Spring-Data-Jpa
JPA(Java Persistence API)定义了一系列对象持久化的标准,目前实现这一规范的产品有hibernate、TopLink等
JPA
application.yml:
spring:
profiles:
active: prod
datasource:
driver-class-name: com.mysql.jdbc.driver
url: jdbc:mysql://127.0.0.1:3306/dbgirl
username: root
password: 123456
jpa:
hibernate:
ddl-auto: create
show-sql: true
注意:ddl-auto中的属性:
create:在每次程序启动的时候都会重新创建一次表,之前的数据会被清空
update:第一次运行时会创建对应的表结构,如果里面有数据,会保留
create-drop:应用停止时,会把表删除
none:什么都不做
validate:验证类中的属性与表结构是否一致,不一致则报错
新建一个类Girl:
package com.hcx;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
/**
* Created by HCX on 2017/8/15.
*/
@Entity //该注解表示该类在数据库中有对应的表 不用创建该表
public class Girl {
@Id
@GeneratedValue
private Integer id;
private String cupSize;
private Integer age;
public Girl() {
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getCupSize() {
return cupSize;
}
public void setCupSize(String cupSize) {
this.cupSize = cupSize;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
}
例:
application.yml:
spring:
profiles:
active: prod
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://127.0.0.1:3306/dbgirl
username: root
password: 123456
jpa:
hibernate:
ddl-auto: create
show-sql: true
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>
<!--项目的基本描述-->
<groupId>com.hcx</groupId>
<artifactId>girl</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>girl</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.6.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>
<!--web项目必须引入的依赖-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!--单元测试时需要用到的-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</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>
GirlRepository:
package com.hcx;
import org.springframework.data.jpa.repository.JpaRepository;
import java.util.List;
/**
* Created by HCX on 2017/8/15.
*/
public interface GirlRepository extends JpaRepository<Girl,Integer> {
/**JpaRepository<>
* 第一个泛型:类名
* 第二个泛型:id的类型
*/
//通过年龄来查询
public List<Girl> findByAge(Integer age);
}
GirlController:
package com.hcx;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.DeleteMapping;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.PutMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
/**
* Created by HCX on 2017/8/15.
*/
@RestController
public class GirlController {
@Autowired
private GirlRepository girlRepository;
/**
* 查询所有女生
* @return
*/
@GetMapping(value = "/girls")
public List<Girl> girlList(){
return girlRepository.findAll();
}
/**
* 添加一个女生
* @param cupSize
* @param age
* @return
*/
@PostMapping(value="/girls")
public Girl girlAdd(@RequestParam("cupSize") String cupSize,
@RequestParam("age") Integer age){
Girl girl = new Girl();
girl.setCupSize(cupSize);
girl.setAge(age);
return girlRepository.save(girl);
}
/**
* 查询一个女生
* @param id
* @return
*/
@GetMapping(value = "/girls/{id}") //访问:127.0.0.1:8080/girls/2
public Girl girlFindOne(@PathVariable("id") Integer id){
return girlRepository.findOne(id);
}
/**
* 通过年龄查询女生列表
* @param age
* @return
*/
@GetMapping(value = "/girls/age/{age}")
public List<Girl> girlListByAge(@PathVariable("age") Integer age){
return girlRepository.findByAge(age);
}
/**
* 更新
* @param id
* @param cupSize
* @param age
* @return
*/
@PutMapping(value = "girls/{id}")
public Girl girlUpdate(@PathVariable("id") Integer id,
@RequestParam("cupSize") String cupSize,
@RequestParam("age") Integer age){
Girl girl = new Girl();
girl.setId(id);
girl.setCupSize(cupSize);
girl.setAge(age);
return girlRepository.save(girl);//根据数据库字段的值,如果id设置为主键,则根据主键来更新
}
/**
* 删除
* @param id
*/
@DeleteMapping(value = "/girls/{id}")
public void girlDelete(@PathVariable("id") Integer id){
girlRepository.delete(id);
}
}