cglib 源代码分析（原创）
2016-02-25 18:33
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最近读了下cglib 的源代码,分析了cglib 通过字节码生成的代理类。就用cglib源代码包中的例子吧.
1.首先eclipse中开启debug模式,如图
例子的代码如下
public static void main(String args[]) {
Bean bean = (Bean)newInstance(Bean.class);
bean.addPropertyChangeListener(
new PropertyChangeListener() {
public void propertyChange(PropertyChangeEvent evt) {
}
}
);
bean.setSampleProperty("TEST");
}
转入newInstance方法中
public static Object newInstance(Class clazz) {
try {
Beans interceptor = new Beans();
Enhancer e = new Enhancer();
e.setSuperclass(clazz);
e.setCallback(interceptor);
Object bean = e.create();
interceptor.propertySupport = new PropertyChangeSupport(bean);
return bean;
} catch (Throwable e) {
e.printStackTrace();
throw new Error(e.getMessage());
}
}
Enhancer 类中主要的几个配置参数,也是cglib代理的几个配置参数
( 1 )
private Class[] interfaces; private CallbackFilter filter; private Callback[] callbacks; private Type[] callbackTypes; private boolean classOnly; private Class superclass; private Class[] argumentTypes; private Object[] arguments; private boolean useFactory = true; private Long serialVersionUID; private boolean interceptDuringConstruction = true;
在Enhancer类中有个KEY_FACTORY的属性
private static final EnhancerKey KEY_FACTORY = (EnhancerKey) KeyFactory.create(EnhancerKey.class);
此行代码会自动生成 Enhancer 类的 内部接口 EnhancerKey 的实现类
public interface EnhancerKey {
public Object newInstance( String type, String[] interfaces, CallbackFilter filter, Type[] callbackTypes, boolean useFactory, boolean interceptDuringConstruction, Long serialVersionUID );
}
反编译.class 文件的内容如下, 备注: 有些代码无法反编译,我参照.asm文件 重新改写了一下
package net.sf.cglib.proxy;
import net.sf.cglib.core.KeyFactory;
import org.objectweb.asm.Type;
public class Enhancer$EnhancerKey$$KeyFactoryByCGLIB$$7fb24d72 extends KeyFactory implements Enhancer.EnhancerKey {
private final String FIELD_0;
private final String[] FIELD_1;
private final CallbackFilter FIELD_2;
private final Type[] FIELD_3;
private final boolean FIELD_4;
private final boolean FIELD_5;
private final Long FIELD_6;
public Enhancer$EnhancerKey$$KeyFactoryByCGLIB$$7fb24d72() {
/** 以下在字节码指令中并没用赋值, 如果不赋值的话在eclipse的编译器中会报错,可能是final 字段在编译级别做了限制,在Jvm的指令中并没有啥实质的作用.*/
this.FIELD_0 = null;
this.FIELD_1 = null;
this.FIELD_2 = null;
this.FIELD_3 = null;
this.FIELD_4 = false;
this.FIELD_5 = false;
this.FIELD_6 = 0L;
}
public Object newInstance(String paramString, String[] paramArrayOfString, CallbackFilter paramCallbackFilter, Type[] paramArrayOfType, boolean paramBoolean1, boolean paramBoolean2, Long paramLong) {
return new Enhancer$EnhancerKey$$KeyFactoryByCGLIB$$7fb24d72(paramString, paramArrayOfString, paramCallbackFilter, paramArrayOfType, paramBoolean1, paramBoolean2, paramLong);
}
public Enhancer$EnhancerKey$$KeyFactoryByCGLIB$$7fb24d72(String paramString, String[] paramArrayOfString, CallbackFilter paramCallbackFilter, Type[] paramArrayOfType, boolean paramBoolean1, boolean paramBoolean2, Long paramLong) {
this.FIELD_0 = paramString;
this.FIELD_1 = paramArrayOfString;
this.FIELD_2 = paramCallbackFilter;
this.FIELD_3 = paramArrayOfType;
this.FIELD_4 = paramBoolean1;
this.FIELD_5 = paramBoolean2;
this.FIELD_6 = paramLong;
}
public int hashCode() {
// 根据 KeyFactory类的 PRIMES数组得来的
int result = 8095873;
result += (FIELD_0 != null ? FIELD_0.hashCode() * 69403 : 0);
if(FIELD_1 != null) {
if(FIELD_1.length > 0) {
String s0 = FIELD_1[0];
result += (s0.hashCode() * 69403);
}
}
result += (FIELD_2 != null ? FIELD_2.hashCode() * 69403 : 0);
if(FIELD_3 != null) {
if(FIELD_3.length > 0) {
Type t0 = FIELD_3[0];
result += t0.hashCode() * 69403;
}
}
result += FIELD_4 ? 1 : 0;
result += FIELD_5 ? 1 : 0;
result += FIELD_6.hashCode() * 69403;
return result;
}
public boolean equals(Object paramObject) {
// 略
}
public String toString() {
// 略
}
}
在回到 Object bean = e.create();这行代码 , 之后会转到这
private Object createHelper() {
validate();
if (superclass != null) {
setNamePrefix(superclass.getName());
} else if (interfaces != null) {
setNamePrefix(interfaces[ReflectUtils.findPackageProtected(interfaces)].getName());
}
return super.create(KEY_FACTORY.newInstance((superclass != null) ? superclass.getName() : null, ReflectUtils.getNames(interfaces), filter, callbackTypes, useFactory, interceptDuringConstruction, serialVersionUID));
}
KEY_FACTORY.newInstance 这创建一个 Enhancer$EnhancerKey$$KeyFactoryByCGLIB$$7fb24d72 这个对象的实例,
主要是作用是存储Enhancer 类的几个参数 上面 ( 1 )
之后转到 AbstractClassGenerator 类的create方法 如下代码
protected Object create(Object key) {
try {
Class gen = null;
synchronized (source) {
ClassLoader loader = getClassLoader();
ProtectionDomain protectionDomain = getProtectionDomain();
Map cache2 = null;
cache2 = (Map) source.cache.get(loader);
if (cache2 == null) {
cache2 = new HashMap();
cache2.put(NAME_KEY, new HashSet());
source.cache.put(loader, cache2);
} else if (useCache) {
Reference ref = (Reference) cache2.get(key);
gen = (Class) ((ref == null) ? null : ref.get());
}
if (gen == null) {
Object save = CURRENT.get();
CURRENT.set(this);
try {
this.key = key;
if (attemptLoad) {
try {
gen = loader.loadClass(getClassName());
} catch (ClassNotFoundException e) {
// ignore
}
}
if (gen == null) {
byte[] b = strategy.generate(this);
String className = ClassNameReader.getClassName(new ClassReader(b));
getClassNameCache(loader).add(className);
if (protectionDomain == null) {
gen = ReflectUtils.defineClass(className, b, loader);
} else {
gen = ReflectUtils.defineClass(className, b, loader, protectionDomain);
}
}
if (useCache) {
cache2.put(key, new WeakReference(gen));
}
return firstInstance(gen);
} finally {
CURRENT.set(save);
}
}
}
return firstInstance(gen);
} catch (RuntimeException e) {
throw e;
} catch (Error e) {
throw e;
} catch (Exception e) {
throw new CodeGenerationException(e);
}
}
标红的代码 byte[] b = strategy.generate(this); 最终会转到 Enhancer 类的 generateClass方法 是创建代理的主要方法, 具体代码如下
public void generateClass(ClassVisitor v) throws Exception {
// superclass 是要代理的类
Class sc = (superclass == null) ? Object.class : superclass;
// 如果是 final 修饰的方法 抛出异常
if (TypeUtils.isFinal(sc.getModifiers()))
throw new IllegalArgumentException("Cannot subclass final class " + sc.getName());
// 构造方法
List constructors = new ArrayList(Arrays.asList(sc.getDeclaredConstructors()));
20000
filterConstructors(sc, constructors);
// Order is very important: must add superclass, then its superclass chain, then each interface and its superinterfaces.
