method interceptor by jdk dynamic proxy

Author: code4craft

src/main/java/us/codecraft/tinyioc/aop/AdvisedSupport.java

@@ -1,7 +1,29 @@
 package us.codecraft.tinyioc.aop;
 
+import org.aopalliance.intercept.MethodInterceptor;
+
 /**
  * @author [email protected]
  */
 public class AdvisedSupport {
+
+	private TargetSource targetSource;
+
+    private MethodInterceptor methodInterceptor;
+
+    public TargetSource getTargetSource() {
+        return targetSource;
+    }
+
+    public void setTargetSource(TargetSource targetSource) {
+        this.targetSource = targetSource;
+    }
+
+    public MethodInterceptor getMethodInterceptor() {
+        return methodInterceptor;
+    }
+
+    public void setMethodInterceptor(MethodInterceptor methodInterceptor) {
+        this.methodInterceptor = methodInterceptor;
+    }
 }

src/main/java/us/codecraft/tinyioc/aop/AopProxyFactory.java

@@ -0,0 +1,32 @@
+package us.codecraft.tinyioc.aop;
+
+import org.aopalliance.intercept.MethodInterceptor;
+
+import java.lang.reflect.InvocationHandler;
+import java.lang.reflect.Method;
+import java.lang.reflect.Proxy;
+
+/**
+ * @author [email protected]
+ */
+public class JdkDynamicAopProxy implements AopProxy, InvocationHandler {
+
+	private AdvisedSupport advised;
+
+    public JdkDynamicAopProxy(AdvisedSupport advised) {
+        this.advised = advised;
+    }
+
+    @Override
+	public Object getProxy() {
+		return Proxy.newProxyInstance(getClass().getClassLoader(), new Class[] { advised.getTargetSource()
+				.getTargetClass() }, this);
+	}
+
+	@Override
+	public Object invoke(final Object proxy, final Method method, final Object[] args) throws Throwable {
+		MethodInterceptor methodInterceptor = advised.getMethodInterceptor();
+		return methodInterceptor.invoke(new ReflectiveMethodInvocation(advised.getTargetSource().getTarget(), method, args));
+	}
+
+}

src/main/java/us/codecraft/tinyioc/aop/JdkDynamicAopProxy.java

@@ -0,0 +1,49 @@
+package us.codecraft.tinyioc.aop;
+
+import org.aopalliance.intercept.MethodInvocation;
+
+import java.lang.reflect.AccessibleObject;
+import java.lang.reflect.Method;
+
+/**
+ * @author [email protected]
+ */
+public class ReflectiveMethodInvocation implements MethodInvocation {
+
+	private Object target;
+
+	private Method method;
+
+	private Object[] args;
+
+	public ReflectiveMethodInvocation(Object target, Method method, Object[] args) {
+		this.target = target;
+		this.method = method;
+		this.args = args;
+	}
+
+	@Override
+	public Method getMethod() {
+		return method;
+	}
+
+	@Override
+	public Object[] getArguments() {
+		return args;
+	}
+
+	@Override
+	public Object proceed() throws Throwable {
+		return method.invoke(target, args);
+	}
+
+	@Override
+	public Object getThis() {
+		return target;
+	}
+
+	@Override
+	public AccessibleObject getStaticPart() {
+		return method;
+	}
+}

src/main/java/us/codecraft/tinyioc/aop/ReflectiveMethodInvocation.java

@@ -0,0 +1,24 @@
+package us.codecraft.tinyioc.aop;
+
+/**
+ * @author [email protected]
+ */
+public class TargetSource {
+
+	private Class targetClass;
+
+	private Object target;
+
+	public TargetSource(Object target, Class<?> targetClass) {
+		this.target = target;
+		this.targetClass = targetClass;
+	}
+
+	public Class getTargetClass() {
+		return targetClass;
+	}
+
+	public Object getTarget() {
+		return target;
+	}
+}

src/main/java/us/codecraft/tinyioc/aop/TargetSource.java

@@ -3,21 +3,7 @@
 /**
  * @author [email protected]
  */
-public class HelloWorldService {
+public interface HelloWorldService {
 
