*/
public static boolean isProxy(Object proxySuspect) {
return proxySuspect instanceof ProxyObject;
}
/**
* Convenience method to set the underlying bean instance for a proxy.
*
* @param proxy the proxy instance
* @param beanInstance the instance of the bean
*/
public static <T> void setBeanInstance(String contextId, T proxy, BeanInstance beanInstance, Bean<?> bean) {
if (proxy instanceof ProxyObject) {
ProxyObject proxyView = (ProxyObject) proxy;
proxyView.setHandler(new ProxyMethodHandler(contextId, beanInstance, bean));
}
}
/**
* Returns a suffix to append to the name of the proxy class. The name
* already consists of <class-name>_$$_Weld, to which the suffix is added.
* This allows the creation of different types of proxies for the same class.
*
* @return a name suffix
*/
protected String getProxyNameSuffix() {
return PROXY_SUFFIX;
}
private void addDefaultAdditionalInterfaces() {
additionalInterfaces.add(Serializable.class);
}
/**
* Sub classes may override to specify additional interfaces the proxy should
* implement
*/
protected void addAdditionalInterfaces(Set<Class<?>> interfaces) {
}
private Class<T> createProxyClass(String proxyClassName) throws Exception {
Set<Class<?>> specialInterfaces = Sets.newHashSet(LifecycleMixin.class, TargetInstanceProxy.class, ProxyObject.class);
addAdditionalInterfaces(specialInterfaces);
// Remove special interfaces from main set (deserialization scenario)
additionalInterfaces.removeAll(specialInterfaces);
ClassFile proxyClassType = null;
if (getBeanType().isInterface()) {
proxyClassType = new ClassFile(proxyClassName, Object.class.getName());
proxyClassType.addInterface(getBeanType().getName());
} else {
proxyClassType = new ClassFile(proxyClassName, getBeanType().getName());
}
// Add interfaces which require method generation
for (Class<?> clazz : additionalInterfaces) {
proxyClassType.addInterface(clazz.getName());
}
List<DeferredBytecode> initialValueBytecode = new ArrayList<DeferredBytecode>();
ClassMethod staticConstructor = proxyClassType.addMethod(AccessFlag.PUBLIC, "<clinit>", "V");
addFields(proxyClassType, initialValueBytecode);
addConstructors(proxyClassType, initialValueBytecode);
addMethods(proxyClassType, staticConstructor);
staticConstructor.getCodeAttribute().returnInstruction();
// Additional interfaces whose methods require special handling
for (Class<?> specialInterface : specialInterfaces) {
proxyClassType.addInterface(specialInterface.getName());
}
// TODO: change the ProxyServices SPI to allow the container to figure out
// which PD to use
if (SystemPropertiesConfiguration.INSTANCE.isProxyDumpEnabled()) {
dumpToFile(SystemPropertiesConfiguration.INSTANCE.getProxyDumpPath(), proxyClassName, proxyClassType.toBytecode());
}
ProtectionDomain domain = AccessController.doPrivileged(new GetProtectionDomainAction(proxiedBeanType));
if (proxiedBeanType.getPackage() == null || proxiedBeanType.equals(Object.class)) {
domain = ProxyFactory.class.getProtectionDomain();
} else if (System.getSecurityManager() != null) {
ProtectionDomainCache cache = Container.instance(contextId).services().get(ProtectionDomainCache.class);
domain = cache.getProtectionDomainForProxy(domain);
}
Class<T> proxyClass = cast(ClassFileUtils.toClass(proxyClassType, classLoader, domain));
BeanLogger.LOG.createdProxyClass(proxyClass, Arrays.toString(proxyClass.getInterfaces()));
return proxyClass;
}
private void dumpToFile(File dumpPath, String fileName, byte[] data) {
File dumpFile = new File(dumpPath, fileName + ".class");
try {
Files.write(dumpFile.toPath(), data, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING);
} catch(IOException e) {
BeanLogger.LOG.beanCannotBeDumped(fileName, e);
}
}
/**
* Adds a constructor for the proxy for each constructor declared by the base
* bean type.