List actualMethods = new ArrayList();
List interfaceMethods = new ArrayList();
final Set forcePublic = new HashSet();
// 获取代理类的所有方法 和 代理类所实现接口的所有方法
getMethods(sc, interfaces, actualMethods, interfaceMethods, forcePublic);
List methods = CollectionUtils.transform(actualMethods,
new Transformer() {
public Object transform(Object value) {
Method method = (Method) value;
int modifiers = Constants.ACC_FINAL | (method.getModifiers( ) & ~Constants.ACC_ABSTRACT & ~Constants.ACC_NATIVE & ~Constants.ACC_SYNCHRONIZED);
if (forcePublic.contains(MethodWrapper.create(method))) {
modifiers = (modifiers & ~Constants.ACC_PROTECTED) | Constants.ACC_PUBLIC;
}
return ReflectUtils.getMethodInfo(method, modifiers);
}
}
);
// 以下是asm操作字节码
ClassEmitter e = new ClassEmitter(v);
// useFactory => true
// net.sf.cglib.samples.Bean$$EnhancerByCGLIB$$a7ee9d2a
e.begin_class( Constants.V1_2, Constants.ACC_PUBLIC, getClassName(), Type.getType(sc), (useFactory ? TypeUtils.add(TypeUtils.getTypes(interfaces), FACTORY) : TypeUtils.getTypes(interfaces)), Constants.SOURCE_FILE );
// [<init>()V]
List constructorInfo = CollectionUtils.transform(constructors, MethodInfoTransformer.getInstance());
e.declare_field(Constants.ACC_PRIVATE, BOUND_FIELD, Type.BOOLEAN_TYPE, null);
// interceptDuringConstruction => true
if (!interceptDuringConstruction) {
e.declare_field(Constants.ACC_PRIVATE, CONSTRUCTED_FIELD, Type.BOOLEAN_TYPE, null);
}
e.declare_field(Constants.PRIVATE_FINAL_STATIC, THREAD_CALLBACKS_FIELD, THREAD_LOCAL, null);
e.declare_field(Constants.PRIVATE_FINAL_STATIC, STATIC_CALLBACKS_FIELD, CALLBACK_ARRAY, null);
if (serialVersionUID != null) {
e.declare_field(Constants.PRIVATE_FINAL_STATIC, Constants.SUID_FIELD_NAME, Type.LONG_TYPE, serialVersionUID);
}
for (int i = 0; i < callbackTypes.length; i++) {
e.declare_field(Constants.ACC_PRIVATE, getCallbackField(i), callbackTypes[i], null);
}
emitMethods(e, methods, actualMethods);
emitConstructors(e, constructorInfo);
emitSetThreadCallbacks(e);
emitSetStaticCallbacks(e);
emitBindCallbacks(e);
if (useFactory) {
int[] keys = getCallbackKeys();
emitNewInstanceCallbacks(e);
emitNewInstanceCallback(e);
emitNewInstanceMultiarg(e, constructorInfo);
emitGetCallback(e, keys);
emitSetCallback(e, keys);
emitGetCallbacks(e);
emitSetCallbacks(e);
}
e.end_class();
}
主要 是获取代理类的所有方法 和 代理类所实现接口的所有方法 用字节码将 所有的方法写到一个代理的类中,
具体生成的class文件反编译之后如下:
Bean$$EnhancerByCGLIB$$f51d20a3
package net.sf.cglib.samples;
import java.beans.PropertyChangeListener;
import java.lang.reflect.Method;
import org.apache.tools.ant.taskdefs.Get;
import net.sf.cglib.core.ReflectUtils;
import net.sf.cglib.core.Signature;
import net.sf.cglib.proxy.Callback;
import net.sf.cglib.proxy.Factory;
import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;
public class Bean$$EnhancerByCGLIB$$f51d20a3 extends Bean implements Factory {
private boolean CGLIB$BOUND;
private static final ThreadLocal CGLIB$THREAD_CALLBACKS;
private static /** final */Callback[] CGLIB$STATIC_CALLBACKS;
private MethodInterceptor CGLIB$CALLBACK_0;
private static final Method CGLIB$toString$0$Method;
private static final MethodProxy CGLIB$toString$0$Proxy;
private static final Object[] CGLIB$emptyArgs;
private static final Method CGLIB$setSampleProperty$1$Method;
private static final MethodProxy CGLIB$setSampleProperty$1$Proxy;
private static final Method CGLIB$getSampleProperty$2$Method;
private static final MethodProxy CGLIB$getSampleProperty$2$Proxy;
private static final Method CGLIB$addPropertyChangeListener$3$Method;
private static final MethodProxy CGLIB$addPropertyChangeListener$3$Proxy;
private static final Method CGLIB$removePropertyChangeListener$4$Method;
private static final MethodProxy CGLIB$removePropertyChangeListener$4$Proxy;
private static final Method CGLIB$finalize$5$Method;
private static final MethodProxy CGLIB$finalize$5$Proxy;
private static final Method CGLIB$equals$6$Method;
private static final MethodProxy CGLIB$equals$6$Proxy;
private static final Method CGLIB$hashCode$7$Method;
private static final MethodProxy CGLIB$hashCode$7$Proxy;
private static final Method CGLIB$clone$8$Method;
private static final MethodProxy CGLIB$clone$8$Proxy;
static {
// CGLIB$STATICHOOK1();
CGLIB$THREAD_CALLBACKS = new ThreadLocal();
CGLIB$emptyArgs = new Object[0];
Class localClass1 = null;
try {
localClass1 = Class.forName("net.sf.cglib.samples.Bean$$EnhancerByCGLIB$$f51d20a3");
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
Class localClass2 = null;
Method[] tmp83_80 = null;
try {
tmp83_80 = ReflectUtils.findMethods(new String[] { "finalize", "()V", "equals", "(Ljava/lang/Object;)Z", "hashCode", "()I", "clone", "()Ljava/lang/Object;" }, (localClass2 = Class.forName("java.lang.Object")).getDeclaredMethods());
