JdkProxy的进阶知识 - ToB企服应用市场:ToB评测及商务社交产业平台

public interface Fight {
/**
* 射击
*/
void shot();
/**
* 炸弹
*/
void bomb();
}

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public class BeautifulCountryTarget implements Fight {
private static final Logger LOGGER = LoggerFactory.getLogger(BeautifulCountryTarget.class);
/**
* 射击
*/
@Override
public void shot() {
LOGGER.debug("M4 shot ---> big goose!");
}
/**
* 炸弹
*/
@Override
public void bomb() {
LOGGER.debug("HIMARS fire ---> big goose!");
}
}

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public class JdkProxy {
private static final Logger LOGGER = LoggerFactory.getLogger(JdkProxy.class);
/**
* 通过 Proxy.create 生成的对象是代理对象，基于接口的代理对象，那么有以下几点是需要注意
*
* 1：生成的代理对象是实现了目标接口
* 2：生成的代理对象与代理目标是兄弟关系 (都实现了同一个目标接口)
*
*/
public static void main(String[] args) throws InterruptedException {
// jdkProxy
jdkProxyTest();
}
public static void jdkProxyTest() throws InterruptedException {
//类加载器，负责把生成的class($Proxy???)文件加载到JVM
ClassLoader loader = JdkProxy.class.getClassLoader();
//需要代理的目标(对象)
BeautifulCountryTarget target = new BeautifulCountryTarget();
//增强目标方法的处理程序
InvocationHandler handler = (proxy, method, args) -> {
LOGGER.debug("大哥你在旁边看着喝Coffee！，武器开给，我来打！");
//方法调用，（目标对象，参数）
return method.invoke(target, args);
};
//创建代理人
Fight w_k_l_Fight = (Fight)Proxy.newProxyInstance(
loader,
new Class[]{Fight.class},
handler
);
//打印下类路径，方便使用 arthas 进行反张译
LOGGER.debug("proxy<w_k_l_Fight> class {}", w_k_l_Fight.getClass());
//代理人调用方法
w_k_l_Fight.shot();
w_k_l_Fight.bomb();
}
}

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19:22:41.839 [main] DEBUG com.java.coffeetime.aop.JdkProxy -- proxy<w_k_l_Fight> class class jdk.proxy1.$Proxy0
19:22:41.842 [main] DEBUG com.java.coffeetime.aop.JdkProxy -- 大哥你在旁边看着喝Coffee！，武器开给，我来打！
19:22:41.842 [main] DEBUG com.java.coffeetime.aop.BeautifulCountryTarget -- M4 shot ---> big goose!
19:22:41.842 [main] DEBUG com.java.coffeetime.aop.JdkProxy -- 大哥你在旁边看着喝Coffee！，武器开给，我来打！
19:22:41.842 [main] DEBUG com.java.coffeetime.aop.BeautifulCountryTarget -- HIMARS fire ---> big goose!

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/**
* 模拟通过 Proxy.create 出来的 $Proxy?? 类，
*
*/
public class SimulateProxy extends Proxy implements Fight {
protected SimulateProxy(InvocationHandler h) {
super(h);
}
/**
* 射击
*/
@Override
public void shot() {
try {
// 代理的方法
Method pMethod = Fight.class.getMethod("shot");
//调用增强处理器
super.h.invoke(this, pMethod, null);
} catch (Throwable e) {
e.printStackTrace();
}
}
/**
* 炸弹
*/
@Override
public void bomb() {
try {
// 代理的方法
Method pMethod = Fight.class.getMethod("bomb");
//调用增强处理器
super.h.invoke(this, pMethod, null);
} catch (Throwable e) {
e.printStackTrace();
}
}
}

