Spring Learning-Manual implementation of AOP programming

AOP-oriented tangent programming

AOP allows for complete separation of "business code" and "Focus Code"

  @Override public    list<message> findallmessage () {        session session = NULL;  Attention Point Code        Transaction tx = null;        try{            session = Hibernateutils.getsession ();            tx = Session.begintransaction ();  Attention Point code            Query q = Session.createquery ("From Message Order by write_time Desc"); Business code            return Q.list ();  Business code        }catch (Exception e) {            throw new RuntimeException (e);  Attention Point Code        }finally {            tx.commit ();            Session.close ();  Attention Point code        }    }

　　

Analysis:

The focus code refers to the code that executes repeatedly.

Business code and attention Point code separation, benefits?

--Focus code write once.

-developers need to focus on their core business

--During operation, the dynamic implantation of the focus code when executing the business code; (Proxy implementation)

How to Detach

Cross-Program/object/proxy mode separation

To implement an AOP programming example manually:

Package Aop;import org.springframework.stereotype.component;/** * Created is cxspace on 16-8-10.    */@Component//Join IOC container public class Aop {//execute code public void begin () {System.out.println ("Start transaction");    } public void Commite () {System.out.println ("Commit Transaction"); }}package aop;/** * Created by Cxspace on 16-8-10. */public interface Iuserdao {public void Save ();} Package Aop;import org.springframework.stereotype.component;import javax.annotation.resource;/** * Created by Cxspace On 16-8-10.    */@Componentpublic class Userdao implements iuserdao{@Resource private AOP AOP;        @Override public void Save () {Aop.begin (); SYSTEM.OUT.PRINTLN ("Save data!        ");    Aop.commite (); }}<?xml version= "1.0" encoding= "UTF-8"? ><beans xmlns= "Http://www.springframework.org/schema/beans" xmlns: Xsi= "Http://www.w3.org/2001/XMLSchema-instance" xmlns:p= "http://www.springframework.org/schema/p" Xmlns:contex T= "Http://www.springframework.org/schema/context "xsi:schemalocation=" Http://www.springframework.org/schema/beans http://www.springframework. Org/schema/beans/spring-beans.xsd Http://www.springframework.org/schema/context HTTP://WWW.SPRINGFRAMEWORK.O Rg/schema/context/spring-context.xsd > <!--open annotation Scan-<context:component-scan base-package= "AOP" > </context:component-scan></beans>package Aop;import Org.junit.test;import Org.springframework.context.applicationcontext;import org.springframework.context.support.classpathxmlapplicationcontext;/** * Created by Cxspace on 16-8-10.    */public class App {applicationcontext AC = new Classpathxmlapplicationcontext ("Aop/bean.xml");        @Test public void Test () {Iuserdao Userdao = (Iuserdao) ac.getbean ("Userdao");    Userdao.save (); }}

Package aopproxy;/** * Created by Cxspace on 16-8-10. */public interface Iuserdao {public void Save ();} Package Aopproxy;import org.springframework.stereotype.component;/** * Created is cxspace on 16-8-10. */@Componentpublic class Userdao implements Iuserdao {@Override public void Save () {System.out.println ("Save number According to    "); }}package aopproxy;import org.springframework.stereotype.component;/** * Created by Cxspace on 16-8-10.    */@Component//Join IOC container public class Aop {//execute code public void begin () {System.out.println ("Start transaction");    } public void Commite () {System.out.println ("Commit Transaction"); }}package Aopproxy;import Java.lang.reflect.invocationhandler;import Java.lang.reflect.method;import java.lang.reflect.proxy;/** * Created by Cxspace on 16-8-10.    */public class Proxyfactory {//target object private static object target;    private static AOP AOP;       Generate proxy object method public static object Getproxyinstance (Object Target_,aop aop_) {target = target_; AOP = Aop_; Return Proxy.newproxyinstance (Target.getclass (). getClassLoader (), Target.getclass (). Getinte Rfaces (), new Invocationhandler () {@Override public Object invoke (Ob                        Ject Proxy, method method, object[] args) throws Throwable {Aop.begin ();                        Object returnvalue = Method.invoke (Target,args);                        Aop.commite ();                    Return returnvalue;    }                }        ); }}<?xml version= "1.0" encoding= "UTF-8"? ><beans xmlns= "Http://www.springframework.org/schema/beans" xmlns: Xsi= "Http://www.w3.org/2001/XMLSchema-instance" xmlns:p= "http://www.springframework.org/schema/p" Xmlns:contex t= "Http://www.springframework.org/schema/context" xsi:schemalocation= "http://www.springframework.org/schema/ Beans Http://www.springframework.org/schema/beans/spring-beans.xSD Http://www.springframework.org/schema/context Http://www.springframework.org/schema/context/spring-contex T.xsd > <!--open annotation Scan-<context:component-scan base-package= "Aopproxy" ></context:component-scan&    Gt <!--call the factory method, return the object after the Userdao agent--<bean id= "Userdao_proxy" class= "Aopproxy.proxyfactory" factory-method= " Getproxyinstance "> <constructor-arg index=" 0 "ref=" Userdao "></constructor-arg> <constructo R-arg index= "1" ref= "AOP" ></constructor-arg> </bean></beans>package aopproxy;import Org.junit.test;import Org.springframework.context.applicationcontext;import org.springframework.context.support.classpathxmlapplicationcontext;/** * Created by Cxspace on 16-8-10.    */public class App {applicationcontext AC = new Classpathxmlapplicationcontext ("Aopproxy/bean.xml");        @Test public void Test () {Iuserdao Userdao = (Iuserdao) ac.getbean ("Userdao_proxy"); SYSTEM.OUT.PRINTLN (USerdao.getclass ());    Userdao.save (); }}

　　

Spring Learning-Manual implementation of AOP programming