} catch (SecurityException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} catch (ClassNotFoundException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
CGLIB$finalize$5$Method = tmp83_80[0];
CGLIB$finalize$5$Proxy = MethodProxy.create(localClass2, localClass1, "()V", "finalize", "CGLIB$finalize$5");
Method[] tmp103_83 = tmp83_80;
CGLIB$equals$6$Method = tmp103_83[1];
CGLIB$equals$6$Proxy = MethodProxy.create(localClass2, localClass1, "(Ljava/lang/Object;)Z", "equals", "CGLIB$equals$6");
Method[] tmp123_103 = tmp103_83;
CGLIB$hashCode$7$Method = tmp123_103[2];
CGLIB$hashCode$7$Proxy = MethodProxy.create(localClass2, localClass1, "()I", "hashCode", "CGLIB$hashCode$7");
Method[] tmp143_123 = tmp123_103;
CGLIB$clone$8$Method = tmp143_123[3];
CGLIB$clone$8$Proxy = MethodProxy.create(localClass2, localClass1, "()Ljava/lang/Object;", "clone", "CGLIB$clone$8");
try {
localClass2 = Class.forName("net.sf.cglib.samples.Bean");
} catch (ClassNotFoundException e) {
}
// tmp143_123;
Method[] tmp236_233 = ReflectUtils.findMethods(new String[] {
"toString",
"()Ljava/lang/String;",
"setSampleProperty",
"(Ljava/lang/String;)V",
"getSampleProperty",
"()Ljava/lang/String;",
"addPropertyChangeListener",
"(Ljava/beans/PropertyChangeListener;)V",
"removePropertyChangeListener",
"(Ljava/beans/PropertyChangeListener;)V"
},
localClass2.getDeclaredMethods()
);
CGLIB$toString$0$Method = tmp236_233[0];
CGLIB$toString$0$Proxy = MethodProxy.create(localClass2, localClass1, "()Ljava/lang/String;", "toString", "CGLIB$toString$0");
Method[] tmp256_236 = tmp236_233;
CGLIB$setSampleProperty$1$Method = tmp256_236[1];
CGLIB$setSampleProperty$1$Proxy = MethodProxy.create(localClass2, localClass1, "(Ljava/lang/String;)V", "setSampleProperty", "CGLIB$setSampleProperty$1");
Method[] tmp276_256 = tmp256_236;
CGLIB$getSampleProperty$2$Method = tmp276_256[2];
CGLIB$getSampleProperty$2$Proxy = MethodProxy.create(localClass2, localClass1, "()Ljava/lang/String;", "getSampleProperty", "CGLIB$getSampleProperty$2");
Method[] tmp296_276 = tmp276_256;
CGLIB$addPropertyChangeListener$3$Method = tmp296_276[3];
CGLIB$addPropertyChangeListener$3$Proxy = MethodProxy.create(localClass2, localClass1, "(Ljava/beans/PropertyChangeListener;)V", "addPropertyChangeListener", "CGLIB$addPropertyChangeListener$3");
Method[] tmp316_296 = tmp296_276;
CGLIB$removePropertyChangeListener$4$Method = tmp316_296[4];
CGLIB$removePropertyChangeListener$4$Proxy = MethodProxy.create(localClass2, localClass1, "(Ljava/beans/PropertyChangeListener;)V", "removePropertyChangeListener", "CGLIB$removePropertyChangeListener$4");
// tmp316_296;
}
static void CGLIB$STATICHOOK1() {
}
final String CGLIB$toString$0() {
return super.toString();
}
public final String toString() {
MethodInterceptor tmp4_1 = this.CGLIB$CALLBACK_0;
if (tmp4_1 == null) {
CGLIB$BIND_CALLBACKS(this);
}
MethodInterceptor tmp17_14 = this.CGLIB$CALLBACK_0;
if (tmp17_14 != null) {
try {
return (String)tmp17_14.intercept(this, CGLIB$toString$0$Method, CGLIB$emptyArgs, CGLIB$toString$0$Proxy);
} catch (Throwable e) {
}
}
return super.toString();
}
final void CGLIB$setSampleProperty$1(String paramString) {
super.setSampleProperty(paramString);
}
public final void setSampleProperty(String paramString) {
MethodInterceptor tmp4_1 = this.CGLIB$CALLBACK_0;
if (tmp4_1 == null) {
CGLIB$BIND_CALLBACKS(this);
}
if (this.CGLIB$CALLBACK_0 != null) {
try {
tmp4_1.intercept(this, CGLIB$setSampleProperty$1$Method, new Object[] {paramString}, CGLIB$setSampleProperty$1$Proxy);
return;
} catch (Throwable e) {
}
}
super.setSampleProperty(paramString);
}
// CGLIB$emptyArgs
final String CGLIB$getSampleProperty$2() {
return super.getSampleProperty();
}
public final String getSampleProperty() {
MethodInterceptor tmp4_1 = this.CGLIB$CALLBACK_0;
if (tmp4_1 == null) {
CGLIB$BIND_CALLBACKS(this);
}
MethodInterceptor tmp17_14 = this.CGLIB$CALLBACK_0;
if (tmp17_14 != null) {
try {
return (String)tmp17_14.intercept(this, CGLIB$getSampleProperty$2$Method, CGLIB$emptyArgs, CGLIB$getSampleProperty$2$Proxy);
} catch (Throwable e) {
e.printStackTrace();
}
}
return super.getSampleProperty();
}
final void CGLIB$addPropertyChangeListener$3(PropertyChangeListener paramPropertyChangeListener) {
// compile error! superClass is abstract
// super.addPropertyChangeListener(paramPropertyChangeListener);
}
public final void addPropertyChangeListener(PropertyChangeListener paramPropertyChangeListener) {
MethodInterceptor tmp4_1 = this.CGLIB$CALLBACK_0;
if (tmp4_1 == null) {
// tmp4_1;
CGLIB$BIND_CALLBACKS(this);
}
if (this.CGLIB$CALLBACK_0 != null) {
try {
tmp4_1.intercept(this, CGLIB$addPropertyChangeListener$3$Method, new Object[]{paramPropertyChangeListener}, CGLIB$addPropertyChangeListener$3$Proxy);
return;
} catch (Throwable e) {
