Java動態代理(JDK 和CGLIB、Javassist、ASM之間的差別)
阿新 • • 發佈:2018-12-13
- import com.foo.proxy.Rechargable;
- import com.foo.proxy.Vehicle;
- import java.lang.reflect.InvocationHandler;
- import java.lang.reflect.Method;
- import java.lang.reflect.Proxy;
- import java.lang.reflect.UndeclaredThrowableException;
- /**
- 生成的動態代理類的組織模式是繼承Proxy類,然後實現需要實現代理的類上的所有介面,而在實現的過程中,則是通過將所有的方法都交給了InvocationHandler來處理
- */
- public final class ElectricCarProxy extends Proxy
- implements Rechargable, Vehicle
- {
- private static Method m1;
- private static Method m3;
- private static Method m4;
- private static Method m0;
- private static Method m2;
- public ElectricCarProxy(InvocationHandler paramInvocationHandler)
- throws
- {
- super(paramInvocationHandler);
- }
- public final boolean equals(Object paramObject)
- throws
- {
- try
- { // 方法功能實現交給InvocationHandler處理
- return ((Boolean)this.h.invoke(this, m1, new Object[] { paramObject })).booleanValue();
- }
- catch (Error|RuntimeException localError)
- {
- throw localError;
- }
- catch (Throwable localThrowable)
- {
- throw new UndeclaredThrowableException(localThrowable);
- }
- }
- public final void recharge()
- throws
- {
- try
- {
- // 方法功能實現交給InvocationHandler處理
- this.h.invoke(this, m3, null);
- return;
- }
- catch (Error|RuntimeException localError)
- {
- throw localError;
- }
- catch (Throwable localThrowable)
- {
- throw new UndeclaredThrowableException(localThrowable);
- }
- }
- public final void drive()
- throws
- {
- try
- {
- // 方法功能實現交給InvocationHandler處理
- this.h.invoke(this, m4, null);
- return;
- }
- catch (Error|RuntimeException localError)
- {
- throw localError;
- }
- catch (Throwable localThrowable)
- {
- throw new UndeclaredThrowableException(localThrowable);
- }
- }
- public final int hashCode()
- throws
- {
- try
- {
- // 方法功能實現交給InvocationHandler處理
- return ((Integer)this.h.invoke(this, m0, null)).intValue();
- }
- catch (Error|RuntimeException localError)
- {
- throw localError;
- }
- catch (Throwable localThrowable)
- {
- throw new UndeclaredThrowableException(localThrowable);
- }
- }
- public final String toString()
- throws
- {
- try
- {
- // 方法功能實現交給InvocationHandler處理
- return (String)this.h.invoke(this, m2, null);
- }
- catch (Error|RuntimeException localError)
- {
- throw localError;
- }
- catch (Throwable localThrowable)
- {
- throw new UndeclaredThrowableException(localThrowable);
- }
- }
- static
- {
- try
- { //為每一個需要方法物件,當呼叫相應的方法時,分別將方法物件作為引數傳遞給InvocationHandler處理
- m1 = Class.forName("java.lang.Object").getMethod("equals", new Class[] { Class.forName("java.lang.Object") });
- m3 = Class.forName("com.foo.proxy.Rechargable").getMethod("recharge", new Class[0]);
- m4 = Class.forName("com.foo.proxy.Vehicle").getMethod("drive", new Class[0]);
- m0 = Class.forName("java.lang.Object").getMethod("hashCode", new Class[0]);
- m2 = Class.forName("java.lang.Object").getMethod("toString", new Class[0]);
- return;
- }
- catch (NoSuchMethodException localNoSuchMethodException)
- {
- throw new NoSuchMethodError(localNoSuchMethodException.getMessage());
- }
- catch (ClassNotFoundException localClassNotFoundException)
- {
- throw new NoClassDefFoundError(localClassNotFoundException.getMessage());
- }
- }
- }