SpringBoot入门之SpringBoot整合SpringDataJPA 05

爱被打了一巴掌 2021-11-09 03:31 490阅读 0赞

# 5. SpringBoot整合SpringDataJpa #

## 5.1 先在数据库中创建库和表 ##

CREATE DATABASE B;
    USE B;
    DROP TABLE IF EXISTS `user`;
    CREATE TABLE `user` (
     `id` bigint(20) NOT NULL AUTO_INCREMENT,
     `user_name` varchar(100) DEFAULT NULL COMMENT '用户名',
     `password` varchar(100) DEFAULT NULL COMMENT '密码',
     `name` varchar(100) DEFAULT NULL COMMENT '姓名',
     PRIMARY KEY (`id`)
    ) ENGINE=InnoDB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8;
    INSERT INTO `user` VALUES ('1', 'zhangsan', '123456', '张三');
    INSERT INTO `user` VALUES ('2', 'lisi', '123456', '李四');
    INSERT INTO `user` VALUES ('3', 'wangwu', '123456', '王五');
    INSERT INTO `user` VALUES ('4', 'zhangwei', '123456', '张伟');
    INSERT INTO `user` VALUES ('5', 'lina', '123456', '李娜');
    INSERT INTO `user` VALUES ('6', 'lilei', '123456', '李磊');

## 5.2 pom文件中导入mysql和springdataJpa启动器 ##

<dependency>
          <groupId>mysql</groupId>
       	  <artifactId>mysql-connector-java</artifactId>
    </dependency>
    
    
    <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-data-jpa</artifactId>
    </dependency>

## 5.3 项目src下resources创建application.properties ##

![在这里插入图片描述][20190804192950186.png]  
**注意必须命名为application.properties**, 否则SpringBoot不认识这个配置文件.

spring.datasource.driverClassName=com.mysql.jdbc.Driver
    spring.datasource.url=jdbc:mysql://127.0.0.1:3306/b?useUnicode=true&characterEncoding=utf8&autoReconnect=true&allowMultiQueries=true
    spring.datasource.username=root
    spring.datasource.password=root
    
    # JPA Configuration
    spring.jpa.database=mysql
    spring.jpa.show-sql=true
    spring.jpa.generate-ddl=true
    spring.jpa.hibernate.ddl-auto=update

## 5.4 编写代码 ##

1.  com.acece包下创建一个domain包, 包下编写一个**User**实体类

package com.acece.domain;
    import javax.persistence.*;
    import java.io.Serializable;
    @Entity
    @Table(name = "user")
    public class User implements Serializable{ 
    
        @Id
        @Column(name = "id")
        @GeneratedValue(strategy = GenerationType.IDENTITY)
        private Integer userId;
        @Column(name = "user_name")
        private String userName;
        @Column(name = "password")
        private String password;
        @Column(name = "name")
        private String name;
    
    
        public Integer getUserId() { 
            return userId;
        }
    
        public void setUserId(Integer userId) { 
            this.userId = userId;
        }
    
        public String getUserName() { 
            return userName;
        }
    
        public void setUserName(String userName) { 
            this.userName = userName;
        }
    
        public String getPassword() { 
            return password;
        }
    
        public void setPassword(String password) { 
            this.password = password;
        }
    
        public String getName() { 
            return name;
        }
    
        public void setName(String name) { 
            this.name = name;
        }
    
        @Override
        public String toString() { 
            return "User{" +
                    "userId=" + userId +
                    ", userName='" + userName + '\'' +
                    ", password='" + password + '\'' +
                    ", name='" + name + '\'' +
                    '}';
        }
    }

1.  com.acece包下创建dao包,编写**UserDao**接口

package com.acece.dao;
    import com.acece.domain.User;
    import org.springframework.data.jpa.repository.JpaRepository;
    import java.util.List;
    
    public interface UserDao extends JpaRepository<User,Integer>{ 
    }

1.  com.acece包下创建service包,编写**UserService**接口

package com.acece.service;
    
    import com.acece.domain.User;
    
    import java.util.List;
    
    /** * */
    public interface UserService { 
    
        List<User> findAll();
    }

1.  com.acece.service包下创建impl包,包下编写**UserServieImpl**实体类

package com.acece.service.impl;
    
    import com.acece.dao.UserDao;
    import com.acece.domain.User;
    import com.acece.service.UserService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Service;
    
    import java.util.List;
    
    /** * */
    @Service
    public class UserServiceImpl implements UserService { 
    
        @Autowired
        private UserDao userDao;
    
        @Override
        public List<User> findAll() { 
            return userDao.findAll();
        }
    }

1.  com.acece包下创建controller包,编写**UserController**类

package com.acece.controller;
    
    
    import com.acece.domain.User;
    import com.acece.service.UserService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    import java.util.List;
    
    /** * */
    @RestController
    @RequestMapping("/user")
    public class UserController { 
    
        @Autowired
        private UserService userService;
    
        @RequestMapping("/findAll")
        public List<User> findAll(){ 
            return userService.findAll();
        }
    }

## 5.5 启动项目,访问localhost:8080/user/findAll ##

能够查出数据,至此**SpringBoot整合SpringDataJpa完成~**  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjY0MTkwOQ_size_16_color_FFFFFF_t_70]

[20190804192950186.png]: /images/20211109/61b4beb4cc2d4ac39dd3932ec8afcce2.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjY0MTkwOQ_size_16_color_FFFFFF_t_70]: /images/20211109/81b90cbace38422abcaa181673019add.png