}
}
// compile error! superClass is abstract
// super.addPropertyChangeListener(paramPropertyChangeListener);
}
final void CGLIB$removePropertyChangeListener$4(PropertyChangeListener paramPropertyChangeListener) {
// compile error! superClass is abstract
// super.removePropertyChangeListener(paramPropertyChangeListener);
}
public final void removePropertyChangeListener(PropertyChangeListener paramPropertyChangeListener) {
MethodInterceptor tmp4_1 = this.CGLIB$CALLBACK_0;
if (tmp4_1 == null) {
// tmp4_1;
CGLIB$BIND_CALLBACKS(this);
}
if (this.CGLIB$CALLBACK_0 != null) {
try {
tmp4_1.intercept(this, CGLIB$removePropertyChangeListener$4$Method, new Object[]{paramPropertyChangeListener}, CGLIB$removePropertyChangeListener$4$Proxy);
return;
} catch (Throwable e) {
}
}
// super.removePropertyChangeListener(paramPropertyChangeListener);
}
final void CGLIB$finalize$5() throws Throwable {
super.finalize();
}
protected final void finalize() throws Throwable {
MethodInterceptor tmp4_1 = this.CGLIB$CALLBACK_0;
if (tmp4_1 == null) {
CGLIB$BIND_CALLBACKS(this);
}
if (this.CGLIB$CALLBACK_0 != null) {
tmp4_1.intercept(this, CGLIB$finalize$5$Method, CGLIB$emptyArgs, CGLIB$finalize$5$Proxy);
return;
}
super.finalize();
}
final boolean CGLIB$equals$6(Object paramObject) {
return super.equals(paramObject);
}
public final boolean equals(Object paramObject) {
MethodInterceptor tmp4_1 = this.CGLIB$CALLBACK_0;
if (tmp4_1 == null) {
// tmp4_1;
CGLIB$BIND_CALLBACKS(this);
}
MethodInterceptor tmp17_14 = this.CGLIB$CALLBACK_0;
if (tmp17_14 != null) {
Object tmp41_36;
try {
tmp41_36 = tmp17_14.intercept(this, CGLIB$equals$6$Method, new Object[] { paramObject }, CGLIB$equals$6$Proxy);
return tmp41_36 == null ? false : ((Boolean)tmp41_36).booleanValue();
} catch (Throwable e) {
e.printStackTrace();
}
}
return super.equals(paramObject);
}
final int CGLIB$hashCode$7() {
return super.hashCode();
}
public final int hashCode() {
MethodInterceptor tmp4_1 = this.CGLIB$CALLBACK_0;
if (tmp4_1 == null) {
CGLIB$BIND_CALLBACKS(this);
}
MethodInterceptor tmp17_14 = this.CGLIB$CALLBACK_0;
if (tmp17_14 != null) {
Object tmp36_31;
try {
tmp36_31 = tmp17_14.intercept(this, CGLIB$hashCode$7$Method, CGLIB$emptyArgs, CGLIB$hashCode$7$Proxy);
return tmp36_31 == null ? 0 : ((Number)tmp36_31).intValue();
} catch (Throwable e) {
}
}
return super.hashCode();
}
final Object CGLIB$clone$8() throws CloneNotSupportedException {
return super.clone();
}
protected final Object clone() throws CloneNotSupportedException {
MethodInterceptor tmp4_1 = this.CGLIB$CALLBACK_0;
if (tmp4_1 == null) {
CGLIB$BIND_CALLBACKS(this);
}
MethodInterceptor tmp17_14 = this.CGLIB$CALLBACK_0;
if (tmp17_14 != null) {
try {
return tmp17_14.intercept(this, CGLIB$clone$8$Method, CGLIB$emptyArgs, CGLIB$clone$8$Proxy);
} catch (Throwable e) {
// e.printStackTrace();
return null;
}
}
return super.clone();
}
public static MethodProxy CGLIB$findMethodProxy(Signature paramSignature) {
String tmp4_1 = paramSignature.toString();
switch (tmp4_1.hashCode()) {
case -1574182249:
if (tmp4_1.equals("finalize()V"))
return CGLIB$finalize$5$Proxy;
break;
case -1148146316:
if(tmp4_1.equals("addPropertyChangeListener(Ljava/beans/PropertyChangeListener;)V"))
return CGLIB$addPropertyChangeListener$3$Proxy;
case -727109664:
if(tmp4_1.equals("getSampleProperty()Ljava/lang/String;"))
return CGLIB$getSampleProperty$2$Proxy;
case -508378822:
if(tmp4_1.equals("clone()Ljava/lang/Object;"))
return CGLIB$clone$8$Proxy;
case -182669826:
if(tmp4_1.equals("setSampleProperty(Ljava/lang/String;)V"))
return CGLIB$setSampleProperty$1$Proxy;
case -112787753:
if(tmp4_1.equals("removePropertyChangeListener(Ljava/beans/PropertyChangeListener;)V"))
return CGLIB$removePropertyChangeListener$4$Proxy;
case 1826985398:
if(tmp4_1.equals("equals(Ljava/lang/Object;)Z"))
return CGLIB$equals$6$Proxy;
case 1913648695:
if(tmp4_1.equals("toString()Ljava/lang/String;"))
return CGLIB$toString$0$Proxy;
case 1984935277:
if(tmp4_1.equals("hashCode()I"))
return CGLIB$hashCode$7$Proxy;
default:
return CGLIB$finalize$5$Proxy;
}
return null;
}
public Bean$$EnhancerByCGLIB$$f51d20a3() {
CGLIB$BIND_CALLBACKS(this);
}
public static void CGLIB$SET_THREAD_CALLBACKS(Callback[] paramArrayOfCallback) {
CGLIB$THREAD_CALLBACKS.set(paramArrayOfCallback);
}
public static void CGLIB$SET_STATIC_CALLBACKS(Callback[] paramArrayOfCallback) {
CGLIB$STATIC_CALLBACKS = paramArrayOfCallback;
}
private static final void CGLIB$BIND_CALLBACKS(Object paramObject) {
if(paramObject instanceof Bean$$EnhancerByCGLIB$$f51d20a3) {
Bean$$EnhancerByCGLIB$$f51d20a3 f51d20a3 = (Bean$$EnhancerByCGLIB$$f51d20a3)paramObject;
if(f51d20a3.CGLIB$BOUND) {
return;
}
f51d20a3.CGLIB$BOUND = true;
Object obj = CGLIB$THREAD_CALLBACKS.get();
if(obj != null) {
