使用idea + maven + +Spring Boot + mysql + MyBatis 快速搭建起SSM框架(SpringBoot 入門案例)
阿新 • • 發佈:2019-02-17
1.首先開啟idea開發工具,然後File->New->Project ,如下圖,下一步
預設配置,下一步
勾選以下三項,下一步
輸入專案名稱,Finish。。然後靜靜等待專案載入完成。。。
載入完成後生成如下目錄,其中DemoApplication是程式入口(我不知道這麼形容準不準確)
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新建包和類,注意,新建的包要跟DemoApplication為同級目錄!!!原因的話自己百度去
User.java
package com.example.demo.domain; /** * 使用者實體類 */ public class User { private int id; private String name; private int age; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } @Override public String toString() { return "User{" + "id=" + id + ", name='" + name + '\'' + ", age=" + age + '}'; } }
UserMapper.xml
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" > <mapper namespace="com.example.demo.dao.UserDao" > <select id="findUserById" resultType="com.example.demo.domain.User"> SELECT * FROM user WHERE id = #{id} </select> </mapper>
UserDao.java
package com.example.demo.dao;
import com.example.demo.domain.User;
import org.apache.ibatis.annotations.Mapper;
/**
* 使用者Dao介面
* */
//@Repository
@Mapper
public interface UserDao {
User findUserById(int id);
}
UserService.java
package com.example.demo.service; import com.example.demo.dao.UserDao; import com.example.demo.domain.User; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; @Service public class UserService { @Autowired private UserDao userdao; public User findUserById(int id) { User user = userdao.findUserById(id); return user; } }
UserCpntroller.java
package com.example.demo.controller;
import com.example.demo.domain.User;
import com.example.demo.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class UserController {
@Autowired
private UserService userService;
@RequestMapping("/find")
public User find () {
User user = userService.findUserById(2);
System.out.print(user);
return user;//返回的是json格式的資料
}
}
修改配置檔案application.properties
#資料連線
spring.datasource.url=jdbc:mysql://localhost:3306/mybatis?useUnicode=true&characterEncoding=utf8
spring.datasource.username=root
spring.datasource.password=546784
spring.datasource.driverClassName=com.mysql.jdbc.Driver
#Mybatis掃描
mybatis.mapper-locations=classpath*:mapper/*.xml
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以上就是全部程式碼,是不是幾乎完全沒有看到配置檔案?這就是SpringBoot厲害的地方了,下面執行專案
執行結果:
(備註:資料庫那邊要自己建
)
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以上就是全部程式碼了。。。歡迎高手指教