利用Spring的IOC的实现数据库的CRUD

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发布于 2020-02-12 15:10:10

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发布于 2020-02-12 15:10:10

文章被收录于专栏：墨白的Java基地

正文

引言:

纵然是基础,也还是有很多人不会;

打开你的图形化界面工具(sqlyog,navicat...),创建数据库spring-test,导入以下SQL

DROP TABLE IF EXISTS USER;

CREATE TABLE USER (
  id INT(11) NOT NULL AUTO_INCREMENT,
  username VARCHAR(32) NOT NULL COMMENT '用户名称',
  birthday DATETIME DEFAULT NULL COMMENT '生日',
  sex CHAR(1) DEFAULT NULL COMMENT '性别',
  address VARCHAR(256) DEFAULT NULL COMMENT '地址',
  PRIMARY KEY  (id)
) ENGINE=INNODB DEFAULT CHARSET=utf8;

INSERT  INTO USER(id,username,birthday,sex,address) VALUES (41,'老王','2018-02-27 17:47:08','男','北京'),(42,'小二王','2018-03-02 15:09:37','女','鼓岭'),(43,'小二王','2018-03-04 11:34:34','女','东京'),(45,'南京','2018-03-04 12:04:06','男','北京金燕龙'),(46,'老王','2018-03-07 17:37:26','男','北京'),(48,'小马宝莉','2018-03-08 11:44:00','女','北京修正');


DROP TABLE IF EXISTS account;
CREATE TABLE account (
  accountId INT(11) NOT NULL AUTO_INCREMENT,
  UID INT(11) DEFAULT NULL COMMENT '用户编号',
  MONEY DOUBLE DEFAULT NULL COMMENT '金额',
  PRIMARY KEY  (accountId),
  KEY FK_Reference_8 (UID),
  CONSTRAINT FK_Reference_8 FOREIGN KEY (UID) REFERENCES USER (id)
) ENGINE=INNODB DEFAULT CHARSET=utf8;

INSERT  INTO account(accountId,UID,MONEY) VALUES (1,46,1000),(2,45,1000),(3,46,2000);

效果图如下:

打开你的IDEA,创建maven项目,导入相关坐标

<?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.mobaijun</groupId>
    <artifactId>spring_test</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <!-- mysql驱动 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.46</version>
        </dependency>
        <!-- 数据源 -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.6</version>
        </dependency>
        <!-- Spring的JdbcTemplate -->
        <dependency> 
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.0.2.RELEASE</version>
        </dependency>
        <!-- spring的IOC -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.0.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.10</version>
        </dependency>
    </dependencies>
</project>

编写Account实体

/**
 * DevelopmentTool: IntelliJ IDEA 2018.2.4 x64
 * Author: Auser·杰
 * CreateDate:  2020/1/6 0:09
 * 释义: 账户实体类
 */
@Data
public class Account implements Serializable{

    private int accountId;
    
    private int uid;
    
    private double money;

编写Dao/(Mapper)接口和实现

/**
 * DevelopmentTool: IntelliJ IDEA 2018.2.4 x64
 * Author: Auser·杰
 * CreateDate: 2020/1/26 0:56
 * ClassName: AccountDao
 * 释义:accountDao接口
 */
public interface AccountDao {
    
    public void save(Account account);
    
    public void update(Account account);
    
    public void delete(int accountId);
    
    public List<Account> findAll();
    
}

编写Dao实现

/**
 * DevelopmentTool: IntelliJ IDEA 2018.2.4 x64
 * Author: Auser·杰
 * CreateDate: 2020/1/26 0:56
 * ClassName: AccountDaoImpl
 * 释义:AccountDaoImpl实现
 */
public class AccountDaoImpl implements AccountDao {

    //需要JdbcTemplate对象（使用IOC容器创建）
    private JdbcTemplate jdbcTemplate;

    //提供setter，以便IOC进行依赖注入
    public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
        this.jdbcTemplate = jdbcTemplate;
    }