Callback[] callbacks = (Callback[])obj;
MethodInterceptor interceptor = (MethodInterceptor)callbacks[0];
f51d20a3.CGLIB$CALLBACK_0 = interceptor;
return;
}
if(CGLIB$STATIC_CALLBACKS != null)
f51d20a3.CGLIB$CALLBACK_0 = (MethodInterceptor)CGLIB$STATIC_CALLBACKS[0];
}
}
public Object newInstance(Callback[] paramArrayOfCallback) {
CGLIB$SET_THREAD_CALLBACKS(paramArrayOfCallback);
Bean$$EnhancerByCGLIB$$f51d20a3 f51d20a3 = new Bean$$EnhancerByCGLIB$$f51d20a3();
CGLIB$SET_THREAD_CALLBACKS(null);
return f51d20a3;
}
public Object newInstance(Callback paramCallback) {
CGLIB$SET_THREAD_CALLBACKS(new Callback[] { paramCallback });
Bean$$EnhancerByCGLIB$$f51d20a3 f51d20a3 = new Bean$$EnhancerByCGLIB$$f51d20a3();
CGLIB$SET_THREAD_CALLBACKS(null);
return f51d20a3;
}
public Object newInstance(Class[] paramArrayOfClass, Object[] paramArrayOfObject, Callback[] paramArrayOfCallback) {
CGLIB$SET_THREAD_CALLBACKS(paramArrayOfCallback);
Class[] tmp9_8 = paramArrayOfClass;
Bean$$EnhancerByCGLIB$$f51d20a3 f51d20a3 = null;
switch (tmp9_8.length) {
case 0:
f51d20a3 = new Bean$$EnhancerByCGLIB$$f51d20a3();
break;
default:
throw new IllegalArgumentException("Constructor not found");
}
CGLIB$SET_THREAD_CALLBACKS(null);
return f51d20a3;
}
public Callback getCallback(int paramInt) {
CGLIB$BIND_CALLBACKS(this);
switch (paramInt) {
case 0:
break;
}
return null;
}
public void setCallback(int paramInt, Callback paramCallback) {
switch (paramInt) {
case 0:
this.CGLIB$CALLBACK_0 = ((MethodInterceptor) paramCallback);
break;
}
}
public Callback[] getCallbacks() {
CGLIB$BIND_CALLBACKS(this);
return new Callback[] { this.CGLIB$CALLBACK_0 };
}
public void setCallbacks(Callback[] paramArrayOfCallback) {
this.CGLIB$CALLBACK_0 = ((MethodInterceptor) paramArrayOfCallback[0]);
}
}
再回到 AbstractClassGenerator 类中 的create 方法中 ,最后有个 firstInstance方法的调用
protected Object firstInstance(Class type) throws Exception {
if (classOnly) {
return type;
} else {
return createUsingReflection(type);
}
}
看 createUsingReflection 方法
private Object createUsingReflection(Class type) {
setThreadCallbacks(type, callbacks);
try {
if (argumentTypes != null) {
return ReflectUtils.newInstance(type, argumentTypes, arguments);
} else {
return ReflectUtils.newInstance(type);
}
} finally {
// clear thread callbacks to allow them to be gc'd
setThreadCallbacks(type, null);
}
}
再看 setThreadCallbacks(type, callbacks);
private static void setThreadCallbacks(Class type, Callback[] callbacks) {
setCallbacksHelper(type, callbacks, SET_THREAD_CALLBACKS_NAME);// CGLIB$SET_THREAD_CALLBACKS
}
private static void setCallbacksHelper(Class type, Callback[] callbacks, String methodName) {
// TODO: optimize
try {
Method setter = getCallbacksSetter(type, methodName);
setter.invoke(null, new Object[] { callbacks });
} catch (NoSuchMethodException e) {
throw new IllegalArgumentException(type + " is not an enhanced class");
} catch (IllegalAccessException e) {
throw new CodeGenerationException(e);
} catch (InvocationTargetException e) {
throw new CodeGenerationException(e);
}
}
主要是反射 Bean$$EnhancerByCGLIB$$f51d20a3 类 中 的静态CGLIB$SET_THREAD_CALLBACKS方法
public static void CGLIB$SET_THREAD_CALLBACKS(Callback[] paramArrayOfCallback) {
CGLIB$THREAD_CALLBACKS.set(paramArrayOfCallback);
}
将 MethodInterceptor 接口的实现类 注入到ThreadLocal 中, 主要作用是 代理类在 进行实际调用方法之前先调用 MethodInterceptor 接口的intercept方法, 本例子中就是 Beans 类,
public class Beans implements MethodInterceptor
接下来 是通过反射设立一个 Bean$$EnhancerByCGLIB$$f51d20a3 对象, 查看 Bean$$EnhancerByCGLIB$$f51d20a3 类的构造方法
public Bean$$EnhancerByCGLIB$$f51d20a3() {
CGLIB$BIND_CALLBACKS(this);
}
private static final void CGLIB$BIND_CALLBACKS(Object paramObject) {
if(paramObject instanceof Bean$$EnhancerByCGLIB$$f51d20a3) {
Bean$$EnhancerByCGLIB$$f51d20a3 f51d20a3 = (Bean$$EnhancerByCGLIB$$f51d20a3)paramObject;
if(f51d20a3.CGLIB$BOUND) {
return;
}
f51d20a3.CGLIB$BOUND = true;
Object obj = CGLIB$THREAD_CALLBACKS.get();
if(obj != null) {
Callback[] callbacks = (Callback[])obj;
MethodInterceptor interceptor = (MethodInterceptor)callbacks[0];
f51d20a3.CGLIB$CALLBACK_0 = interceptor;
return;
}
if(CGLIB$STATIC_CALLBACKS != null)
f51d20a3.CGLIB$CALLBACK_0 = (MethodInterceptor)CGLIB$STATIC_CALLBACKS[0];
}
}
以上代码主要是为代理类Bean$$EnhancerByCGLIB$$f51d20a3类中的 属性 private MethodInterceptor CGLIB$CALLBACK_0; 进行赋值,也就是 为代理类注册 拦截器(MethodInterceptor )的方法
此时 Bean$$EnhancerByCGLIB$$f51d20a3 实例化完成
再回到例子代码中 bean.setSampleProperty("TEST"); 调用代理类的 setSampleProperty
Bean$$EnhancerByCGLIB$$f51d20a3类的 setSampleProperty方法如下:
public final void setSampleProperty(String paramString) {
MethodInterceptor tmp4_1 = this.CGLIB$CALLBACK_0;
if (tmp4_1 == null) {
CGLIB$BIND_CALLBACKS(this);
}
if (this.CGLIB$CALLBACK_0 != null) {
try {