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public class JdkProxy {
private static final Logger LOGGER = LoggerFactory.getLogger(JdkProxy.class);
/**
* 通过 Proxy.create 生成的对象是代理对象，基于接口的代理对象，那么有以下几点是需要注意
*
* 1：生成的代理对象是实现了目标接口
* 2：生成的代理对象与代理目标是兄弟关系 (都实现了同一个目标接口)
*
*/
public static void main(String[] args) throws InterruptedException {
// 模拟代理类
simulateProxyTest();
}
public static void simulateProxyTest() {
//需要代理的目标(对象)
BeautifulCountryTarget target = new BeautifulCountryTarget();
//增强目标方法的函数
InvocationHandler handler = (proxy, method, args) -> {
LOGGER.debug("大哥你在旁边看着喝Coffee！，武器开给，我来打！");
return method.invoke(target, args);
};
//创建代理人这里换成自己手写的
Fight w_k_l_Fight = new SimulateProxy(handler);
//代理人调用方法
w_k_l_Fight.shot();
w_k_l_Fight.bomb();
}
}

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19:38:23.950 [main] DEBUG com.java.coffeetime.aop.JdkProxy -- 大哥你在旁边看着喝Coffee！，武器开给，我来打！
19:38:23.951 [main] DEBUG com.java.coffeetime.aop.BeautifulCountryTarget -- M4 shot ---> big goose!
19:38:23.951 [main] DEBUG com.java.coffeetime.aop.JdkProxy -- 大哥你在旁边看着喝Coffee！，武器开给，我来打！
19:38:23.951 [main] DEBUG com.java.coffeetime.aop.BeautifulCountryTarget -- HIMARS fire ---> big goose!

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public final class $Proxy0 extends Proxy implements Fight {
private static final Method m0;
private static final Method m1;
private static final Method m2;
private static final Method m3;
private static final Method m4;
public $Proxy0(InvocationHandler param1) {
super(var1);
}
public final int hashCode() {
try {
return (Integer)super.h.invoke(this, m0, (Object[])null);
} catch (RuntimeException | Error var2) {
throw var2;
} catch (Throwable var3) {
throw new UndeclaredThrowableException(var3);
}
}
public final boolean equals(Object var1) {
try {
return (Boolean)super.h.invoke(this, m1, new Object[]{var1});
} catch (RuntimeException | Error var2) {
throw var2;
} catch (Throwable var3) {
throw new UndeclaredThrowableException(var3);
}
}
public final String toString() {
try {
return (String)super.h.invoke(this, m2, (Object[])null);
} catch (RuntimeException | Error var2) {
throw var2;
} catch (Throwable var3) {
throw new UndeclaredThrowableException(var3);
}
}
public final void shot() {
try {
super.h.invoke(this, m3, (Object[])null);
} catch (RuntimeException | Error var2) {
throw var2;
} catch (Throwable var3) {
throw new UndeclaredThrowableException(var3);
}
}
public final void bomb() {
try {
super.h.invoke(this, m4, (Object[])null);
} catch (RuntimeException | Error var2) {
throw var2;
} catch (Throwable var3) {
throw new UndeclaredThrowableException(var3);
}
}
static {
try {
m0 = Class.forName("java.lang.Object").getMethod("hashCode");
m1 = Class.forName("java.lang.Object").getMethod("equals", Class.forName("java.lang.Object"));
m2 = Class.forName("java.lang.Object").getMethod("toString");
m3 = Class.forName("com.java.coffeetime.aop.Fight").getMethod("shot");
m4 = Class.forName("com.java.coffeetime.aop.Fight").getMethod("bomb");
} catch (NoSuchMethodException var2) {
throw new NoSuchMethodError(var2.getMessage());
} catch (ClassNotFoundException var3) {
throw new NoClassDefFoundError(var3.getMessage());
}
}
private static Lookup proxyClassLookup(Lookup var0) throws IllegalAccessException {
if (var0.lookupClass() == Proxy.class && var0.hasFullPrivilegeAccess()) {
return MethodHandles.lookup();
} else {
throw new IllegalAccessException(var0.toString());
}
}
}

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