The AspectJ of spring implements AOP

First, the annotation-based ASPECTJ

1. To use ASPECTJ annotations in spring applications, you must include the AspectJ class library under Classpath:

Com.springsource.org.aopalliance.jar and Com.springsource.org.aspectj.weaver.jar; Adding an AOP schema to the <beans> root element ; Enable ASPECTJ direct support in the spring IOC container, as long as an empty XML element is defined in the Bean configuration file <aop:aspectj-autoproxy>; When the spring IOC container detects the bean The <aop:aspectj-autoproxy> element in the configuration file automatically creates a proxy for the bean that matches the aspectj slice.

2. Notification is a simple Java method labeled with some annotations, and ASPECTJ supports 5 types of notification annotations:

1) @Before: Pre-notification, execution before method execution

2) @After: Ultimate Enhancement

3) @AfterReturning: Post notification, execute after method returns result

4) @AfterThrowing: Exception notification, executed after the method throws an exception

5) @Around: Surround notification, around the execution of the method

3. A typical pointcut expression is to match various methods according to the signature of the method:

-execution (* * * * (.. ): The first * represents the matching of any modifier and return value, the second * represents an object of any class, and the third * represents any method in the argument list: Match any number of parameters.

-Execution (* com.bupt.springtest.aop.arithmeticcalculator.* (..)) : Matches all methods declared in Arithmeticcalculator, the first * represents any modifier and any return value; the second * represents either method; Match any number of parameters. If the target class or interface is in the same package as the slice, the package name can be omitted.

-Execution (Public * arithmeticcalculator.* (..))       : Matches all public methods in the Arithmeticcalculator class. -Execution (public double arithmeticcalculator.* (..)) : A method that matches the value returned in a double type in arithmeticcalculator

-Execution (public double arithmeticcalculator.* (double,..)) : match the first parameter to a method of type double. Match any number of arguments of any type

-Execution (public double arithmeticcalculator.* (double, Double)): A method that matches the parameter type double, double type

4. Case

1. Create an interface

Package Cn.happy.service;public interface Isomeservice {public    void Dosome ();    Public String Add ();    public void Insert ();    public void Update ();    public void Delete ();    public void Select ();

2. Implement the Interface class

Package Cn.happy.service;public class Someservice implements Isomeservice {public    void Dosome () {        System.out.println ("Code  OK");    }    Public String Add () {        System.out.println ("=========log log ===============");        int i = 5/0;        return "Add";    }    public void Insert () {        System.out.println ("Insert");    }    public void Update () {        System.out.println ("Update");    }    public void Delete () {        System.out.println ("delete");    }    public void Select () {        int i = 5/0;        System.out.println ("select");}    }

3. Writing Enhanced Classes

Package Cn.happy.service;import Org.aspectj.lang.proceedingjoinpoint;import org.aspectj.lang.annotation.*;@ Aspectpublic class Myaspect {@Before (value= "Execution (* *).    Service.*.* (..)) ")    public void Myaspectj () {System.out.println ("---I am the predecessor Enhancement---"); } @AfterReturning (value= "Execution (* *).    Service.*.* (..)) ")    public void Myaspectjafter () {System.out.println ("---I am post enhancement---"); } @Around (value= "Execution (* *).    Service.*.* (..)) ") Public Object Myaspectjaround (Proceedingjoinpoint proceedingjoinpoint) throws Throwable {System.out.println ("---i am        Enhanced---") around the front;        Object result = Proceedingjoinpoint.proceed ();        SYSTEM.OUT.PRINTLN ("---I was surrounded by enhanced---");  if (result!= null) {string str = (string) result;        The return value can be changed to str.touppercase ();        } else {return null; }} Exception Enhancement @Pointcut ("Execution (* *).  Service.*.* (..)) ") expression annotation public void Mypoincut () {} @AfterThrowing ("Mypoincut ()") publicvoid throwing () {SYSTEM.OUT.PRINTLN ("---error---"); }//Tangent expression @Pointcut ("Execution (* *).    Service.*.insert (..)) ") public void Insert () {} @Pointcut ("Execution (* *):    Service.*.update (..)) ") public void Update () {} @Pointcut (Execution (* *).    Service.*.delete (..)) ") public void Delete () {} @Before ("Insert () | | | Update () | |    Delete () ") public void Myaspectj () {System.out.println ("---I am the predecessor enhancement Opens the thing---"); }//Final enhancement @After ("Execution (* *).    Service.*.* (..)) ")    public void After () {System.out.println ("I am the final enhancement"); }}

　　

