一、Spring与Servlet的整合

1.1：

　　　　加入Spring的jar包。（要加web.jar包）

1.2：
- 　　java工程中获取Spring的上下文对象。

ApplicationContext context = new ClassPathXmlApplicationContext("spring.xml")来初始化Spring的上下文环境。

- 　　WEB工程中初始化Spring的上下文环境。

在web.xml中添加监听器（ContextLoaderListener继承ContextLoader类，ContextLoader的静态常量CONFIG_LOCATION_PARAM = "contextConfigLocation"
ContextLoaderListener读取Spring默认文件的位置就是"contextConfigLocation"的值，而这个值可以在web.xml <context-param>标签里设置contextConfigLocation）：　　　　如下：

  <listener>

        <listener-class>

            org.springframework.web.context.ContextLoaderListener

        </listener-class>

    </listener>

ContextLoaderListener读取Spring默认文件的位置：/WEB-INF/applicationContext.xml
可以改变读取的位置。配置context-param参数。

  <context-param>

        <param-name>contextConfigLocation</param-name>

        <param-value>classpath:spring.xml</param-value>

    </context-param>

如上配置，ContextLoaderListener类负责初始化spring的上下文环境，其路径为spring.xml。

　　1.3　　spring与servlet 的整合

sping有三大特性： IOC(控制反转)/DI(依赖注入)/AOP(面向切面编程、代理模式),而servlet是单例模式只实例一次，一般我们使用servlet的时候并不定义成员属性，因为成员属性会被所有用户所共用，而DI是通过属性注入的方式这样就会冲突，所以servlet+spring只能使用spring中的IOC和AOP两种特性进行编程。

　　1.4　　案例

index.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"

    pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<% String path=request.getContextPath(); %>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<title>Insert title here</title>

</head>

<body>

    <a href="<%=path%>/servlet/exam"> spring和servlet整合</a>

</body>

</html>

web.xml

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">

  <display-name>spring_servlet</display-name>

  <welcome-file-list>

    <welcome-file>index.html</welcome-file>

    <welcome-file>index.htm</welcome-file>

    <welcome-file>index.jsp</welcome-file>

    <welcome-file>default.html</welcome-file>

    <welcome-file>default.htm</welcome-file>

    <welcome-file>default.jsp</welcome-file>

  </welcome-file-list>

  <context-param>

      <param-name>contextConfigLocation</param-name>

      <param-value>classpath:spring.xml</param-value>

  </context-param>

  <listener>

      <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>

  </listener>

  
 <!-- 这个servlet只用于创建ApplicationContext对象，并不被人访问所以无须配置servlet-mapping -->
  <servlet>
      <servlet-name>loderServlet</servlet-name>
      <servlet-class>servlet.LoderServlet</servlet-class>
      <load-on-startup>1</load-on-startup>
  </servlet>
 <!-- end -->

  <servlet>

      <servlet-name>exam</servlet-name>

      <servlet-class>servlet.Example</servlet-class>

  </servlet>

  <servlet-mapping>

      <servlet-name>exam</servlet-name>

      <url-pattern>/servlet/exam</url-pattern>

  </servlet-mapping>

</web-app>

spring.xml

<?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:context="http://www.springframework.org/schema/context"

    xmlns:aop="http://www.springframework.org/schema/aop"

    xmlns:tx="http://www.springframework.org/schema/tx"

    xsi:schemaLocation="http://www.springframework.org/schema/beans

    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd

    http://www.springframework.org/schema/context

        http://www.springframework.org/schema/context/spring-context-3.0.xsd

    http://www.springframework.org/schema/tx

    http://www.springframework.org/schema/tx/spring-tx-3.0.xsd

    http://www.springframework.org/schema/aop

    http://www.springframework.org/schema/aop/spring-aop-3.0.xsd">

    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">

        <constructor-arg index="0"  name="driverClassName" value="com.mysql.jdbc.Driver" ></constructor-arg>

        <constructor-arg index="1" name="url"  value="jdbc:mysql://127.0.0.1:3306/user?useUnicode=true&amp;characterEncoding=UTF-8" ></constructor-arg>

