Spring boot集成spring-boot-starter-data-jpa环境搭建

Posted 2020-11-09 Kevin00

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1、创建Spring boot项目

2、保存等待构建完成

3、增加spring-boot-starter-data-jpa、内存数据库依赖包hsqldb

        <!-- 添加data jpa依赖 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>

        <dependency>
            <groupId>org.hsqldb</groupId>
            <artifactId>hsqldb</artifactId>
            <scope>runtime</scope>
        </dependency>

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>

    <groupId>com.kevin</groupId>
    <artifactId>boot</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>boot</name>
    <description>Demo project for Spring Boot</description>

    <!--
   spring-boot-starter-parent项目中继承以获得合理的默认值。父项目提供以下功能：
   Java 1.8作为默认的编译器级别。
   UTF-8源码编码。
   一个依赖管理部分，从春天启动依赖性继承POM，管理公共依赖的版本。这种依赖关系管理可以让您在自己的pom中使用这些依赖关系时忽略<version>标记。
   明智的 资源过滤。
   明智的插件配置（exec插件， Git提交ID和 阴影）。
   明智的资源过滤application.properties和application.yml 包括配置文件特定的文件（例如application-dev.properties和 application-dev.yml）-->

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.2.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>

        <!-- 添加data jpa依赖 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>

        <dependency>
            <groupId>org.hsqldb</groupId>
            <artifactId>hsqldb</artifactId>
            <scope>runtime</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>


</project>

4、项目结构图

5、相关文件

applicationContext.properties

ddl-auto:create----每次运行该程序，没有表格会新建表格，表内有数据会清空

ddl-auto:create-drop----每次程序结束的时候会清空表

ddl-auto:update----每次运行程序，没有表格会新建表格，表内有数据不会清空，只会更新

ddl-auto:validate----运行程序会校验数据与数据库的字段类型是否相同，不同会报错

spring.jpa.hibernate.ddl-auto = create-drop

实体类User.java

package com.kevin.boot.model;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import java.io.Serializable;

/**
 * @author pingan.yang
 * @program SpringBootJpa
 * @description
 * @create 2018-05-29 19:10
 */
@Entity
public class User implements Serializable {
    @Id
    @GeneratedValue
    private int id;

    @Column(nullable = false)
    private String name;

    @Column(nullable = false)
    private int age;

    public User() {

    }

    public User (String name, int age) {
        this.name = name;
        this.age = 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;
    }
}

数据库底层操作类UserRepository.java

package com.kevin.boot.repository;

import com.kevin.boot.model.User;
import org.springframework.data.jpa.repository.JpaRepository;

import java.util.List;

public interface UserRepository extends JpaRepository<User, Long> {

    User getUserById(int id);

    List<User> getUserByName(String name);

}

User业务中心控制类

package com.kevin.boot.controller;

import com.kevin.boot.model.User;
import com.kevin.boot.repository.UserRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

/**
 * @author kevin.yang
 * @program SpringBootJpa
 * @description
 * @create 2018-05-29 19:11
 */
// RestController = Controller + ResponseBody
@RestController
public class UserController {

    @Autowired
    private UserRepository userRepository;

    @RequestMapping("/saveUser")
    public String saveUser(@RequestParam("name") String name, @RequestParam("age") int age) {
        try {
            User user = new User(name, age);
            userRepository.save(user);
        } catch (Exception e) {
            e.printStackTrace();
            return "error";
        }

        return "save success";
    }

    @RequestMapping("/getUserById")
    public User getUserById(@RequestParam("id") int id) {
        return userRepository.getUserById(id);
    }

    @RequestMapping("/getAllUser")
    public List<User> getAllUser() {
        return userRepository.findAll();
    }
}