*
* @param proxyClassType the Javassist class for the proxy
* @param initialValueBytecode
*/
protected void addConstructors(ClassFile proxyClassType, List<DeferredBytecode> initialValueBytecode) {
try {
if (getBeanType().isInterface()) {
ConstructorUtils.addDefaultConstructor(proxyClassType, initialValueBytecode, isUsingUnsafeInstantiators());
} else {
boolean constructorFound = false;
for (Constructor<?> constructor : AccessController.doPrivileged(new GetDeclaredConstructorsAction(getBeanType()))) {
if ((constructor.getModifiers() & Modifier.PRIVATE) == 0) {
constructorFound = true;
String[] exceptions = new String[constructor.getExceptionTypes().length];
for (int i = 0; i < exceptions.length; ++i) {
exceptions[i] = constructor.getExceptionTypes()[i].getName();
}
ConstructorUtils.addConstructor(DescriptorUtils.VOID_CLASS_DESCRIPTOR, DescriptorUtils.getParameterTypes(constructor.getParameterTypes()), exceptions, proxyClassType, initialValueBytecode, isUsingUnsafeInstantiators());
}
}
if (!constructorFound) {
// the bean only has private constructors, we need to generate
// two fake constructors that call each other
addConstructorsForBeanWithPrivateConstructors(proxyClassType);
}
}
} catch (Exception e) {
throw new WeldException(e);
}
}
protected void addFields(ClassFile proxyClassType, List<DeferredBytecode> initialValueBytecode) {
// The field representing the underlying instance or special method
// handling
proxyClassType.addField(AccessFlag.PRIVATE, METHOD_HANDLER_FIELD_NAME, MethodHandler.class);
if(!isUsingUnsafeInstantiators()) {
// field used to indicate that super() has been called
proxyClassType.addField(AccessFlag.PRIVATE, CONSTRUCTED_FLAG_NAME, DescriptorUtils.BOOLEAN_CLASS_DESCRIPTOR);
}
}
protected void addMethods(ClassFile proxyClassType, ClassMethod staticConstructor) {
// Add all class methods for interception
addMethodsFromClass(proxyClassType, staticConstructor);
// Add special proxy methods
addSpecialMethods(proxyClassType, staticConstructor);
// Add serialization support methods
addSerializationSupport(proxyClassType);
}
/**
* Adds special serialization code. By default this is a nop
*
* @param proxyClassType the Javassist class for the proxy class
*/
protected void addSerializationSupport(ClassFile proxyClassType) {
//noop
}
protected void addMethodsFromClass(ClassFile proxyClassType, ClassMethod staticConstructor) {
try {
// Add all methods from the class hierarchy
Class<?> cls = getBeanType();
// first add equals/hashCode methods if required
generateEqualsMethod(proxyClassType);
generateHashCodeMethod(proxyClassType);
while (cls != null) {
for (Method method : AccessController.doPrivileged(new GetDeclaredMethodsAction(cls))) {
if (!Modifier.isStatic(method.getModifiers()) &&
!Modifier.isFinal(method.getModifiers()) &&
(method.getDeclaringClass() != Object.class || method.getName().equals("toString")) &&
isMethodAccepted(method)) {
try {
MethodInformation methodInfo = new RuntimeMethodInformation(method);
ClassMethod classMethod = proxyClassType.addMethod(method);
addConstructedGuardToMethodBody(classMethod);
createForwardingMethodBody(classMethod, methodInfo, staticConstructor);
BeanLogger.LOG.addingMethodToProxy(method);
} catch (DuplicateMemberException e) {
// do nothing. This will happen if superclass methods
// have been overridden
}
}
}
cls = cls.getSuperclass();
}
for (Class<?> c : additionalInterfaces) {
for (Method method : c.getMethods()) {
if (!Modifier.isStatic(method.getModifiers()) && isMethodAccepted(method)) {
try {
MethodInformation methodInfo = new RuntimeMethodInformation(method);
ClassMethod classMethod = proxyClassType.addMethod(method);
createSpecialMethodBody(classMethod, methodInfo, staticConstructor);
BeanLogger.LOG.addingMethodToProxy(method);
} catch (DuplicateMemberException e) {
}
}
}
}
} catch (Exception e) {
throw new WeldException(e);
}
}
private boolean isMethodAccepted(Method method) {
for (ProxiedMethodFilter filter : METHOD_FILTERS) {
if (!filter.accept(method)) {
return false;
}
}
return true;
}
/**
* Generate the body of the proxies hashCode method.
* <p/>
* If this method returns null, the method will not be added, and the
* hashCode on the superclass will be used as per normal virtual method
* resolution rules
*/
protected void generateHashCodeMethod(ClassFile proxyClassType) {
}
/**
* Generate the body of the proxies equals method.
* <p/>
* If this method returns null, the method will not be added, and the
* hashCode on the superclass will be used as per normal virtual method
* resolution rules
*
* @param proxyClassType The class file
*/
protected void generateEqualsMethod(ClassFile proxyClassType) {
}
protected void createSpecialMethodBody(ClassMethod proxyClassType, MethodInformation method, ClassMethod staticConstructor) {
createInterceptorBody(proxyClassType, method, staticConstructor);
}
/**
* Adds the following code to a delegating method:
* <p/>
* <code>
* if(!this.constructed) return super.thisMethod()
* </code>
* <p/>
* This means that the proxy will not start to delegate to the underlying
* bean instance until after the constructor has finished.