        <constructor-arg index="2" name="username" value="root"></constructor-arg>

        <constructor-arg index="3" name="password" value=""></constructor-arg>

    </bean>

    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">

        <property name="dataSource" ref="dataSource"></property>

    </bean>

    <tx:advice id="advice_1" transaction-manager="transactionManager">

        <tx:attributes>

            <tx:method name="update*" propagation="REQUIRED"/>

        </tx:attributes>

    </tx:advice>

    <aop:config proxy-target-class="true">

        <aop:pointcut expression="execution(* service..*.*(..))" id="poin_1"/>

        <aop:advisor advice-ref="advice_1" pointcut-ref="poin_1"/>

    </aop:config>

    <bean id="testService" class="service.TestService">

        <property name="roledao">

            <bean class="dao.RoleDao">

                <property name="dataSource" ref="dataSource"></property>

            </bean>

        </property>

        <property name="userdao">

            <bean class="dao.UserDao">

                <property name="dataSource" ref="dataSource"></property>

            </bean>

        </property>

    </bean>

    </beans>

Example.java

package servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.springframework.context.ApplicationContext;

import org.springframework.web.context.support.WebApplicationContextUtils;

import service.TestService;

public class Example extends HttpServlet{

    @Override

    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        this.doPost(req, resp);

    }

    @Override

    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        TestService testService=(TestService)LoderServlet.getBean("testService");
        
        testService.update();

    }

}

LoderServlet.java

package servlet;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import org.springframework.context.ApplicationContext;

import org.springframework.web.context.support.WebApplicationContextUtils;

import org.springframework.web.jsf.el.WebApplicationContextFacesELResolver;

public class LoderServlet extends HttpServlet {

    private static ApplicationContext context=null;

    @Override

    public void init() throws ServletException {

        System.out.println("初始化servlet");

        if(context==null){

            context=WebApplicationContextUtils.getWebApplicationContext(this.getServletContext());

        }

    }

    public static Object getBean(String beanName){

        Object bean=null;

        bean=context.getBean(beanName);

        return bean;

    }

    @Override

    public void destroy() {

        // TODO Auto-generated method stub

        super.destroy();

    }

}

TestService.java

package service;

import dao.RoleDao;

import dao.UserDao;

public class TestService {

    private UserDao userdao;

    private RoleDao roledao;

    public void setUserdao(UserDao userdao) {

        this.userdao = userdao;

    }

    public void setRoledao(RoleDao roledao) {

        this.roledao = roledao;

    }

    public boolean update(){

        boolean flag=false;

        try {

            this.userdao.update_1();

            this.roledao.update_2();

            flag=true;

        } catch (Exception e) {

            e.printStackTrace();

            flag=false;

            throw new RuntimeException(e);

        }

        return flag;

    }

}

RoleDao.java

package dao;

import org.springframework.jdbc.core.support.JdbcDaoSupport;

public class RoleDao extends JdbcDaoSupport {

    public void update_2(){

        this.getJdbcTemplate().update("update role set role_name='aa' where role_id=1 ");

        this.getJdbcTemplate().update("update role set role_name='bb' where role_id=2 ");

}

}

UserDao.java

package dao;

import org.springframework.jdbc.core.support.JdbcDaoSupport;

public class UserDao extends JdbcDaoSupport{

    public void update_1(){

        this.getJdbcTemplate().update("update user set age=111 where userName='张三'");

        this.getJdbcTemplate().update("update user set age=111 where userName='李四'");

}

}

结果：

在Example类中调用TestService的update方法，这个方法又调用了UserDao的update_1方法和RoleDao的update_2方法，如果update_2方法出现异常，则update_1和update_2方法

同时回滚。本例实现了servlet+spring的事务管理。

本题代码在：链接

巴特西

（四）spring+servlet 整合

一、Spring与Servlet的整合

1.1：

1.2：

1.3　　spring与servlet 的整合

1.4　　案例

最新文章

热门文章

巴特西

（四）spring+servlet 整合

一、Spring与Servlet的整合

1.1：

1.2：

1.3 spring与servlet 的整合

1.4 案例

最新文章

热门文章

　　1.3　　spring与servlet 的整合

　　1.4　　案例