4. Writing an XML configuration file

<?xml version= "1.0" encoding= "UTF-8"? ><beans xmlns= "Http://www.springframework.org/schema/beans"       xmlns:aop= "HTTP://WWW.SPRINGFRAMEWORK.ORG/SCHEMA/AOP"       xmlns:p= "http://www.springframework.org/schema/p"       xmlns:xsi= "http://www.w3.org/2001/XMLSchema-instance"       xsi:schemalocation= "        http// Www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd/         http WWW.SPRINGFRAMEWORK.ORG/SCHEMA/AOP http://www.springframework.org/schema/aop/spring-aop.xsd ">    <!-- Annotation implementation-    <!--target Object--    <bean id= "Someservice" class= "Cn.happy.serviceXML.SomeService" ></ Bean>      <!--enhancement  notification –&gt   -    <bean id= "Beforeadvice" class= " Cn.happy.service.MyAspect "></bean>    <aop:aspectj-autoproxy></aop:aspectj-autoproxy>        </beans>

5. Write Test class

Package Cn.happy;import Cn.happy.service.isomeservice;import Org.junit.test;import Org.springframework.context.applicationcontext;import Org.springframework.context.support.classpathxmlapplicationcontext;public class Test {    @Test public  void  Testaspect () {        ApplicationContext context = new Classpathxmlapplicationcontext ("Applicationcontext.xml ");        Isomeservice Someservice = (isomeservice) context.getbean ("Someservice");        Someservice.insert ();        Someservice.update ();        Someservice.delete ();        Someservice.select ();    }}

　　

Second, XML-based ASPECTJ implementation

1. XML-based implementations need to include the <aop> node in the XML configuration file.

2. Case

1) Create an interface class

Package Cn.happy.servicexml;public interface Isomeservice {public    void Dosome ();    Public String Add ();}

2) Implement the interface class

Package Cn.happy.servicexml;public class Someservice implements Isomeservice {public    void Dosome () {        System.out.println ("Code  OK");    }    Public String Add () {        System.out.println ("log------");        int i = 5/0;        return "Add";}    }

3) Writing Enhanced classes

Package Cn.happy.servicexml;import Org.aspectj.lang.proceedingjoinpoint;public class Myaspect {public    void Mybefore () {        System.out.println ("=========before============");    }    public void After () {        System.out.println ("============after===============");    }    Public Object Myarround (Proceedingjoinpoint proceedingjoinpoint) throws Throwable {        System.out.println ("I am enhanced before wrapping" );        Object result = Proceedingjoinpoint.proceed ();        System.out.println ("I was enhanced after surround");        if (result!= null) {            string str = (string) result;  The return value can be changed  str.touppercase ();        } else {            return null;        }    
}

4). Writing an XML configuration file

<?xml version= "1.0" encoding= "UTF-8"? ><beans xmlns= "Http://www.springframework.org/schema/beans" xmlns: aop= "HTTP://WWW.SPRINGFRAMEWORK.ORG/SCHEMA/AOP" xmlns:p= "http://www.springframework.org/schema/p" xmlns:xsi= "H Ttp://www.w3.org/2001/xmlschema-instance "xsi:schemalocation=" Http://www.springframework.org/schema/beans HT Tp://www.springframework.org/schema/beans/spring-beans.xsd HTTP://WWW.SPRINGFRAMEWORK.ORG/SCHEMA/AOP/HTTP Www.springframework.org/schema/aop/spring-aop.xsd > <!--target objects--<bean id= "Someservice" class= "Cn.happy . Servicexml.someservice "></bean> <!--Enhanced Class--<bean id=" aspect "class=" Cn.happy.serviceXML.MyAspe CT ></bean> <!--aop--> <aop:config> <!--set a pointcut--<aop:pointcut id= "Mycu T "expression=" Execution (* *). Servicexml.*.* (..)) " ></aop:pointcut> <aop:aspect ref= "aspect" > <aop:before method= "Mybefore" pointcut-ref= "Mycut" ></aop:before> <!--<aop:after-returning method= "after" pointcut-ref= "Mycut" ;</aop:after-returning>--> <!--<aop:around method= "Myarround" pointcut-ref= "Mycut" ></aop:ar Ound>--> </aop:aspect> </aop:config></beans>

5) Writing test classes

Package Cn.happy;import Cn.happy.servicexml.isomeservice;import Org.junit.test;import Org.springframework.context.applicationcontext;import Org.springframework.context.support.classpathxmlapplicationcontext;public class Test01 {    //AspectJ XML    @ Test public    void Testaspectxml () {        ApplicationContext context = new Classpathxmlapplicationcontext (" Applicationcontext.xml ");        Isomeservice someservice= (Isomeservice) Context.getbean ("Someservice");        Someservice.add ();        Someservice.dosome ();    }}

　　

　　

　　

　　

　　

The AspectJ of spring implements AOP