*/
protected void addConstructedGuardToMethodBody(final ClassMethod classMethod) {
if(isUsingUnsafeInstantiators()) {
return;
}
// now create the conditional
final CodeAttribute cond = classMethod.getCodeAttribute();
cond.aload(0);
cond.getfield(classMethod.getClassFile().getName(), CONSTRUCTED_FLAG_NAME, DescriptorUtils.BOOLEAN_CLASS_DESCRIPTOR);
// jump if the proxy constructor has finished
BranchEnd jumpMarker = cond.ifne();
// generate the invokespecial call to the super class method
// this is run when the proxy is being constructed
cond.aload(0);
cond.loadMethodParameters();
cond.invokespecial(classMethod.getClassFile().getSuperclass(), classMethod.getName(), classMethod.getDescriptor());
cond.returnInstruction();
cond.branchEnd(jumpMarker);
}
protected void createForwardingMethodBody(ClassMethod classMethod, MethodInformation method, ClassMethod staticConstructor) {
createInterceptorBody(classMethod, method, staticConstructor);
}
/**
* Creates the given method on the proxy class where the implementation
* forwards the call directly to the method handler.
* <p/>
* the generated bytecode is equivalent to:
* <p/>
* return (RetType) methodHandler.invoke(this,param1,param2);
*
* @param classMethod the class method
* @param method any JLR method
* @return the method byte code
*/
protected void createInterceptorBody(ClassMethod classMethod, MethodInformation method, ClassMethod staticConstructor) {
invokeMethodHandler(classMethod, method, true, DEFAULT_METHOD_RESOLVER, staticConstructor);
}
/**
* calls methodHandler.invoke for a given method
*
* @param method The method information
* @param addReturnInstruction set to true you want to return the result of
* the method invocation
* @param bytecodeMethodResolver The resolver that returns the method to invoke
*/
protected static void invokeMethodHandler(ClassMethod classMethod, MethodInformation method, boolean addReturnInstruction, BytecodeMethodResolver bytecodeMethodResolver, ClassMethod staticConstructor) {
// now we need to build the bytecode. The order we do this in is as
// follows:
// load methodHandler
// load this
// load the method object
// load null
// create a new array the same size as the number of parameters
// push our parameter values into the array
// invokeinterface the invoke method
// add checkcast to cast the result to the return type, or unbox if
// primitive
// add an appropriate return instruction
final CodeAttribute b = classMethod.getCodeAttribute();
b.aload(0);
b.getfield(classMethod.getClassFile().getName(), METHOD_HANDLER_FIELD_NAME, DescriptorUtils.classToStringRepresentation(MethodHandler.class));
b.aload(0);
bytecodeMethodResolver.getDeclaredMethod(classMethod, method.getDeclaringClass(), method.getName(), method.getParameterTypes(), staticConstructor);
b.aconstNull();
b.iconst(method.getParameterTypes().length);
b.anewarray("java.lang.Object");
int localVariableCount = 1;
for (int i = 0; i < method.getParameterTypes().length; ++i) {
String typeString = method.getParameterTypes()[i];
b.dup(); // duplicate the array reference
b.iconst(i);
// load the parameter value
BytecodeUtils.addLoadInstruction(b, typeString, localVariableCount);
// box the parameter if necessary
Boxing.boxIfNecessary(b, typeString);
// and store it in the array
b.aastore();
if (DescriptorUtils.isWide(typeString)) {
localVariableCount = localVariableCount + 2;
} else {
localVariableCount++;
}
}
// now we have all our arguments on the stack
// lets invoke the method
b.invokeinterface(MethodHandler.class.getName(), "invoke", LJAVA_LANG_OBJECT, new String[] { LJAVA_LANG_OBJECT,
LJAVA_LANG_REFLECT_METHOD, LJAVA_LANG_REFLECT_METHOD, "[" + LJAVA_LANG_OBJECT });
if (addReturnInstruction) {
// now we need to return the appropriate type
if (method.getReturnType().equals(DescriptorUtils.VOID_CLASS_DESCRIPTOR)) {
b.returnInstruction();
} else if(DescriptorUtils.isPrimitive(method.getReturnType())) {
Boxing.unbox(b, method.getReturnType());
b.returnInstruction();
} else {
String castType = method.getReturnType();
if (!method.getReturnType().startsWith("[")) {
castType = method.getReturnType().substring(1).substring(0, method.getReturnType().length() - 2);
}
b.checkcast(castType);
b.returnInstruction();
}
}
}
/**
* Adds methods requiring special implementations rather than just
* delegation.
