springboot返回json數據
創建項目前準備
待STS完全展開後，點擊導航欄的 Window -> Prefences 5. 彈出Prefences窗口，在左側導航欄選擇Server -> Runtime Environment ；
如果已經存在Tomcat環境，就跳過。否則點擊右側的Add按鈕，選擇Apache Tomcat 8.5，Next。然後選擇 Tomcat的安裝目錄，Finish。
新建springboot項目--Spring Starter Project
1.選擇依賴
2.配置pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<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>com.example</groupId>
<artifactId>springboot-mybatis-demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>spring-boot</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.10.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.1</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.6</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<!-- mybatis generator 自動生成代碼插件 -->
<plugin>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-maven-plugin</artifactId>
<version>1.3.1</version>
<configuration>
<configurationFile>${basedir}/src/main/resources/generator/generatorConfig.xml</configurationFile>
<overwrite>true</overwrite>
<verbose>true</verbose>
</configuration>
</plugin>
</plugins>
</build>
</project>
3.啓動類App代碼：
package com.example;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class ApplicationTest {
public static void main(String[] args) {
SpringApplication.run(ApplicationTest.class, args);
}
}
4.application.yml (最好手敲。。。容易出錯)
server:
context-path: /demo
spring:
datasource:
url: jdbc:mysql://localhost:3306/springboot?useSSL=false&characterEncoding=utf-8
username: root
password: root
driver-class-name: com.mysql.jdbc.Driver
jpa:
database: MYSQL
show-sql: true
hibernate:
ddl-auto: update
naming:
strategy: org.hibernate.cfg.ImprovedNamingStrategy
properties:
hibernate:
dialect: org.hibernate.dialect.MySQL5Dialect
thymeleaf:
cache: false
實體類代碼：
package com.example.entity;
import java.math.BigDecimal;
public class User {
private BigDecimal id;
private String username;
private String sex;
public BigDecimal getId() {
return id;
}
public void setId(BigDecimal id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
}
第一種方式@RestController：
package com.example.Controller;
import java.math.BigDecimal;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import com.example.entity.User;
@RestController
public class TestController {
@RequestMapping("/")
public User test(){
User user = new User();
user.setId(new BigDecimal(12));
user.setSex("12");
user.setUsername("phpfzh");
return user;
}
}
運行項目：
右擊項目 點擊 run As ==> Maven clear ====> maven install
右擊項目 點擊 run As ===> java application ===》 在瀏覽器輸入：localhost：8080/
輸出：
{"id":12,"username":"phpfzh","sex":"12"}
第二種方式@ResponseBody：
package com.example.Controller;
import java.math.BigDecimal;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import com.phpfzh.mode.User;
@Controller
public class TestController2 {
@ResponseBody
@RequestMapping("/test2")
public User test2(){
User user = new User();
user.setId(new BigDecimal(12));
user.setSex("12");
user.setUsername("phpfzh-test2");
return user;
}
}
運行項目：
右擊項目 點擊 run As ==> Maven clear ====> maven install
右擊項目 點擊 run As ===> java application ===》 在瀏覽器輸入：localhost：8080/test2
瀏覽器輸出：
{"id":12,"username":"phpfzh-test2","sex":"12"}
第三種方式response：
在pom.xml 添加 阿里巴巴json jar包：
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.20</version>
</dependency>
Controller代碼：
package com.example.Controller;
import java.io.PrintWriter;
import java.math.BigDecimal;
import javax.servlet.http.HttpServletResponse;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import com.alibaba.fastjson.JSON;
import com.example.entity.User;
@Controller
public class TestController3 {
@RequestMapping("/test3")
public String test(HttpServletResponse response){
User user = new User();
user.setId(new BigDecimal(12));
user.setSex("12");
user.setUsername("phpfzh-test3");
String date = JSON.toJSONString(user);
try {
sendJsonData(response, date);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
protected void sendJsonData(HttpServletResponse response, String data) throws Exception { response.setContentType("text/html;charset=UTF-8"); PrintWriter out = response.getWriter(); out.println(data); out.flush(); out.close(); } }