tmp4_1.intercept(this, CGLIB$setSampleProperty$1$Method, new Object[] {paramString}, CGLIB$setSampleProperty$1$Proxy);
return;
} catch (Throwable e) {
}
}
super.setSampleProperty(paramString);
}
以上代码先 回调 拦截器(MethodInterceptor) intercept 方法, 此时 代码转回 Beans类的 intercept 方法
public Object intercept(Object obj, Method method, Object[] args, MethodProxy proxy) throws Throwable {
Object retValFromSuper = null;
try {
if (!Modifier.isAbstract(method.getModifiers())) {
retValFromSuper = proxy.invokeSuper(obj, args);
}
} finally {
String name = method.getName();
if( name.equals("addPropertyChangeListener")) {
addPropertyChangeListener((PropertyChangeListener)args[0]);
} else if ( name.equals( "removePropertyChangeListener" ) ){
removePropertyChangeListener((PropertyChangeListener)args[0]);
}
if( name.startsWith("set") && args.length == 1 && method.getReturnType() == Void.TYPE ){
char propName[] = name.substring("set".length()).toCharArray();
propName[0] = Character.toLowerCase( propName[0] );
propertySupport.firePropertyChange( new String( propName ) , null , args[0]);
}
}
return retValFromSuper;
}
intercept方法的第4个参数的来源于代理类 Bean$$EnhancerByCGLIB$$f51d20a3 类的初始化静态方法 static {}
CGLIB$getSampleProperty$2$Proxy = MethodProxy.create(localClass2, localClass1, "()Ljava/lang/String;", "getSampleProperty", "CGLIB$getSampleProperty$2");接下来转到 retValFromSuper = proxy.invokeSuper(obj, args); MethodProxy类
public Object invokeSuper(Object obj, Object[] args) throws Throwable {
try {
init();
FastClassInfo fci = fastClassInfo;
return fci.f2.invoke(fci.i2, obj, args);
} catch (InvocationTargetException e) {
throw e.getTargetException();
}
}
再看 init(); 方法
private void init() {
if (fastClassInfo == null) {
synchronized (initLock) {
if (fastClassInfo == null) {
CreateInfo ci = createInfo;
FastClassInfo fci = new FastClassInfo();
fci.f1 = helper(ci, ci.c1);// class net.sf.cglib.samples.Bean
fci.f2 = helper(ci, ci.c2);// class net.sf.cglib.samples.Bean$$EnhancerByCGLIB$$f51d20a3
fci.i1 = fci.f1.getIndex(sig1);// setSampleProperty(Ljava/lang/String;)V class net.sf.cglib.samples.Bean
fci.i2 = fci.f2.getIndex(sig2);// CGLIB$setSampleProperty$1(Ljava/lang/String;)V class net.sf.cglib.samples.Bean$$EnhancerByCGLIB$$f51d20a3
fastClassInfo = fci;
createInfo = null;
}
}
}
}
fci.f1 = helper(ci, ci.c1);// class net.sf.cglib.samples.Bean
private static FastClass helper(CreateInfo ci, Class type) {
FastClass.Generator g = new FastClass.Generator();
g.setType(type);// class net.sf.cglib.samples.Bean class net.sf.cglib.samples.Bean$$EnhancerByCGLIB$$23fe786a
g.setClassLoader(ci.c2.getClassLoader());
g.setNamingPolicy(ci.namingPolicy);
g.setStrategy(ci.strategy);
g.setAttemptLoad(ci.attemptLoad);
return g.create();
}
最终会转到 FastClass类的 generateClass方法
public void generateClass(ClassVisitor v) throws Exception {
new FastClassEmitter(v, getClassName(), type);
}
fci.f2 = helper(ci, ci.c2);// class net.sf.cglib.samples.Bean$$EnhancerByCGLIB$$f51d20a3
以上2行代码 会动态的 创建2个继承 FastClass 的类
一个是 Bean$$FastClassByCGLIB$$f4d01dac 主要是包装 net.sf.cglib.samples.Bean 类
另一个Bean$$EnhancerByCGLIB$$f51d20a3$$FastClassByCGLIB$$e12a516c 主要是包装 net.sf.cglib.samples.Bean$$EnhancerByCGLIB$$f51d20a3(代理类)
具体反编译的代码如下
Bean$$FastClassByCGLIB$$f4d01dac
package net.sf.cglib.samples;
import java.beans.PropertyChangeListener;
import java.lang.reflect.InvocationTargetException;
import net.sf.cglib.core.Signature;
import net.sf.cglib.reflect.FastClass;
public class Bean$$FastClassByCGLIB$$f4d01dac extends FastClass {
public Bean$$FastClassByCGLIB$$f4d01dac(Class paramClass) {
super(paramClass);
}
public int getIndex(Signature paramSignature) {
String tmp4_1 = paramSignature.toString();
switch (tmp4_1.hashCode()) {
case -1725733088:
if (tmp4_1.equals("getClass()Ljava/lang/Class;"))
return 10;
break;
case -1148146316:
if(tmp4_1.equals("addPropertyChangeListener(Ljava/beans/PropertyChangeListener;)V"))
return 3;
case -1026001249:
if(tmp4_1.equals("wait(JI)V"))
return 6;
case -727109664:
if(tmp4_1.equals("getSampleProperty()Ljava/lang/String;"))
return 2;
case -182669826:
case -112787753:
case 243996900:
case 946854621:
case 1116248544:
case 1826985398:
case 1902039948:
case 1913648695:
case 1984935277:
}
return -1;
}
public int getIndex(String paramString, Class[] paramArrayOfClass) {
String tmp3_0 = paramString;
switch (tmp3_0.hashCode()) {
case -2043397483:
if (tmp3_0.equals("getSampleProperty")) {
Class[] tmp112_1 = paramArrayOfClass;
switch (tmp112_1.length) {
case 0:
return 2;
default:
}
}
break;
case -1776922004:
case -1645115555:
case -1295482945:
case -1117363270:
case -1039689911:
case 3641717:
case 147696667:
case 1311416993:
case 1902066072:
case 1950568386:
}
return -1;
}
public int getIndex(Class[] paramArrayOfClass) {
Class[] tmp1_0 = paramArrayOfClass;
switch (tmp1_0.length) {
case 0:
return 0;
default:
