springboot之整合jpa

最新推荐文章于 2023-07-22 21:44:15 发布

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最新推荐文章于 2023-07-22 21:44:15 发布

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分类专栏： java 文章标签： springboot

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本文介绍了一个使用SpringBoot结合JPA进行数据库操作的具体案例，包括项目搭建步骤、依赖引入、配置文件设置、实体类定义、DAO层实现、Service层接口及实现、Controller层RESTful风格API设计等内容。

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本文展示一个springboot通过jpa查询数据库的例子, springboot版本 1.5.9

首先引入依赖

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

然后在application.properties中添加mysql相关的配置

spring.datasource.url=jdbc:mysql://localhost:3306/test
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driverClassName=com.mysql.jdbc.Driver
# Specify the DBMS
spring.jpa.database = MYSQL
# Show or not log for each sql query
spring.jpa.show-sql = true
# Hibernate ddl auto (create, create-drop, update)
spring.jpa.hibernate.ddl-auto = update
# Naming strategy
spring.jpa.hibernate.naming-strategy = org.hibernate.cfg.ImprovedNamingStrategy
# stripped before adding them to the entity manager)
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect

model类

package com.bus365.root.model;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name = "user")
public class User {
	@Id
	@GeneratedValue(strategy = GenerationType.AUTO)
	private Long id;
	private String name;
	private Integer age;
	private Integer addressid;
	public Long getId() {
		return id;
	}
	public void setId(Long id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public Integer getAge() {
		return age;
	}
	public void setAge(Integer age) {
		this.age = age;
	}
	public Integer getAddressid() {
		return addressid;
	}
	public void setAddressid(Integer addressid) {
		this.addressid = addressid;
	}
	@Override
	public String toString() {
		return "User [id=" + id + ", name=" + name + ", age=" + age + ", addressid=" + addressid + "]";
	}
		
}

controller层,使用restful风格路由

package com.bus365.root.controller;

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

import com.bus365.root.model.User;
import com.bus365.root.service.UserService;

@RestController
public class UserController {
	@Autowired
	private UserService userService;

	@RequestMapping(value = "/user", method = { RequestMethod.PUT })
	public String adduser(User user) {
		String result = userService.add(user);
		return result;
	}
	@RequestMapping(value = "/user", method = { RequestMethod.GET })
	public String finduser(Long id) {
		String find = userService.find(id);
		return find;
	}
	@RequestMapping(value = "/user", method = { RequestMethod.POST })
	public String updateuser(User user) {
		String update = userService.update(user);
		return update;
	}
	@RequestMapping(value = "/user", method = { RequestMethod.DELETE })
	public String deleteuser(Long id) {
		String delete = userService.delete(id);
		return delete;
	}
}

持久化dao层的UserDao类

package com.bus365.root.dao;


import java.io.Serializable;
import java.util.List;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.query.Param;

import com.bus365.root.model.User;

public interface UserDao extends JpaRepository<User,Long>,JpaSpecificationExecutor<User>,Serializable {
	
	@Query(value = "from User where name = :name")
	List<User> findbyname(@Param("name") String name);
}

Service层

package com.bus365.root.service;

import com.bus365.root.model.User;

public interface UserService {
	public String add(User user);

	public String find(Long id);

	public String delete(Long id);

	public String update(User user); 
	
}

package com.bus365.root.service.impl;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.bus365.root.Constants;
import com.bus365.root.dao.UserDao;
import com.bus365.root.model.User;
import com.bus365.root.service.UserService;

@Service
public class UserServiceImpl implements UserService {
	@Autowired
	private UserDao userDao;

	public String add(User user) {
		User findOne = null;
		try {
			findOne = userDao.findOne(user.getId());
		} catch (Exception e) {
		}
		if(findOne!=null) {
			return Constants.FAIL;
		}
		try {
			userDao.save(user);
		} catch (Exception e) {
			return Constants.FAIL;
		}
		return Constants.SUCCESS;
	}

	@Override
	public String find(Long id) {
		try {
			userDao.findOne(id);
		} catch (Exception e) {
			return Constants.FAIL;
		}
		return Constants.SUCCESS;
	}

	@Override
	public String delete(Long id) {
		try {
			userDao.delete(id);
		} catch (Exception e) {
			return Constants.FAIL;
		}
		return Constants.SUCCESS;
	}

	@Override
	public String update(User user) {
		try {
			userDao.save(user);
		} catch (Exception e) {
			return Constants.FAIL;
		}
		return Constants.SUCCESS;
	}

}

github项目地址 https://github.com/Christain1993/SpringBootIntegration