spring mvc实现Restful返回json格式数据

在本示例中，我们将向您展示如何将对象转换成json格式并通过spring mvc框架返回给用户。

使用技术及环境：

Spring 3.2.2.RELEASE
Jackson 1.9.10
JDK 1.6
Eclipse 3.6
Maven 3

PS：在spring 3 中，要输出json数据，只需要添加Jackson 库到你的classpath。

1、项目依赖

spring和jackson的依赖：

<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/maven-v4_0_0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<groupId>com.mkyong.common</groupId>
	<artifactId>SpringMVC</artifactId>
	<packaging>war</packaging>
	<version>1.0-SNAPSHOT</version>
	<name>SpringMVC Json Webapp</name>
	<url>http://maven.apache.org</url>
	<properties>
		<spring.version>3.2.2.RELEASE</spring.version>
		<jackson.version>1.9.10</jackson.version>
		<jdk.version>1.6</jdk.version>
	</properties>
	<dependencies>
		<!-- Spring 3 dependencies -->
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-core</artifactId>
			<version>${spring.version}</version>
		</dependency>
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-web</artifactId>
			<version>${spring.version}</version>
		</dependency>
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-webmvc</artifactId>
			<version>${spring.version}</version>
		</dependency>
		<!-- Jackson JSON Mapper -->
		<dependency>
			<groupId>org.codehaus.jackson</groupId>
			<artifactId>jackson-mapper-asl</artifactId>
			<version>${jackson.version}</version>
		</dependency>
	</dependencies>
	<build>
		<finalName>SpringMVC</finalName>
		<plugins>
		  <plugin>
			<groupId>org.apache.maven.plugins</groupId>
			<artifactId>maven-eclipse-plugin</artifactId>
			<version>2.9</version>
			<configuration>
				<downloadSources>true</downloadSources>
				<downloadJavadocs>false</downloadJavadocs>
				<wtpversion>2.0</wtpversion>
			</configuration>
		  </plugin>
		  <plugin>
			<groupId>org.apache.maven.plugins</groupId>
			<artifactId>maven-compiler-plugin</artifactId>
			<version>2.3.2</version>
			<configuration>
				<source>${jdk.version}</source>
				<target>${jdk.version}</target>
			</configuration>
		  </plugin>
		</plugins>
	</build>
</project>

2、Model

一个简单的JavaBean，稍后将被转换成json格式输出。

public class Shop {
	String name;
	String staffName[];
	//getter and setter methods
}

3、Controller

添加@ResponseBody到返回值，我们看到：

Jackson 包已经在项目的 classpath
mvc:annotation-driven注解已经启用
返回方法已经添加了@ResponseBody

spring会自动处理json的转换。

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;
import org.springframework.web.bind.annotation.ResponseBody;
import com.mkyong.common.model.Shop;
@Controller
@RequestMapping("/kfc/brands")
public class JSONController {
	@RequestMapping(value="{name}", method = RequestMethod.GET)
	public @ResponseBody Shop getShopInJSON(@PathVariable String name) {
		Shop shop = new Shop();
		shop.setName(name);
		shop.setStaffName(new String[]{"mkyong1", "mkyong2"});
		return shop;
	}
}

4、mvc:annotation-driven

在你的spring配置文件中启用mvc:annotation-driven注解。

<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:mvc="http://www.springframework.org/schema/mvc" 
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	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/mvc
        http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">
	<context:component-scan base-package="com.mkyong.common.controller" />
	<mvc:annotation-driven />
</beans>

5、示例结果

访问URL：http://localhost:8080/SpringMVC/rest/kfc/brands/kfc-kampar

原文链接：http://www.mkyong.com/spring-mvc/spring-3-mvc-and-json-example/