Spring Boot Mysql 資料庫操作

本文預設你的開發環境.資料庫已經安裝好

想用使用資料庫.我們需要現在pom檔案中添加相應的依賴

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.imgod</groupId>
	<artifactId>testjpa</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>war</packaging>

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

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.4.2.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-data-jpa</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-tomcat</artifactId>
			<scope>provided</scope>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-jdbc</artifactId>
		</dependency>
		<!-- 添加Hibernate依賴 -->
		<dependency>
			<groupId>org.hibernate</groupId>
			<artifactId>hibernate-core</artifactId>
		</dependency>
	</dependencies>

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


</project>
           

我們的配置檔案進行資料庫的配置

application.properties:

spring.datasource.url=jdbc:mysql://127.0.0.1:3306/test
spring.datasource.username=root
spring.datasource.password=imgod1
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.max-idle=10
spring.datasource.max-wait=10000
spring.datasource.min-idle=5
spring.datasource.initial-size=5
spring.jpa.properties.hibernate.hbm2ddl.auto=update
           

前面配置的是資料庫資訊,最後一行配置的是.如果我們定義的實體在資料庫中沒有對應的表的話.會幫我們自動建立

我們的實體類型

User.java

package com.imgod.bean;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
import javax.validation.constraints.NotNull;

@Entity
@Table(name = "users")
public class User {
	@Id
	@GeneratedValue(strategy = GenerationType.AUTO)
	private int id;
	@NotNull
	private String email;
	@NotNull
	private String name;

	public int getId() {
		return id;
	}

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

	public String getEmail() {
		return email;
	}

	public void setEmail(String email) {
		this.email = email;
	}

	public String getName() {
		return name;
	}

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

}
           

對應資料庫中的user表,沒有的話會自動建立

想對資料庫進行操作,我們需要建立一個接口繼承CrudRepository

UserDao.java

package com.imgod.dao;

import org.springframework.data.domain.Pageable;
import org.springframework.data.repository.CrudRepository;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;

import com.imgod.bean.User;
import java.lang.String;
import java.util.List;

@Transactional
@Repository
public interface UserDao extends CrudRepository<User, Integer> {
	//jpa 方法名就是查詢語句,隻要規法寫方法名一切就都可以完成(當然.有時候會造成方法名又臭又長)
	User findByEmail(String email);//根據郵箱查詢
	List<User> findByName(String name);//根據使用者名查詢
	
	//select * from test.users where email='[email protected]' and name='imgod';
	List<User> findByNameAndEmail(String name,String email);//根據使用者名和郵箱進行查詢
	
	//select * from test.users where email='[email protected]' and name='imgod4444' order by id desc;
	List<User> findByNameAndEmailOrderByIdDesc(String name,String email);//根據使用者名和郵箱進行查詢,排序
	
	//select * from test.users where email='[email protected]' and name='imgod4444' order by id desc limit 2;
	List<User> findTop2ByNameAndEmailOrderByIdDesc(String name,String email);//根據使用者名和郵箱進行查詢,排序,前兩個

	//根據郵箱進行分頁查詢
	List<User> findByEmail(String email,Pageable pageable);//根據使用者名和郵箱進行查詢
}
           

實作CrudRepository我們就可以對資料庫進行一些基礎操作了

如果我們想要實作更多的操作.需要自己按照嚴格的命名規則為方法定義方法名

下面就是我們重要的控制器的實作了:

package com.imgod.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.PageRequest;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.imgod.bean.User;
import com.imgod.dao.UserDao;

@RestController
public class UserController {
	@Autowired
	private UserDao userDao;

	/**
	 * 根據郵件去查找
	 * 
	 * @param email
	 * @return
	 */
	@RequestMapping(value = "/findUserByEmail")
	public Object getUserByEmail(String email) {
		System.out.println("email:" + email);
		User user = userDao.findByEmail(email);
		if (null == user) {
			return "暫無資料";
		} else {
			return user;
		}

	}

	/**
	 * 擷取所有的使用者資訊
	 * 
	 * @return
	 */
	@RequestMapping(value = "/getall")
	public Object getAllUser() {
		List<User> list = (List<User>) userDao.findAll();
		if (null == list || list.size() == 0) {
			return "暫無資料";
		} else {
			return list;
		}

	}

	/**
	 * 删除指定id使用者
	 * 
	 * @param id
	 * @return
	 */
	@RequestMapping(value = "/deleteUser")
	public Object deleteuUser(int id) {
		User user = userDao.findOne(id);
		if (null == user) {
			return "删除使用者失敗:" + id + "沒找到該使用者";
		} else {
			userDao.delete(id);
			return "删除使用者成功:" + id;
		}

	}

	/**
	 * 添加使用者
	 * 
	 * @param id
	 * @param email
	 * @param name
	 * @return
	 */
	@RequestMapping(value = "/adduser")
	public Object addUser(String id, String email, String name) {
		System.out.println("email:" + email);

		int tempId = Integer.parseInt(id);
		System.out.println("tempId:" + tempId + "email:" + email + "name:" + name);

		User tempUser = userDao.findOne(tempId);
		if (null == tempUser) {
			tempUser = new User();
			tempUser.setId(tempId);
		}
		tempUser.setEmail(email);
		tempUser.setName(name);
		User resultUser = userDao.save(tempUser);
		if (null == resultUser) {
			return "新增使用者失敗";
		} else {
			return "新增使用者:" + resultUser.getName();
		}

	}

	// 條件查詢

	/**
	 * 擷取姓名和郵箱是指定内容的使用者
	 * 
	 * @return
	 */
	@RequestMapping(value = "/getUser1")
	public Object getUser(String email, String name) {
		List<User> userList = userDao.findByNameAndEmail(name, email);
		if (null != userList && userList.size() != 0) {
			return userList;
		} else {
			return "沒找到符合要求的使用者";
		}

	}

	/**
	 * 擷取姓名和郵箱是指定内容的使用者并排序
	 * 
	 * @return
	 */
	@RequestMapping(value = "/getUser2")
	public Object getUser2(String email, String name) {
		List<User> userList = userDao.findByNameAndEmailOrderByIdDesc(name, email);
		if (null != userList && userList.size() != 0) {
			return userList;
		} else {
			return "沒找到符合要求的使用者";
		}

	}

	/**
	 * 擷取姓名和郵箱是指定内容的使用者并排序,前兩個
	 * 
	 * @return
	 */
	@RequestMapping(value = "/getUser3")
	public Object getUser3(String email, String name) {
		List<User> userList = userDao.findTop2ByNameAndEmailOrderByIdDesc(name, email);
		if (null != userList && userList.size() != 0) {
			return userList;
		} else {
			return "沒找到符合要求的使用者";
		}

	}

	/**
	 * 分頁擷取郵箱為指定内容的資料
	 * 
	 * @return
	 */
	@RequestMapping(value = "/getUser4")
	public Object getUser4(String email, int page) {
		// page 屬于下标 從0開始 0代表是第一頁
		List<User> userList = userDao.findByEmail(email, new PageRequest(page, 2));
		if (null != userList && userList.size() != 0) {
			return userList;
		} else {
			return "沒找到符合要求的使用者";
		}

	}
}
           

如此我們就完成了對資料庫的操作:

完整代碼位址:http://download.csdn.net/download/u010399316/9698797