项目结构图如下：
下面分步骤一一讲解：
第一步，在pom.xml中添加相应依赖：
<pre>
<?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>spring-boot-sample-helloworld</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>spring-boot-sample-helloworld</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.3.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-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.0.0</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
</pre>
第二步，新建application.properties
<pre>
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/jeesite
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.max-idle=10
spring.datasource.max-wait=10000
spring.datasource.min-idle=5
spring.datasource.initial-size=5
server.port=8080
server.session.timeout=10
server.tomcat.uri-encoding=UTF-8
mybatis-config路径
mybatis.config=classpath:mybatis-config.xml
mapper文件路径
mybatis.mapperLocations=classpath:mappers/*.xml
domain object's package
mybatis.typeAliasesPackage=com.example.springbootsamplehelloworld.bean
</pre>
<pre>
package com.example.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
</pre>
第三步，创建bean,mapper,service,controller
<pre>
package com.example.springbootsamplehelloworld.bean;
import java.util.Date;
public class AppMessage {
private String id;
private String message;
private Date senddate;
public AppMessage(){
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id == null ? null : id.trim();
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message == null ? null : message.trim();
}
public Date getSenddate() {
return senddate;
}
public void setSenddate(Date senddate) {
this.senddate = senddate;
}
}
</pre>
<pre>
package com.example.springbootsamplehelloworld.mapper;
import java.util.List;
import com.example.springbootsamplehelloworld.bean.AppMessage;
public interface AppMessageMapper {
int deleteByPrimaryKey(String id);
int insert(AppMessage record);
int insertSelective(AppMessage record);
AppMessage selectByPrimaryKey(String id);
int updateByPrimaryKeySelective(AppMessage record);
int updateByPrimaryKey(AppMessage record);
List<AppMessage> selectAll();
List<AppMessage> getMessById(String id);
public void init();
}
</pre>
<pre>
package com.example.springbootsamplehelloworld.service;
import java.util.ArrayList;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.example.springbootsamplehelloworld.bean.AppMessage;
import com.example.springbootsamplehelloworld.mapper.AppMessageMapper;
@Service
public class AppMessageService {
@Autowired
private AppMessageMapper mapper;
public List<AppMessage> getMessage(){
List<AppMessage> list = new ArrayList<AppMessage>();
list.add(mapper.selectByPrimaryKey("1"));
//list = mapper.selectAll();
return list;
}
public List<AppMessage> getAllMessage(){
List<AppMessage> list = new ArrayList<AppMessage>();
list = mapper.selectAll();
return list;
}
public int addMessage(AppMessage appMessage) {
return mapper.insert(appMessage);
}
public List<AppMessage> getMessageById(String id) {
return mapper.getMessById(id);
}
public int delMessage(String id) {
return mapper.deleteByPrimaryKey(id);
}
}
<pre>
<pre>
package com.example.springbootsamplehelloworld.controller;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import com.example.springbootsamplehelloworld.bean.AppMessage;
import com.example.springbootsamplehelloworld.service.AppMessageService;
@RestController
@RequestMapping("/appmessage")
public class APPMessageController {
@Autowired
private AppMessageService service;
@RequestMapping("/getThree")
public List<AppMessage> getThreeForMessage(){
List<AppMessage> list = service.getMessage();
return list;
}
@RequestMapping("/getAll")
public List<AppMessage> getAllMessage(){
List<AppMessage> list = service.getAllMessage();
int num = list.size();
if(null!=list && num>3){
for (int i = 0; i < num-3; i++) {
list.remove(0);
}
}
return list;
}
@RequestMapping("/getByID")
public List<AppMessage> getMessageById(@RequestParam("id") String id){
List<AppMessage> list = service.getMessageById(id);
int num = list.size();
if(null!=list && num>5){
for (int i = 0; i < num-5; i++) {
list.remove(0);
}
}
return list;
}
@RequestMapping(value = "/add",method = RequestMethod.POST)
public int addMessage(@RequestBody AppMessage appMessage){
return service.addMessage(appMessage);
}
@RequestMapping(value="/delMessageById")
public int delMessageById(@RequestParam("id") String id){
return service.delMessage(id);
}
}
</pre>
需要注意的地方：
1，bean中需要有无参构造器(如果存在有参构造器，则编译器不会自动添加无参构造器)
第四步，访问
