使用Spring方法拦截器MethodInterceptor

目录

• Spring方法拦截器MethodInterceptor
  • 前言
• Spring拦截器实现+后台原理(MethodInterceptor)
  • MethodInterceptor
    • MethodInterceptor接口
    • AspectJ的注解
    • 简单介绍下关键词
    • 切面设置
    • execution表达式
    • 下面分析下Spring @Aspect

public class TestMethodInterceptor  {
    public static void main(String[] args) {
        ProxyFactory proxyFactory=new ProxyFactory();
        proxyFactory.setTarget(new TestMethodInterceptor());
        proxyFactory.addAdvice(new adviseMethodInterceptor());
        Object proxy = proxyFactory.getProxy();
        TestMethodInterceptor methodInterceptor = (TestMethodInterceptor) proxy;
        methodInterceptor.doSomeThing("通过代理工厂设置代理对象，拦截代理方法");
    }
    public static class adviseMethodInterceptor implements MethodInterceptor{
        @Override
        public Object invoke(MethodInvocation methodInvocation) throws Throwable {
            Object result=null;
            try{
                System.out.println("方法执行之前："+methodInvocation.getMethod().toString());
                result= methodInvocation.proceed();
                System.out.println("方法执行之后："+methodInvocation.getMethod().toString());
                System.out.println("方法正常运行结果："+result);
                return result;
            }catch (Exception e){
                System.out.println("方法出现异常:"+e.toString());
                System.out.println("方法运行Exception结果："+result);
                return result;
            }
        }
    }
    public String doSomeThing(String someThing){
        //int i=5/0;
        return "执行被拦截的方法："+someThing;
    }
}

import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
public class MethodInvokeInterceptor implements MethodInterceptor {
    @Override
    public Object invoke(MethodInvocation methodInvocation) throws Throwable {
        System.out.println("before method invoke....");
        Object object = methodInvocation.proceed();
        System.out.println("after method invoke.....");
        return object;
    }
}

<!-- 拦截器 demo -->
    <bean id="methodInvokeInterceptor" class="com.paic.phssp.springtest.interceptor.method.MethodInvokeInterceptor"/>
    <aop:config>
        <!--切入点,controlller -->
        <aop:pointcut id="pointcut_test"   expression="execution(* com.paic.phssp.springtest.controller..*.*(..))" />
        <!--在该切入点使用自定义拦截器 ,按照先后顺序执行 -->
        <aop:advisor pointcut-ref="pointcut_test" advice-ref="methodInvokeInterceptor" />
    </aop:config>
    <!-- 自动扫描使用了aspectj注解的类 -->
    <aop:aspectj-autoproxy/>

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;
@Aspect
@Component
public class AutoAspectJInterceptor {
    @Around("execution (* com.paic.phssp.springtest.controller..*.*(..))")
    public Object around(ProceedingJoinPoint point) throws Throwable{
        System.out.println("AutoAspectJInterceptor begin around......");
        Object object = point.proceed();
        System.out.println("AutoAspectJInterceptor end around......");
        return object;
    }
}

"execution(public * com.xhx.springboot.controller.*.*(..))"

within(com.xhx.springboot..*)

"@within(org.springframework.stereotype.Component)"

"@annotation(IDataSource)"

import java.lang.annotation.*;
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD})
public @interface IDataSource {
    String value() default "dataSource";
}

@Nullable
    public BeanDefinition parse(Element element, ParserContext parserContext) {
        AopNamespaceUtils.registerAspectJAnnotationAutoProxyCreatorIfNecessary(parserContext, element);
        this.extendBeanDefinition(element, parserContext);
        return null;
    }

public static void registerAspectJAnnotationAutoProxyCreatorIfNecessary(ParserContext parserContext, Element sourceElement) {
        BeanDefinition beanDefinition = AopConfigUtils.registerAspectJAnnotationAutoProxyCreatorIfNecessary(parserContext.getRegistry(), parserContext.extractSource(sourceElement));
        useClassProxyingIfNecessary(parserContext.getRegistry(), sourceElement);
        registerComponentIfNecessary(beanDefinition, parserContext);
    }

@Nullable
    public static BeanDefinition registerAspectJAnnotationAutoProxyCreatorIfNecessary(BeanDefinitionRegistry registry, @Nullable Object source) {
        return registerOrEscalateApcAsRequired(AnnotationAwareAspectJAutoProxyCreator.class, registry, source);
    }

public AopProxy createAopProxy(AdvisedSupport config) throws AopConfigException {
        if (!config.isOptimize() && !config.isProxyTargetClass() && !this.hasNoUserSuppliedProxyInterfaces(config)) {
            return new JdkDynamicAopProxy(config);
        } else {
            Class<?> targetClass = config.getTargetClass();
            if (targetClass == null) {
                throw new AopConfigException("TargetSource cannot determine target class: Either an interface or a target is required for proxy creation.");
            } else {
                return (AopProxy)(!targetClass.isInterface() && !Proxy.isProxyClass(targetClass) ? new ObjenesisCglibAopProxy(config) : new JdkDynamicAopProxy(config));
            }
        }
    }