Spring RESTful服務接收和返回JSON最佳實踐

時間 2019-11-08

標籤 spring restful 服務接收返回 json 最佳實踐欄目 Spring 简体版

原文原文鏈接

我的學習參考所用，勿噴！ html

返回JSON java

1) 用Maven構建web項目： web

構建過程參考limingnihao的blog（寫得至關的詳細！！！）：使用Eclipse構建Maven的SpringMVC項目 ajax

註解@ResponseBody能夠將結果（一個包含字符串和JavaBean的Map），轉換成JSON。因爲Spring是採用對JSON進行了封裝的jackson來生成JSON和返回給客戶端,因此這裏須要添加jackson的相關包。項目的pom.xml配置以下： spring

Xml代碼

<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.watson</groupId>
<artifactId>rest-spring</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>rest-spring Maven Webapp</name>
<url>http://maven.apache.org</url>
<dependencies>
......
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-mapper-asl</artifactId>
<version>1.4.2</version>
</dependency>
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-core-asl</artifactId>
<version>1.4.2</version>
</dependency>
</dependencies>
</project>

2) 在web.xml配置Spring的請求處理的Servlet，具體設置： apache

Xml代碼

<?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" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
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>Spring-Rest</display-name>
<servlet>
<servlet-name>rest</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/rest-servlet.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>rest</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>

3) 在rest-servlet.xml中配置以下： json

Xml代碼

<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>

爲了解決亂碼問題，須要添加以下配置，而且這裏能夠顯示的添加MappingJacksonHttpMessageConverter這個轉換器。瀏覽器

Xml代碼

<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
<property name="messageConverters">
<list>
<bean class="org.springframework.http.converter.StringHttpMessageConverter">
<property name="supportedMediaTypes">
<list>
<value>text/plain;charset=UTF-8</value>
</list>
</property>
</bean>
<bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter" />
</list>
</property>
</bean>

4) 編寫本身的服務組件類，使用MVC的annotation風格，使用 @ResponseBody處理返回值。具體代碼以下： spring-mvc

Java代碼

@RequestMapping("/jsonfeed")
public @ResponseBody Object getJSON(Model model) {
List<TournamentContent> tournamentList = new ArrayList<TournamentContent>();
tournamentList.add(TournamentContent.generateContent("FIFA", new Date(), "World Cup", "www.fifa.com/worldcup/"));
tournamentList.add(TournamentContent.generateContent("FIFA", new Date(), "U-20 World Cup", "www.fifa.com/u20worldcup/"));
tournamentList.add(TournamentContent.generateContent("FIFA", new Date(), "U-17 World Cup", "www.fifa.com/u17worldcup/"));
tournamentList.add(TournamentContent.generateContent("中超", new Date(), "中超", "www.fifa.com/confederationscup/"));
model.addAttribute("items", tournamentList);
model.addAttribute("status", 0);
return model;
}

5)將運行項目，在瀏覽器中輸入http://[host]:[port]/[appname]/jsonfeed.json，例如樓主的實例中輸入以下：http://localhost:7070/rest-spring/jsonfeed/，獲得結果爲： mvc

Json代碼

{"status":0,"items":[{"name":"World Cup","id":8,"link":"www.fifa.com/worldcup/","author":"FIFA","publicationDate":1334559460940},{"name":"U-20 World Cup","id":9,"link":"www.fifa.com/u20worldcup/","author":"FIFA","publicationDate":1334559460940},{"name":"U-17 World Cup","id":10,"link":"www.fifa.com/u17worldcup/","author":"FIFA","publicationDate":1334559460940},{"name":"Confederations Cup","id":11,"link":"www.fifa.com/confederationscup/","author":"FIFA","publicationDate":1334559460940}]}

這裏咱們也能夠利用Spring3MVC中對試圖和內容協商的方法來處理返回JSON的狀況，下面步驟接上面第2步：

3) 在rest-servlet.xml中對相關進行具體的設置：

Xml代碼

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:aop="http://www.springframework.org/schema/aop" xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
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
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.0.xsd">
<context:component-scan base-package="com.watson.rest" />
<bean class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver">
<property name="ignoreAcceptHeader" value="true" />
<property name="defaultContentType" value="text/html" />
<property name="mediaTypes">
<map>
<entry key="html" value="text/html" />
<entry key="pdf" value="application/pdf" />
<entry key="xsl" value="application/vnd.ms-excel" />
<entry key="xml" value="application/xml" />
<entry key="json" value="application/json" />
</map>
</property>
<property name="favorParameter" value="false" />
<property name="viewResolvers">
<list>
<bean class="org.springframework.web.servlet.view.BeanNameViewResolver" />
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.JstlView" />
<property name="prefix" value="/pages" />
<property name="suffix" value=".jsp"></property>
</bean>
</list>
</property>
<property name="defaultViews">
<list>
<bean class="org.springframework.web.servlet.view.json.MappingJacksonJsonView" />
<!--
<bean class="org.springframework.web.servlet.view.xml.MarshallingView">
<property name="marshaller">
<bean class="org.springframework.oxm.xstream.XStreamMarshaller"/>
</property>
</bean>
-->
</list>
</property>
</bean>
</beans>

4)編寫本身的服務組件類，使用MVC的annotation風格，這裏能夠再也不使用@ResponseBody斷言。具體代碼以下：

Java代碼

//FINAL
package com.watson.rest.json;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import com.watson.rest.feeds.TournamentContent;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
@Controller
public class FeedController {
@RequestMapping("/jsonfeed")
public String getJSON(Model model) {
List<TournamentContent> tournamentList = new ArrayList<TournamentContent>();
tournamentList.add(TournamentContent.generateContent("FIFA", new Date(), "World Cup", "www.fifa.com/worldcup/"));
tournamentList.add(TournamentContent.generateContent("FIFA", new Date(), "U-20 World Cup", "www.fifa.com/u20worldcup/"));
tournamentList.add(TournamentContent.generateContent("FIFA", new Date(), "U-17 World Cup", "www.fifa.com/u17worldcup/"));
tournamentList.add(TournamentContent.generateContent("FIFA", new Date(), "Confederations Cup", "www.fifa.com/confederationscup/"));
model.addAttribute("items", tournamentList);
model.addAttribute("status", 0);
return "jsontournamenttemplate";
}
}

這裏的TournamentContent是自定義的POJO類：

Java代碼

public class TournamentContent {
private static int idCounter = 0;
private String author;
private Date publicationDate;
private String name;
private String link;
private int id;
public static TournamentContent generateContent(String author, Date date, String name, String link) {
TournamentContent content = new TournamentContent();
content.author = author;
content.publicationDate = date;
content.name = name;
content.link = link;
content.id = idCounter++;
return content;
}
//省略getter、setter
}

5)將運行項目，在瀏覽器中輸入http://[host]:[port]/[appname]/jsonfeed.json，例如樓主的實例中輸入以下：http://localhost:7070/rest-spring/jsonfeed.json，獲得結果爲：

Json代碼

{"status":0,"items":[{"name":"World Cup","id":8,"link":"www.fifa.com/worldcup/","author":"FIFA","publicationDate":1334559460940},{"name":"U-20 World Cup","id":9,"link":"www.fifa.com/u20worldcup/","author":"FIFA","publicationDate":1334559460940},{"name":"U-17 World Cup","id":10,"link":"www.fifa.com/u17worldcup/","author":"FIFA","publicationDate":1334559460940},{"name":"Confederations Cup","id":11,"link":"www.fifa.com/confederationscup/","author":"FIFA","publicationDate":1334559460940}]}