    @Override
    public void save(Account account) {
        jdbcTemplate.update("insert into account(uid,money) values(?,?)"
                ,account.getUid(),account.getMoney());
    }

    @Override
    public void update(Account account) {
        jdbcTemplate.update("update account set uid=?,money=? where accountId=?",
                account.getUid(),account.getMoney(),account.getAccountId());
    }

    @Override
    public void delete(int accountId) {
        jdbcTemplate.update("delete from account where accountId = ?",accountId);
    }

    @Override
    public List<Account> findAll() {
        return jdbcTemplate.query("select * from account",new BeanPropertyRowMapper<>(Account.class));
    }
}

编写Service接口

/**
 * DevelopmentTool: IntelliJ IDEA 2018.2.4 x64
 * Author: Auser·杰
 * CreateDate: 2020/1/26 0:56
 * ClassName: AccountService
 * 释义:AccountService实现
 */
public interface AccountService {

    public void save(Account account);

    public void update(Account account);

    public void delete(int accountId);

    public List<Account> findAll();
}

编写Service实现

/**
 * DevelopmentTool: IntelliJ IDEA 2018.2.4 x64
 * Author: Auser·杰
 * CreateDate: 2020/1/26 0:56
 * ClassName: BaseController
 * 释义:账户Service实现
 */
public class AccountServiceImpl implements AccountService{
    
    //需要AccountDao对象（使用IOC进行注入）
    private AccountDao accountDao;

    //给IOC进行依赖注入的方法
    public void setAccountDao(AccountDao accountDao) {
        this.accountDao = accountDao;
    }

    @Override
    public void save(Account account) {
        accountDao.save(account);
    }

    @Override
    public void update(Account account) {
        accountDao.update(account);
    }

    @Override
    public void delete(int accountId) {
        accountDao.delete(accountId);
    }

    @Override
    public List<Account> findAll() {
        return accountDao.findAll();
    }
}

配置数据库资源文件

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/spring_test?characterEncoding=utf-8
jdbc.username=xxxxxx
jdbc.password=xxxxxxx

编写IOC配置文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd">

    <!-- 读取jdbc.properties文件 -->
    <!--
       classpath:  从类路径下面开始加载
    -->
    <context:property-placeholder location="classpath:jdbc.properties"/>

    <!-- 1. 创建数据源对象 -->
    <!--
     DruidDataSource ds = new DruidDataSource()
     ds.setUrl(xxx);
     ....
       -->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
        <property name="url" value="${jdbc.url}"/>
        <property name="driverClassName" value="${jdbc.driver}"/>
        <property name="username" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
    </bean>

    <!-- 2. 创建JdbcTemplate对象，同时注入数据源 -->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
       <!-- <constructor-arg ref="dataSource"/>-->
        
        <property name="dataSource" ref="dataSource"/>
    </bean>

    <!-- 3. 创建Dao对象，同时注入JdbcTemplate对象 -->
    <bean id="accountDao" class="com.mobaijun.dao.impl.AccountDaoImpl">
        <property name="jdbcTemplate" ref="jdbcTemplate"/>
    </bean>
    
    <!-- 4. 创建Service对象，同时注入Dao对象 -->
    <bean id="accountService" class="com.mobaijun.service.impl.AccountServiceImpl">
        <property name="accountDao" ref="accountDao"/>
    </bean>
</beans>

/**
 * DevelopmentTool: IntelliJ IDEA 2018.2.4 x64
 * Author: Auser·杰
 * CreateDate: 2020/1/26 0:56
 * ClassName: AccountServiceTest
 * 释义:测试类
 */
public class AccountServiceTest {

    @Test
    public void testFindAll(){
        //1.创建IOC容器
        ApplicationContext ac = new ClassPathXmlApplicationContext("spring/applicationContext.xml");
        //2.获取service对象
        AccountService accountService = (AccountService)ac.getBean("accountService");
             List<Account> list = accountService.findAll();
        for(Account account:list){
            System.out.println(account);
        }
    }

}