SpringBoot+JPA简单入门demo

港控/mmm° 2021-09-27 07:08 597阅读 0赞

**1.创建一个普通的maven工程**

**2.配置pom.xml**

<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.xiao</groupId>  
  <artifactId>SpringBootJPA</artifactId>  
  <version>0.0.1-SNAPSHOT</version>  
  <packaging>jar</packaging>  
  <name>SpringBootJPA</name>  
  <url>http://maven.apache.org</url>

<properties>  
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>  
  </properties>  
    
    
    <parent>  
        <groupId>org.springframework.boot</groupId>  
        <artifactId>spring-boot-starter-parent</artifactId>  
        <version>1.5.6.RELEASE</version>  
    </parent>  
      
  <dependencies>  
      
        <dependency>  
            <groupId>org.springframework.boot</groupId>  
            <artifactId>spring-boot-starter-web</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>  
          
        <dependency>  
            <groupId>org.springframework.boot</groupId>  
            <artifactId>spring-boot-configuration-processor</artifactId>  
            <optional>true</optional>  
        </dependency>  
  </dependencies>  
    
  <build>  
        <plugins>  
            <plugin>  
                <groupId>org.springframework.boot</groupId>  
                <artifactId>spring-boot-maven-plugin</artifactId>  
            </plugin>  
        </plugins>  
    </build>  
</project>  
**3.配置数据源。在src/main/resources下新建一个application.properties文件**

\# 服务器访问端口  
server.port=8080  
\# 数据库基本配置  
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/springbootjpa  
spring.datasource.username=root  
spring.datasource.password=root  
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

spring.jpa.database=MYSQL  
\# 显示后台处理的SQL语句  
spring.jpa.show-sql=true  
\# 自动检查实体和数据库表是否一致，如果不一致则会进行更新数据库表  
spring.jpa.hibernate.ddl-auto=update

**4.配置应用程序启动类，Application.java**

package com.xiao.SpringBootJPA;

import org.springframework.boot.SpringApplication;  
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;  
import org.springframework.boot.web.servlet.ServletComponentScan;  
import org.springframework.context.annotation.ComponentScan;  
import org.springframework.scheduling.annotation.EnableScheduling;  
import org.springframework.transaction.annotation.EnableTransactionManagement;

/\*\*  
 \* SpringBootJpa应用程序启动文件  
\* @author xiaosongsong:   
\* @CreateTime 创建时间：2018年8月10日 下午9:21:23   
\* 类说明  
 \*/  
@EnableAutoConfiguration  
@EnableTransactionManagement  
@ServletComponentScan  
@ComponentScan  
@EnableScheduling  
public class Application    
\{  
    public static void main( String\[\] args )  
    \{  
        System.out.println( "Hello World!" );  
        SpringApplication.run(Application.class, args);  
    \}  
\}  
**5.创建实体Employee.java**

package com.xiao.SpringBootJPA.entity;

import java.io.Serializable;

import javax.persistence.Column;  
import javax.persistence.Entity;  
import javax.persistence.Id;  
import javax.persistence.Table;

/\*\*  
 \* 职工类  
\* @author xiaosongsong:   
\* @CreateTime 创建时间：2018年8月10日 下午9:23:58   
\* 类说明  
 \*/  
@Entity  
@Table(name="employee")  
public class Employee implements Serializable \{

private static final long serialVersionUID = -2544247758732046249L;

@Id  
    @Column(name="id")  
    private String id;  
      
    @Column(name="name")  
    private String name;  
      
    @Column(name="gender")  
    private String gender;  
      
    @Column(name="age")  
    private int age;

public String getId() \{  
        return id;  
    \}

public void setId(String id) \{  
        this.id = id;  
    \}

public String getName() \{  
        return name;  
    \}

public void setName(String name) \{  
        this.name = name;  
    \}

public String getGender() \{  
        return gender;  
    \}

public void setGender(String gender) \{  
        this.gender = gender;  
    \}

public int getAge() \{  
        return age;  
    \}

public void setAge(int age) \{  
        this.age = age;  
    \}  
      
      
\}  
**6.创建repository接口**

package com.xiao.SpringBootJPA.repository;

import org.springframework.data.jpa.repository.JpaRepository;  
import org.springframework.stereotype.Repository;

import com.xiao.SpringBootJPA.entity.Employee;

/\*\*  
 \* EmployeeRepository接口  
\* @author xiaosongsong:   
\* @CreateTime 创建时间：2018年8月10日 下午9:27:08   
\* 类说明  
 \*/  
@Repository  
public interface EmployeeRepository extends JpaRepository<Employee, String>\{

\}  
**7.创建控制层**

package com.xiao.SpringBootJPA.controller;

import java.util.ArrayList;  
import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;  
import org.springframework.web.bind.annotation.RequestMapping;  
import org.springframework.web.bind.annotation.ResponseBody;  
import org.springframework.web.bind.annotation.RestController;

import com.xiao.SpringBootJPA.entity.Employee;  
import com.xiao.SpringBootJPA.repository.EmployeeRepository;

/\*\*  
 \* 职工Controller  
\* @author xiaosongsong:   
\* @CreateTime 创建时间：2018年8月10日 下午9:30:30   
\* 类说明  
 \*/  
@RestController  
@RequestMapping("/employee")  
public class EmployeeController \{  
      
    @Autowired  
    private EmployeeRepository employeeRepository;

@RequestMapping("/queryAll")  
    @ResponseBody  
    public List<Employee> queryAll()\{  
        List<Employee> list=new ArrayList<Employee>();  
        list=employeeRepository.findAll();  
        return list;  
    \}  
      
\}  
**8.启动应用程序，访问[http://localhost:8080/employee/queryAll][http_localhost_8080_employee_queryAll]**

![70][]

[http_localhost_8080_employee_queryAll]: http://localhost:8080/employee/queryAll
[70]: /images/20210923/871ab96953a2442094f17e9b72a20426.png