-    private String text;
-
-    private OutputService outputService;
-
-    public void helloWorld(){
-        outputService.output(text);
-    }
-
-    public void setText(String text) {
-        this.text = text;
-    }
-
-    public void setOutputService(OutputService outputService) {
-        this.outputService = outputService;
-    }
+    void helloWorld();
 }

src/test/java/us/codecraft/tinyioc/HelloWorldService.java

@@ -0,0 +1,24 @@
+package us.codecraft.tinyioc;
+
+/**
+ * @author [email protected]
+ */
+public class HelloWorldServiceImpl implements HelloWorldService {
+
+    private String text;
+
+    private OutputService outputService;
+
+    @Override
+    public void helloWorld(){
+        outputService.output(text);
+    }
+
+    public void setText(String text) {
+        this.text = text;
+    }
+
+    public void setOutputService(OutputService outputService) {
+        this.outputService = outputService;
+    }
+}

src/test/java/us/codecraft/tinyioc/HelloWorldServiceImpl.java

@@ -0,0 +1,38 @@
+package us.codecraft.tinyioc.aop;
+
+import org.junit.Test;
+import us.codecraft.tinyioc.HelloWorldService;
+import us.codecraft.tinyioc.context.ApplicationContext;
+import us.codecraft.tinyioc.context.ClassPathXmlApplicationContext;
+
+/**
+ * @author [email protected]
+ */
+public class JdkDynamicAopProxyTest {
+
+	@Test
+	public void testInterceptor() throws Exception {
+		// --------- helloWorldService without AOP
+		ApplicationContext applicationContext = new ClassPathXmlApplicationContext("tinyioc.xml");
+		HelloWorldService helloWorldService = (HelloWorldService) applicationContext.getBean("helloWorldService");
+		helloWorldService.helloWorld();
+
+		// --------- helloWorldService with AOP
+		// 1. 设置被代理对象(Joinpoint)
+		AdvisedSupport advisedSupport = new AdvisedSupport();
+		TargetSource targetSource = new TargetSource(helloWorldService, HelloWorldService.class);
+		advisedSupport.setTargetSource(targetSource);
+
+		// 2. 设置拦截器(Advice)
+		TimerInterceptor timerInterceptor = new TimerInterceptor();
+		advisedSupport.setMethodInterceptor(timerInterceptor);
+
+		// 3. 创建代理(Proxy)
+		JdkDynamicAopProxy jdkDynamicAopProxy = new JdkDynamicAopProxy(advisedSupport);
+		HelloWorldService helloWorldServiceProxy = (HelloWorldService) jdkDynamicAopProxy.getProxy();
+
+        // 4. 基于AOP的调用
+        helloWorldServiceProxy.helloWorld();
+
+	}
+}

src/test/java/us/codecraft/tinyioc/aop/JdkDynamicAopProxyTest.java

@@ -0,0 +1,20 @@
+package us.codecraft.tinyioc.aop;
+
+import org.aopalliance.intercept.MethodInterceptor;
+import org.aopalliance.intercept.MethodInvocation;
+
+/**
+ * @author [email protected]
+ */
+public class TimerInterceptor implements MethodInterceptor {
+
+	@Override
+	public Object invoke(MethodInvocation invocation) throws Throwable {
+		long time = System.nanoTime();
+		System.out.println("Invocation of Method " + invocation.getMethod().getName() + " start!");
+		Object proceed = invocation.proceed();
+		System.out.println("Invocation of Method " + invocation.getMethod().getName() + " end! takes " + (System.nanoTime() - time)
+				+ " nanoseconds.");
+		return proceed;
+	}
+}

src/test/java/us/codecraft/tinyioc/aop/TimerInterceptor.java

@@ -12,7 +12,7 @@
         <property name="helloWorldService" ref="helloWorldService"></property>
     </bean>
 
-    <bean name="helloWorldService" class="us.codecraft.tinyioc.HelloWorldService">
+    <bean name="helloWorldService" class="us.codecraft.tinyioc.HelloWorldServiceImpl">
         <property name="text" value="Hello World!"></property>
         <property name="outputService" ref="outputService"></property>
     </bean>