Spring3.0兑现REST实例

Spring3.0实现REST实例Spring从3.0开始将全面支持rest。不得不感叹Spring的强大。项目结构:第一步:配置web.x

Spring3.0实现REST实例

Spring从3.0开始将全面支持rest。不得不感叹Spring的强大。

项目结构:


第一步:配置web.xml文件

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

<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee"

    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 

    http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">

    <display-name></display-name>

    <context-param>

        <!--rest配置文件的路径,貌似不配置也是加载这个地址,这个地方有点疑问,大家指点指点 -->

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

        <param-value>/WEB-INF/rest-servlet.xml</param-value>

    </context-param>

    <listener>

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

    </listener>

    <servlet>

        <!-- 配置一个Servlet,有这个Servlet统一调度页面的请求 -->

        <servlet-name>rest</servlet-name>

        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

        <load-on-startup>2</load-on-startup>

    </servlet>

    <servlet-mapping>



        <servlet-name>rest</servlet-name>

        <url-pattern>/</url-pattern>

    </servlet-mapping>

    <welcome-file-list>

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

    </welcome-file-list>

</web-app>

   第二步:配置rest-servlet.xml这个文件

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

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

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

    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-2.5.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd"

    default-lazy-init="true">



    <description>Spring公共配置</description>



    <!--检测注解 -->

    <context:component-scan base-package="com.bijian" />

    <bean

        />

    <bean

        />

    <!-- 注册视图解析器,说白了就是根据返回值指定到某个页面 -->

    <bean id="viewResolver"

        />

        <property name="prefix" value="/"></property> <!--页面文件的路径,在根目录下 -->

    </bean>

</beans>



第三步:具体实现类

package com.bijian.controller;



import java.io.IOException;



import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;



import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.PathVariable;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;



@Controller

@RequestMapping("/simple")

public class SimpleController {

    //映射路径/simple/index当访问这个路径时,执行这个方法

    @RequestMapping("/index")

    public String index(HttpServletRequest request ,HttpServletResponse response){

               //response,request会自动传进来

        request.setAttribute("message", "Hello,这是一个Spring3 REST的实例!");

        return "index.jsp";

    }

  

    //根据ID获取不同的内容,通过@PathVariable 获得属性

    @RequestMapping(value="/{id}",method=RequestMethod.GET)

    public String get(@PathVariable String id,HttpServletRequest request ,HttpServletResponse response) throws IOException{

        request.setAttribute("message", "Hello,这是一个Spring3 REST的实例!<br/>ID:"+id+"");

       //response.getWriter().write("You put id is : "+id);

        return "index.jsp";

        //return null;

    }

}



第四步:index.jsp页面

<%@ page language="java" pageEncoding="UTF-8"%>

<html>

  <head>

    <title>Spring3 RESTful</title>

   </head>

  

  <body>

    ${message}

   </body>

</html>

在浏览器中输入:http://localhost:8080/SpringREST2/simple/index,就可以看到效果。


  也可以在页面输入不同的参数,获得不同的内容,输入地址:http://localhost:8080/SpringREST2/simple/abc,这次执行的就是get方法,通过注解获取ID值,效果:



关于Spring rest 对于Ajax的支持,其实响应Ajax就是通过response返回一个字符串到页面,既然能获得response对象,那问题就迎刃而解了,我们改造下get方法:

//根据ID获取不同的内容,通过@PathVariable 获得属性

    @RequestMapping(value="/{id}",method=RequestMethod.GET)

    publicString get(@PathVariableString id,HttpServletRequest request ,HttpServletResponse response) throws IOException{

        //request.setAttribute("message", "Hello,这是一个Spring3 REST的实例!<br/>ID:"+id+"");

    response.getWriter().write("You put id is : "+id);

        //return "index.jsp";

        return null;

    }

改造index.jsp页面:

<%@ page language="java" pageEncoding="UTF-8"%>

<html>

  <head>

    <title>Spring3 RESTful</title>

    <SCRIPT TYPE="text/javascript">

            function go(value){

                var url = "/SpringREST2/simple/"+value+"/";

                var request =  newXMLHttpRequest();

                request.open("GET", url, true);

                request.setRequestHeader("Content-Type","application/x-javascript;");

                request.onreadystatechange = function() {

                    if (request.readyState == 4) {

                        if (request.status == 200){

                            if (request.responseText) { 

                                document.getElementByIdx_x_x_x_x("text").innerHTML = request.responseText;

                            }

                        }

                    }

                };

                request.send(null);

            }

        </SCRIPT>

  </head>

  

  <body>

    ${message}

    <br>

    请输入您将访问的Id标识:<input id="id" type="text" size="7"><input type="button" value="Go" onclick="go(document.getElementByIdx_x_x_x_x('id').value)">

    <div id="text"></div>

  </body>

</html>

  访问http://localhost:8080/SpringREST2/simple/index,在页面里的输入框中输入值,可以看到返回的数据: