01 json环境搭建

1 导包

　　

 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <groupId>cn.xiangxu.note</groupId>
   <artifactId>testNote</artifactId>
   <version>0.0.1-SNAPSHOT</version>
   <packaging>war</packaging>
   <dependencies>
       <dependency>
           <groupId>org.springframework</groupId>
           <artifactId>spring-webmvc</artifactId>
           <version>3.2.8.RELEASE</version>
       </dependency>
       <dependency>
           <groupId>com.fasterxml.jackson.core</groupId>
           <artifactId>jackson-annotations</artifactId>
           <version>2.2.3</version>
       </dependency>
       <dependency>
           <groupId>com.fasterxml.jackson.core</groupId>
           <artifactId>jackson-core</artifactId>
           <version>2.2.3</version>
       </dependency>
       <dependency>
           <groupId>com.fasterxml.jackson.core</groupId>
           <artifactId>jackson-databind</artifactId>
           <version>2.2.3</version>
       </dependency>
   </dependencies>
 </project>

jar包的pom.xml

2 配置实体类

　　> 有包

　　> 实现序列化接口【要添加序列版本号】

　　> 有无参构造器

　　> 生成set/get方法 【serialVersionUID不用实现】

　　> 生成toString方法

　　> 有id属性的实体类需要重写equals/hashcode方法 【只选id就行啦】

 package cn.xiangxu.testNote.entity;

 import java.io.Serializable;

 public class User implements Serializable {

     private static final long serialVersionUID = 8786891263198147115L;

     private Integer id;
     private String name;
     private String address;

     public User(Integer id, String name, String address) {
         super();
         this.id = id;
         this.name = name;
         this.address = address;
     }
     public User() {
         super();
         // TODO Auto-generated constructor stub
     }
     public Integer getId() {
         return id;
     }
     public void setId(Integer id) {
         this.id = id;
     }
     public String getName() {
         return name;
     }
     public void setName(String name) {
         this.name = name;
     }
     public String getAddress() {
         return address;
     }
     public void setAddress(String address) {
         this.address = address;
     }
     @Override
     public String toString() {
         return "User [id=" + id + ", name=" + name + ", address=" + address + "]";
     }
     @Override
     public int hashCode() {
         final int prime = 31;
         int result = 1;
         result = prime * result + ((id == null) ? 0 : id.hashCode());
         return result;
     }
     @Override
     public boolean equals(Object obj) {
         if (this == obj)
             return true;
         if (obj == null)
             return false;
         if (getClass() != obj.getClass())
             return false;
         User other = (User) obj;
         if (id == null) {
             if (other.id != null)
                 return false;
         } else if (!id.equals(other.id))
             return false;
         return true;
     }

 }
 package cn.xiangxu.testNote.entity;

 import java.io.Serializable;

 public class User implements Serializable {

     private static final long serialVersionUID = 8786891263198147115L;

     private Integer id;
     private String name;
     private String address;

     public User(Integer id, String name, String address) {
         super();
         this.id = id;
         this.name = name;
         this.address = address;
     }
     public User() {
         super();
         // TODO Auto-generated constructor stub
     }
     public Integer getId() {
         return id;
     }
     public void setId(Integer id) {
         this.id = id;
     }
     public String getName() {
         return name;
     }
     public void setName(String name) {
         this.name = name;
     }
     public String getAddress() {
         return address;
     }
     public void setAddress(String address) {
         this.address = address;
     }
     @Override
     public String toString() {
         return "User [id=" + id + ", name=" + name + ", address=" + address + "]";
     }
     @Override
     public int hashCode() {
         final int prime = 31;
         int result = 1;
         result = prime * result + ((id == null) ? 0 : id.hashCode());
         return result;
     }
     @Override
     public boolean equals(Object obj) {
         if (this == obj)
             return true;
         if (obj == null)
             return false;
         if (getClass() != obj.getClass())
             return false;
         User other = (User) obj;
         if (id == null) {
             if (other.id != null)
                 return false;
         } else if (!id.equals(other.id))
             return false;
         return true;
     }

 }

实体类

3 在web.xml配置文件中配置前端控制器、spring容器

　　

 <?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" version="2.5">
   <display-name>testNote</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>

   <!-- 配置前端控制器 -->
   <servlet>
       <servlet-name>mvc</servlet-name>
       <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
       <init-param> <!-- 通过参数注入的方式配置spring容器 -->
           <param-name>contextConfigLocation</param-name>
           <param-value>classpath:conf/spring_*.xml</param-value>
       </init-param>
   </servlet>
   <servlet-mapping>
       <servlet-name>mvc</servlet-name>
       <url-pattern>*.do</url-pattern>
   </servlet-mapping>

 </web-app>

web.xml

4 在spring.xml文件中配置组件扫描和mvc注解扫描

　　

 <?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:context="http://www.springframework.org/schema/context"
     xmlns:jdbc="http://www.springframework.org/schema/jdbc"
     xmlns:jee="http://www.springframework.org/schema/jee"
     xmlns:tx="http://www.springframework.org/schema/tx"
     xmlns:aop="http://www.springframework.org/schema/aop"
     xmlns:mvc="http://www.springframework.org/schema/mvc"
     xmlns:util="http://www.springframework.org/schema/util"
     xmlns:jpa="http://www.springframework.org/schema/data/jpa"
     xsi:schemaLocation="
         http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
         http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd
         http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.2.xsd
         http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.2.xsd
         http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
         http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsd
         http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
         http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd
         http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.2.xsd">

     <!-- 启用mvc注解驱动 -->
     <mvc:annotation-driven></mvc:annotation-driven>

     <!-- 组件扫描
         注意：可以同时配置多个包，包之间用逗号隔开;可以不用写到具体哪个包 -->
     <context:component-scan base-package="cn.xiangxu.testNote,com.xiangxu"></context:component-scan>

 </beans>

spring_mvc.xml

5 编写请求分发代码

　　

 package cn.xiangxu.testNote.web;

 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.ResponseBody;

 import cn.xiangxu.testNote.entity.User;

 @Controller
 public class TestController {

     @RequestMapping("/json.do")
     @ResponseBody
     public User json() {
         User user = new User(333, "warrior", "重庆/虎门");
         return user;
     }
 }

请求分发代码

6 启动Tomcat进行测试

　　

7 项目结构【eclipse中的maven工程】