aop几个常用的切入点指示符匹配规则

秒速五厘米 2022-06-12 03:56 112阅读 0赞

**1.execution：用于匹配方法执行的连接点**

execution(modifiers-pattern? ret-type-pattern declaring-type-pattern?name-pattern(param-pattern) throws-pattern?)
    其中各项的语义如下
    modifiers-pattern：方法的可见性，如public，protected；
    ret-type-pattern：方法的返回值类型，如int，void等；
    declaring-type-pattern：方法所在类的全路径名，如com.spring.Aspect；
    name-pattern：方法名类型，如buisinessService()；
    param-pattern：方法的参数类型，如java.lang.String；throws-pattern：
    方法抛出的异常类型，如java.lang.Exception；
    example:execution(public * com.spring.service.BusinessObject.businessService(java.lang.String,..))

package com.htt.app.loan.service.aop;
    
    import com.htt.app.loan.api.annotation.CheckAop;
    import org.aspectj.lang.annotation.*;
    
    /**
     * Created by sunnyLu on 2017/6/13.
     */
    @Aspect
    public class AopCache {
    
    //  @Pointcut("execution (* com.htt.app.loan.service.impl.*.*(..))")
        @Pointcut("execution (* com.htt.app.loan.service.impl.LoanServiceImpl.getLoan(long,String)) && args(p1,p2)")
        public void pointcut(long p1,String p2){}
    
        @Before(value = "pointcut(p1,p2)")
        public void validate(long p1,String p2) throws Throwable {
            System.out.println("进入前置通知");
            System.out.println("参数："+p1+";"+p2);
        }
    
    }

**匹配LoanService的getLoan(long arg,String arg)方法，且可以得到传入参数**

**2.within****：any join point (method execution only in Spring AOP) within the service package or a sub-package**

package com.htt.app.loan.service.aop;
    
    import com.htt.app.loan.api.annotation.CheckAop;
    import org.aspectj.lang.annotation.*;
    
    /**
     * Created by sunnyLu on 2017/6/13.
     */
    @Aspect
    public class AopCache {
    
        @Pointcut(value = "within(com.htt.app.loan.service.impl..*)")
        public void pointcut(){}
    
        @Before(value = "pointcut()")
        public void validateAnnotation(JoinPoint joinPoint) throws Throwable {
            System.out.println(joinPoint.getArgs());
        }
    
    }

**匹配包及其子包下所有的方法,其最小粒度为类**

**3.this：****any join point (method execution only in Spring AOP) where the proxy implements the `LoanService` interface**

**匹配目标对象的代理对象类型是指定类型（jkd动态代理基于接口，其代理对象继承了proxy，实现了目标接口；cglib动态代理基于类，其代理对象是目标对象的子类，这里须要注意。）请与target区分，后者是匹配目标对象。**

package com.htt.app.loan.service.aop;
    
    import com.htt.app.loan.api.annotation.CheckAop;
    import org.aspectj.lang.annotation.*;
    
    /**
     * Created by sunnyLu on 2017/6/13.
     */
    @Aspect
    public class AopCache {
    
        @Pointcut(value = "this(com.htt.app.loan.api.service.LoanService) && args(p1,p2)")
        public void pointcut(long p1,String p2){}
    
        @Before(value = "pointcut(p1,p2)")
        public void validateAnnotation(long p1,String p2) throws Throwable {
            System.out.println("进入前置通知");
            System.out.println("参数："+p1+";"+p2);
        }
    
    }

**匹配所有LoanService的接口且为以上两个参数的**

**4.@annotation****：用于匹配当前执行方法持有指定注解的方法**

**自定义的注解**

package com.htt.app.loan.api.annotation;
    
    import java.lang.annotation.ElementType;
    import java.lang.annotation.Retention;
    import java.lang.annotation.RetentionPolicy;
    import java.lang.annotation.Target;
    
    /**
     * Created by sunnyLu on 2017/7/14.
     */
    @Retention(RetentionPolicy.RUNTIME)
    @Target(ElementType.METHOD)
    public @interface CheckAop {
        String value() default "no description";
    }

**在接口上使用该注解**

@Service("LoanServiceImpl")
    public class LoanServiceImpl extends ServiceBase implements LoanService {
    
        @Override
        @CheckAop
        public BigDecimal testAop(TestParam testParam) {
            return null;
        }
    
    }

**切入点配置**

package com.htt.app.loan.service.aop;
    
    import com.htt.app.loan.api.annotation.CheckAop;
    import org.aspectj.lang.annotation.*;
    
    /**
     * Created by sunnyLu on 2017/6/13.
     */
    @Aspect
    public class AopCache {
    
        @Pointcut(value="@annotation(ano)",argNames = "ano")
        public void pointcut(CheckAop ano){}
    
        @Before(value = "pointcut(ano)")
        public void validateAnnotation(CheckAop ano) throws Throwable {
            System.out.println("注解式通知"+ano.value());
        }
    
    }

**5.@within：****any join point (method execution only in Spring AOP) where the declared type of the target object has an `@Transactional` annotation**

**自定义的类级别注解**

package com.htt.app.loan.api.annotation;
    
    import java.lang.annotation.ElementType;
    import java.lang.annotation.Retention;
    import java.lang.annotation.RetentionPolicy;
    import java.lang.annotation.Target;
    
    /**
     * Created by sunnyLu on 2017/7/14.
     */
    @Retention(RetentionPolicy.RUNTIME)
    @Target(ElementType.TYPE)
    public @interface CheckWithin {
        String value() default "no description";
    }

**在类上加注解**

@CheckWithin
    @Service("LoanServiceImpl")
    public class LoanServiceImpl extends ServiceBase implements LoanService {
    
        @Override
        @CheckAop
        public BigDecimal testAop(TestParam testParam) {
            return null;
        }
    
    }

切入点配置

package com.htt.app.loan.service.aop;
    
    import org.aspectj.lang.annotation.*;
    
    /**
     * Created by sunnyLu on 2017/6/13.
     */
    @Aspect
    public class AopCache {
    
        @Pointcut(value="@within(com.htt.app.loan.api.annotation.CheckWithin)")
        public void pointcut(){}
    
        @Before(value = "pointcut()")
        public void validateAnnotation() throws Throwable {
            System.out.println("注解式通知");
        }
    
    }

匹配注解修饰的类的所有接口（这个类须要有public方法，否则不会被aop代理）