Spring_boot搭配Spring Data JPA简单操作数据库
spring boot 配置文件可以使用yml文件,默认spring boot 会加载resources目录的下的application.yml文件,yml文件严格使用tab缩进。
pom.xml
<dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.11</version> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> <version>1.5.7.RELEASE</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> <version>1.5.7.RELEASE</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.6</version> </dependency> <dependency> <groupId>javax.persistence</groupId> <artifactId>persistence-api</artifactId> <version>1.0</version> </dependency> <dependency> <artifactId>slf4j-api</artifactId> <groupId>org.slf4j</groupId> <version>1.7.10</version> </dependency> <dependency> <groupId>ch.qos.logback</groupId> <artifactId>logback-classic</artifactId> <version>1.2.3</version> <exclusions> <exclusion> <artifactId>slf4j-api</artifactId> <groupId>org.slf4j</groupId> </exclusion> </exclusions> </dependency> <dependency> <groupId>ch.qos.logback</groupId> <artifactId>logback-core</artifactId> <version>1.2.3</version> </dependency> </dependencies>
application.yml 配置文件 链接数据库
spring:
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://127.0.0.1:3306/njy
username: root
password: root
jpa:
hibernate:
ddl-auto: update #create删除表再创建 update 保存原来数据
show-sql: true
对于数据库的操作有点类似mabatis的mapper接口代理,需要自定义一个接口继承JpaRepository
package ni.jun.yang; import ni.jun.yang.bean.Girl; import org.springframework.data.jpa.repository.JpaRepository; public interface GirlRepository extends JpaRepository<Girl, Integer>{ }
Contrller中实现逻辑
package ni.jun.yang; import ni.jun.yang.bean.Girl; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.RestController; import java.util.List; @RestController public class GirlController { @Autowired private GirlRepository girlRepository; @GetMapping(value = "/girls") public List<Girl> selectAll(){ return girlRepository.findAll(); } @GetMapping(value = "/addGirls") public Girl selectAll(@RequestParam String name, @RequestParam Integer age){ Girl girl = new Girl(); girl.setAge(age); girl.setName(name); return girlRepository.save(girl); } }
启动服务之后发送http://localhost:8080/addGirls?name=aaa&age=18请求会发现数据插入一条数据,http://localhost:8080/girls会将数据库中数据查询出来,修改也是调用save方法,删除delete方法,查询一个findOne。通过其他字段查询需要去自定义接口添加抽象方法findByxxx,xxx为字段名字。复杂查询百度
查找maven依赖:http://mvnrepository.com/ 尽量使用发布时间相近的包,避免不兼容问题