}
return -1;
}
public Object invoke(int paramInt, Object paramObject, Object[] paramArrayOfObject) throws InvocationTargetException {
try {
Bean bean = (Bean)paramObject;
switch(paramInt) {
case 0:
return bean.toString();
case 1:
bean.setSampleProperty((String)paramArrayOfObject[0]);
return null;
case 2:
return bean.getSampleProperty();
case 3:
bean.addPropertyChangeListener((PropertyChangeListener)paramArrayOfObject[0]);
return null;
case 4:
bean.removePropertyChangeListener((PropertyChangeListener)paramArrayOfObject[0]);
return null;
case 5:
bean.wait();
return null;
case 6:
bean.wait(((Number)paramArrayOfObject[0]).longValue(), (int)paramArrayOfObject[1]);
return null;
case 7:
bean.wait(((Number)paramArrayOfObject[0]).longValue());
return null;
case 8:
return bean.equals(paramArrayOfObject[0]);
case 9:
return bean.hashCode();
case 10:
return bean.getClass();
case 11:
bean.notify();
return null;
case 12:
bean.notifyAll();
return null;
default:
}
} catch(Throwable ex) {
throw new InvocationTargetException(ex);
}
throw new IllegalArgumentException("Cannot find matching method/constructor");
}
public Object newInstance(int paramInt, Object[] paramArrayOfObject) throws InvocationTargetException {
try {
switch (paramInt) {
case 0:
return new Bean() {
public void removePropertyChangeListener(PropertyChangeListener listener) {
}
public void addPropertyChangeListener(PropertyChangeListener listener) {
}
};
default:
}
} catch (Throwable localThrowable) {
throw new InvocationTargetException(localThrowable);
}
throw new IllegalArgumentException("Cannot find matching method/constructor");
}
public int getMaxIndex() {
return 12;
}
}
Bean$$EnhancerByCGLIB$$f51d20a3$$FastClassByCGLIB$$e12a516c 类
package net.sf.cglib.samples;
import java.lang.reflect.InvocationTargetException;
import net.sf.cglib.core.Signature;
import net.sf.cglib.proxy.Callback;
import net.sf.cglib.reflect.FastClass;
public class Bean$$EnhancerByCGLIB$$f51d20a3$$FastClassByCGLIB$$e12a516c extends FastClass {
public Bean$$EnhancerByCGLIB$$f51d20a3$$FastClassByCGLIB$$e12a516c(Class paramClass) {
super(paramClass);
}
public int getIndex(Signature paramSignature) {
String tmp4_1 = paramSignature.toString();
switch (tmp4_1.hashCode()) {
case -2055565910:
if (tmp4_1.equals("CGLIB$SET_THREAD_CALLBACKS([Lnet/sf/cglib/proxy/Callback;)V"))
return 17;
break;
case -1725733088:
if(tmp4_1.equals("getClass()Ljava/lang/Class;")) {
return 32;
}
break;
case -1682551285:
if(tmp4_1.equals("CGLIB$getSampleProperty$2()Ljava/lang/String;")) {
return 20;
}
break;
case -1649069589:
if(tmp4_1.equals("CGLIB$clone$8()Ljava/lang/Object;")) {
return 26;
}
break;
case -1574182249:
case -1457535688:
case -1411723561:
case -1184739478:
case -1148146316:
case -1026001249:
case -894172689:
case -727109664:
case -623122092:
case -508378822:
case -419626537:
case -182669826:
case -112787753:
case 243996900:
case 246779284:
case 560567118:
case 687209440:
case 811063227:
case 812055105:
case 883767110:
case 946854621:
case 973717575:
case 1116248544:
case 1221173700:
case 1230699260:
case 1365196803:
case 1584330438:
case 1826985398:
case 1902039948:
case 1913648695:
case 1984935277:
}
return 2;
}
public int getIndex(String paramString, Class[] paramArrayOfClass) {
String tmp3_0 = paramString;
switch (tmp3_0.hashCode()) {
case -2083498446:
if (tmp3_0.equals("CGLIB$finalize$5")) {
Class[] tmp272_1 = paramArrayOfClass;
switch (tmp272_1.length) {
case 0:
return 23;
default:
}
}
break;
case -2043397483:
if(tmp3_0.equals("getSampleProperty")) {
Class[] tmp272_1 = paramArrayOfClass;
switch (tmp272_1.length) {
case 0:
return 13;
default:
}
}
case -1776922004:
case -1668635866:
case -1645115555:
case -1295482945:
case -1117363270:
case -1053468136:
case -1039689911:
case -681255906:
case -277508560:
case -124978604:
case -60403779:
case -29025551:
case 3641717:
case 85179481:
case 94756189:
case 147696667:
case 161998109:
case 495524492:
case 539783499:
case 1154623345:
case 1311416993:
case 1543336187:
case 1811874389:
case 1817099975:
case 1902066072:
case 1905679803:
case 1950568386:
case 1951977614:
case 2083511360:
}
return 2;
}
public int getIndex(Class[] paramArrayOfClass) {
Class[] tmp1_0 = paramArrayOfClass;
switch (tmp1_0.length) {
case 0:
return 0;
default:
}
return 2;
}
public Object invoke(int paramInt, Object paramObject, Object[] paramArrayOfObject) throws InvocationTargetException {
try {
if(paramObject instanceof net.sf.cglib.samples.Bean$$EnhancerByCGLIB$$f51d20a3) {
Bean$$EnhancerByCGLIB$$f51d20a3 f51d20a3 = (Bean$$EnhancerByCGLIB$$f51d20a3)paramObject;
switch(paramInt) {
case 0:
f51d20a3.CGLIB$finalize$5();
return null;
case 1:
return f51d20a3.CGLIB$equals$6(paramArrayOfObject[0]);
case 2:
return f51d20a3.CGLIB$toString$0();
case 3:
