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用Struts2實現在線銀行付款

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posted @ 2009-10-13 18:27 Jxi 閱讀(1201) | 評論 (2) | 編輯 收藏

SSH基礎搭建

 

                           Struts2+Hibernate3.0+Spring的基本搭建(非常基礎的)

具體操作步驟截圖見附件(源代碼不包含lib包):S2SH截圖
除了操作的配置代碼:
WEB-INF下的web.xml的配置:

applicationContext.xml:

struts.xml:
hibernate.cfg.xml:什么都做，全交給Spring管理
WEB-INF下的數據庫配置文件 jdbc.properties

posted @ 2009-09-30 15:29 Jxi 閱讀(144) | 評論 (0) | 編輯 收藏

Spring @AspectJ

準備工作:需要  spring/lib/asm 下的3個包:asm.jar  asm-commons.jar asm-util.jar
spring/lib/aspectj  下的2個包 aspectjrt.jar  和aspectjweaver.jar
使用@AspectJ的小例子:

posted @ 2009-09-14 20:01 Jxi 閱讀(157) | 評論 (0) | 編輯 收藏

Spring AOP 學習筆記

AOP  Aspect Oriented Programing  面向方面編程
AOP 術語
連接點:(Joinpoint)    程序執行的特定位置(類開始初始化前、類初始化后、調用前后、異常拋出后)
切點:   (PointCut)     程序類中客觀存在的事物（類中的方法）
增強 :  (Advice)        置入到目標類Joinpint的一段代碼
目標對象:(Target)   引介(Introduction)  織入(Weaving)  代理(Proxy) 切面(Aspect):切點和增強的組成 
 
基礎知識: Spring Aop :使用動態代理技術在運行期間織入增強代碼
ProxyFactory 代理工廠采用JDK代理或CGLib代理技術
JDK 動態代理:
1.定義UserService接口函數:

public interface UserService {
public void addUser(int id);
 }

2.UserServiceImpl

public class UserServiceImpl implements UserService{
 public void addUser(int id){
     System.out.println("添加一個用戶中 ："+id);
 }
}

3.ProxyHandler

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;


public class ProxyHandler implements InvocationHandler{
   private Object target;
   public  ProxyHandler(Object target){
       this.target=target;
   }
   
public Object invoke(Object proxy, Method method, Object[] args)
        throws Throwable {
       System.out.println("添加用戶前");
       Object obj=method.invoke(target,args);
       System.out.println("添加用戶后");
       return obj;
}
}

TestProxyHandler

import java.lang.reflect.Proxy;

public class ProxyHandlerTest {
  public static void main(String args[]){
      UserService target=new UserServiceImpl();
      ProxyHandler handler=new ProxyHandler(target);
      UserService proxy=(UserService)Proxy.newProxyInstance(
        target.getClass().getClassLoader(),
        target.getClass().getInterfaces(),
        handler);
      proxy.addUser(100);
  }
}

CGLib 代理:
AddUserService接口:

package CGlib.Text.Service;

public interface AddUserService {
 public void addUser(int id);
}

AddUserServiceImpl 實現類:

package CGlib.Text.Service;

public class AddUserServiceImpl implements AddUserService {

    public void addUser(int id) {
        System.out.println("添加用戶ID中:"+id);
    }
}

CglibProxy 代理類:

package CGlib.Text.Service;



import java.lang.reflect.Method;

import net.sf.cglib.proxy.Enhancer;
import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;

public class CglibProxy implements MethodInterceptor{
    private Enhancer enhancer=new Enhancer();
    @SuppressWarnings("unchecked")
    public Object getProxy(Class clazz){
        enhancer.setSuperclass(clazz);
        enhancer.setCallback(this);
        return enhancer.create();        
    }

    public Object intercept(Object obj, Method method, Object[] args,
            MethodProxy proxy) throws Throwable {
        System.out.println("添加用戶之前");
        System.out.print(method.getName());
        System.out.print(obj.getClass().getName()+"外加");
        System.out.print(args.getClass().getName());
        Object result=proxy.invokeSuper(obj, args);
        System.out.println("外加的參數"+args.toString());
        System.out.println("添加用戶之后");
        // TODO Auto-generated method stub
        return result;
    }
    

}

CglibProxyTest:測試類

package CGlib.Text.Service;

public class CglibProxyTest {
    public static void main(String[] args){
        CglibProxy proxy=new CglibProxy();
        AddUserServiceImpl userService=
            (AddUserServiceImpl)proxy.getProxy(AddUserServiceImpl.class);
      userService.addUser(100);        
    }

}

對JDK動態代理和Cglib動態代理的理解：
JDK   代理時性能高，但生成代理對象時運行性能較低
Cglib 代理時性能低，但生成代理對象時運行性能較高
所以：單例Singleton 時采用CGLib代理。

posted @ 2009-08-23 22:52 Jxi 閱讀(137) | 評論 (0) | 編輯 收藏

Spring

 

Spring

Important

Spring is an application framework. Unlike single-tier frameworks such as Struts or Hibernate, Spring aims to help structure whole applications in a consistent, productive manner, pulling together best-of-breed single-tier frameworks to create a coherent architecture.

Problems with the Traditional Approach to J2EE

傳統J2EE方法存在的問題

• J2EE applications tend to contain excessive amounts of "plumbing" code.多
• Many J2EE applications use a distributed object model where this is inappropriate.雜
• The EJB component model is unduly complex.不當
• EJB is overused.過度使用
• Many "J2EE design patterns" are not, in fact, design patterns, but workarounds for technology limitations.技術跟不上
• J2EE applications are hard to unit test.測試難
• Certain J2EE technologies have simply failed.

Enter Spring

接觸Spring

• Inversion of Control container:倒置控制
• Aspect-Oriented Programming (AOP) framework:
• Data access abstraction:
• JDBC simplification:
• Transaction management:
• MVC web framework:
• Simplification for working with JNDI, JTA, and other J2EE APIs:
• Lightweight remoting:
• JMS support:
• JMX support:
• Support for a comprehensive testing strategy for application developers:

The key Spring values can be summarized as follows:

·         Spring is a non-invasive framework.非侵入

·         Spring provides a consistent programming model, usable in any environment.

·         Spring aims to promote code reuse.復用

·         Spring aims to facilitate Object Oriented design in J2EE applications.

·         Spring aims to facilitate good programming practice, such as programming to interfaces, rather than classes.面向接口

·         Spring promotes pluggability.性能

·         Spring facilitates the extraction of configuration values from Java code into XML or properties files.

·         Spring is designed so that applications using it are as easy as possible to test.

·         Spring is consistent.

·         Spring promotes architectural choice.

·         Spring does not reinvent the wheel.

posted @ 2009-07-25 14:57 Jxi 閱讀(152) | 評論 (0) | 編輯 收藏