*
* @param proxyClassType the Javassist class description for the proxy type
*/
protected void addSpecialMethods(ClassFile proxyClassType, ClassMethod staticConstructor) {
try {
// Add special methods for interceptors
for (Method method : LifecycleMixin.class.getMethods()) {
BeanLogger.LOG.addingMethodToProxy(method);
MethodInformation methodInfo = new RuntimeMethodInformation(method);
final ClassMethod classMethod = proxyClassType.addMethod(method);
createInterceptorBody(classMethod, methodInfo, staticConstructor);
}
Method getInstanceMethod = TargetInstanceProxy.class.getMethod("getTargetInstance");
Method getInstanceClassMethod = TargetInstanceProxy.class.getMethod("getTargetClass");
MethodInformation getInstanceMethodInfo = new RuntimeMethodInformation(getInstanceMethod);
createInterceptorBody(proxyClassType.addMethod(getInstanceMethod), getInstanceMethodInfo, staticConstructor);
MethodInformation getInstanceClassMethodInfo = new RuntimeMethodInformation(getInstanceClassMethod);
createInterceptorBody(proxyClassType.addMethod(getInstanceClassMethod), getInstanceClassMethodInfo, staticConstructor);
Method setMethodHandlerMethod = ProxyObject.class.getMethod("setHandler", MethodHandler.class);
generateSetMethodHandlerBody(proxyClassType.addMethod(setMethodHandlerMethod));
Method getMethodHandlerMethod = ProxyObject.class.getMethod("getHandler");
generateGetMethodHandlerBody(proxyClassType.addMethod(getMethodHandlerMethod));
} catch (Exception e) {
throw new WeldException(e);
}
}
private static void generateSetMethodHandlerBody(ClassMethod method) {
final CodeAttribute b = method.getCodeAttribute();
b.aload(0);
b.aload(1);
b.putfield(method.getClassFile().getName(), METHOD_HANDLER_FIELD_NAME, DescriptorUtils.classToStringRepresentation(MethodHandler.class));
b.returnInstruction();
}
private static void generateGetMethodHandlerBody(ClassMethod method) {
final CodeAttribute b = method.getCodeAttribute();
b.aload(0);
b.getfield(method.getClassFile().getName(), METHOD_HANDLER_FIELD_NAME, DescriptorUtils.classToStringRepresentation(MethodHandler.class));
b.returnInstruction();
}
/**
* Adds two constructors to the class that call each other in order to bypass
* the JVM class file verifier.
* <p/>
* This would result in a stack overflow if they were actually called,
* however the proxy is directly created without calling the constructor
*/
private void addConstructorsForBeanWithPrivateConstructors(ClassFile proxyClassType) {
ClassMethod ctor = proxyClassType.addMethod(AccessFlag.PUBLIC, INIT_METHOD_NAME, DescriptorUtils.VOID_CLASS_DESCRIPTOR, LJAVA_LANG_BYTE);
CodeAttribute b = ctor.getCodeAttribute();
b.aload(0);
b.aconstNull();
b.aconstNull();
b.invokespecial(proxyClassType.getName(), INIT_METHOD_NAME, "(" + LJAVA_LANG_BYTE + LJAVA_LANG_BYTE + ")" + DescriptorUtils.VOID_CLASS_DESCRIPTOR);
b.returnInstruction();
ctor = proxyClassType.addMethod(AccessFlag.PUBLIC, INIT_METHOD_NAME, DescriptorUtils.VOID_CLASS_DESCRIPTOR, LJAVA_LANG_BYTE, LJAVA_LANG_BYTE);
b = ctor.getCodeAttribute();
b.aload(0);
b.aconstNull();
b.invokespecial(proxyClassType.getName(), INIT_METHOD_NAME, "(" + LJAVA_LANG_BYTE + ")" + DescriptorUtils.VOID_CLASS_DESCRIPTOR);
b.returnInstruction();
}
public Class<?> getBeanType() {
return beanType;
}
public Set<Class<?>> getAdditionalInterfaces() {
return additionalInterfaces;
}
public Bean<?> getBean() {
return bean;
}
public String getContextId() {
return contextId;
}
/**
* Figures out the correct class loader to use for a proxy for a given bean
*/
public static ClassLoader resolveClassLoaderForBeanProxy(String contextId, Class<?> proxiedType, TypeInfo typeInfo) {
Class<?> superClass = typeInfo.getSuperClass();
if (superClass.getName().startsWith(JAVA)) {
ClassLoader cl = Container.instance(contextId).services().get(ProxyServices.class).getClassLoader(proxiedType);
if (cl == null) {
cl = Thread.currentThread().getContextClassLoader();
}
return cl;
}
return Container.instance(contextId).services().get(ProxyServices.class).getClassLoader(superClass);
}
protected boolean isUsingUnsafeInstantiators() {
return instantiatorFactory != null;
}
}