return f51d20a3.CGLIB$hashCode$7();
case 4:
return f51d20a3.CGLIB$clone$8();
case 5:
return f51d20a3.newInstance((java.lang.Class[])paramArrayOfObject[0], (java.lang.Object[])paramArrayOfObject[1], (net.sf.cglib.proxy.Callback[])paramArrayOfObject[2]);
case 6:
return f51d20a3.newInstance((net.sf.cglib.proxy.Callback)paramArrayOfObject[0]);
case 7:
return f51d20a3.newInstance((net.sf.cglib.proxy.Callback[])paramArrayOfObject[0]);
case 8:
f51d20a3.setCallback(((Number)paramArrayOfObject[0]).intValue(), (Callback)paramArrayOfObject[1]);
return null;
case 9:
return f51d20a3.getCallback(((Number)paramArrayOfObject[0]).intValue());
case 10:
f51d20a3.setCallbacks((Callback[])paramArrayOfObject[0]);
return null;
// 下面省略N个方法
}
}
} catch(Throwable ex) {
throw new InvocationTargetException(ex);
}
throw new IllegalArgumentException("Cannot find matching method/constructor");
}
public Object newInstance(int paramInt, Object[] paramArrayOfObject) throws InvocationTargetException {
try {
switch (paramInt) {
case 0:
return new Bean$$EnhancerByCGLIB$$f51d20a3();
}
} catch (Throwable localThrowable) {
throw new InvocationTargetException(localThrowable);
}
throw new IllegalArgumentException("Cannot find matching method/constructor");
}
public int getMaxIndex() {
return 34;
}
}
之后再转到 MethodProxy类中的 invokeSuper 方法中
public Object invokeSuper(Object obj, Object[] args) throws Throwable {
try {
init();
FastClassInfo fci = fastClassInfo;
return fci.f2.invoke(fci.i2, obj, args);
} catch (InvocationTargetException e) {
throw e.getTargetException();
}
}
return fci.f2.invoke(fci.i2, obj, args);
再看 Bean$$EnhancerByCGLIB$$f51d20a3$$FastClassByCGLIB$$e12a516c 类的invoke方法
public Object invoke(int paramInt, Object paramObject, Object[] paramArrayOfObject) throws InvocationTargetException {
try {
if(paramObject instanceof net.sf.cglib.samples.Bean$$EnhancerByCGLIB$$f51d20a3) {
Bean$$EnhancerByCGLIB$$f51d20a3 f51d20a3 = (Bean$$EnhancerByCGLIB$$f51d20a3)paramObject;
switch(paramInt) {
case 0:
f51d20a3.CGLIB$finalize$5();
return null;
case 1:
return f51d20a3.CGLIB$equals$6(paramArrayOfObject[0]);
case 2:
return f51d20a3.CGLIB$toString$0();
case 3:
return f51d20a3.CGLIB$hashCode$7();
case 4:
return f51d20a3.CGLIB$clone$8();
case 5:
return f51d20a3.newInstance((java.lang.Class[])paramArrayOfObject[0], (java.lang.Object[])paramArrayOfObject[1], (net.sf.cglib.proxy.Callback[])paramArrayOfObject[2]);
case 6:
return f51d20a3.newInstance((net.sf.cglib.proxy.Callback)paramArrayOfObject[0]);
case 7:
return f51d20a3.newInstance((net.sf.cglib.proxy.Callback[])paramArrayOfObject[0]);
case 8:
f51d20a3.setCallback(((Number)paramArrayOfObject[0]).intValue(), (Callback)paramArrayOfObject[1]);
return null;
case 9:
return f51d20a3.getCallback(((Number)paramArrayOfObject[0]).intValue());
case 10:
f51d20a3.setCallbacks((Callback[])paramArrayOfObject[0]);
return null;
// 下面省略N个方法
}
}
} catch(Throwable ex) {
throw new InvocationTargetException(ex);
}
throw new IllegalArgumentException("Cannot find matching method/constructor");
}
在以上的方法中会调到 代理类 Bean$$EnhancerByCGLIB$$f51d20a3 的 CGLIB$setSampleProperty$1 方法
final void CGLIB$setSampleProperty$1(String paramString) {
super.setSampleProperty(paramString);
}
因为 Bean$$EnhancerByCGLIB$$f51d20a3 代理类继承 Bean 类 所以 super.setSampleProperty(paramString); 在调用 Bean 类中的 setSampleProperty方法
到此为止整个代理的过程就结束了.
总结
cglib和JDK 的动态代理区别
cglib 既可以代理类,也可以代理接口, cglib 在代理类时 要继承 目标的类 ,
jdk的动态代理只能代理接口. 只能实现目标的接口
通俗一点说原理吧,
JDK 只能代理接口是因为 它只反射出接口中的所有方法, 然后将所有的方法写到一个新的class文件中,既代理的类,再用native的类的加载器进行加载。
而cglib 代理类, 是反射本类中的所有方法和接口中的所有方法 , 再用类加载加载Class 文件,
cglib 类加载器获取的方式是通过反射
private static Method DEFINE_CLASS; private static final ProtectionDomain PROTECTION_DOMAIN;
static {
PROTECTION_DOMAIN = getProtectionDomain(ReflectUtils.class);
AccessController.doPrivileged(new PrivilegedAction() {
public Object run() {
try {
Class loader = Class.forName("java.lang.ClassLoader"); // JVM crash w/o this
DEFINE_CLASS = loader.getDeclaredMethod(
"defineClass",
new Class[] {
String.class,
byte[].class,
Integer.TYPE,
Integer.TYPE,
ProtectionDomain.class
}
);
DEFINE_CLASS.setAccessible(true);
} catch (ClassNotFoundException e) {
throw new CodeGenerationException(e);
} catch (NoSuchMethodException e) {
throw new CodeGenerationException(e);
}
return null;
}
});
}
public static ProtectionDomain getProtectionDomain(final Class source) {
if(source == null) {
return null;
}
return (ProtectionDomain)AccessController.doPrivileged(new PrivilegedAction() {
public Object run() {
return source.getProtectionDomain();
}
});
}
=======
之前写了一次很详细的过程, 不知怎么回事没保存就闪退了,没保存上, 又写了第二遍, 没有之前的那次写的详细了,/(ㄒoㄒ)/~~.
最后附上完成的工程,有想看的朋友可以下载, 以上有些代码无法反编译,是我自己读asm文件翻转成Java代码的,不一定会100%的准确, 但大致的思路是对的, 如有错误也请大家纠正,谢谢.
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