使用 Spring 的 IOC 实现账户的 CRUD (XML配置)

需求

实现账户的 CRUD 操作

开始编写

导入maven依赖（pom.xml）

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>5.1.47</version>
</dependency>

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context</artifactId>
    <version>5.2.12.RELEASE</version>
</dependency>

<dependency>
    <groupId>commons-dbutils</groupId>
    <artifactId>commons-dbutils</artifactId>
    <version>1.6</version>
</dependency>

<dependency>
    <groupId>com.mchange</groupId>
    <artifactId>c3p0</artifactId>
    <version>0.9.5.2</version>
</dependency>

<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.13.1</version>
</dependency>

<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <version>1.18.16</version>
</dependency>

创建数据库

DROP TABLE IF EXISTS `account`;
CREATE TABLE `account` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(40) DEFAULT NULL,
  `money` float DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8;

INSERT INTO `account` VALUES ('1', 'aaa', '1000');
INSERT INTO `account` VALUES ('2', 'bbb', '1000');
INSERT INTO `account` VALUES ('3', 'ccc', '1000');

编写实体类（cn.imzjw.entity.Account.java）

@Data
@NoArgsConstructor
@AllArgsConstructor
public class Account implements Serializable {

    private Integer id;
    private String name;
    private float money;
}

编写持久层代码（cn.imzjw.dao.IAccountDao.java）

public interface IAccountDao {

    /**
     * 查询所有
     *
     * @return
     */
    List<Account> findAllAccount();

    /**
     * 查询一个
     *
     * @return
     */
    Account findAccountById(Integer id);

    /**
     * 保存账户
     */
    void saveAccount(Account account);

    /**
     * 删除账户
     */
    void delAccount(Integer id);

    /**
     * 更新账户
     */
    void updateAccount(Account account);
}

持久层接口实现类（cn.imzjw.dao.impl.AccountDaoImpl）

public class AccountDaoImpl implements IAccountDao {

    private QueryRunner queryRunner;

    public void setQueryRunner(QueryRunner queryRunner) {
        this.queryRunner = queryRunner;
    }

    @Override
    public List<Account> findAllAccount() {
        try {
            return queryRunner.query("SELECT * FROM account", 
                                     new BeanListHandler<Account>(Account.class));
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return null;
    }

    @Override
    public Account findAccountById(Integer id) {
        try {
            return queryRunner.query("SELECT * FROM account WHERE id = ?", 
                                     new BeanHandler<>(Account.class), id);
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return null;
    }

    @Override
    public void saveAccount(Account account) {
        try {
            queryRunner.update("INSERT INTO account(name, money) VALUES(?, ?)", 
                               account.getName(), account.getMoney());
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void delAccount(Integer id) {
        try {
            queryRunner.update("DELETE FROM account WHERE id = ?", id);
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void updateAccount(Account account) {
        try {
            queryRunner.update("UPDATE account SET name = ?, money = ? WHERE id = ?", 
                               account.getName(), account.getMoney(), account.getId());
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

编写业务层代码（cn.imzjw.service.IAccountService.java）

public interface IAccountService {

    /**
     * 查询所有
     *
     * @return
     */
    List<Account> findAllAccount();

    /**
     * 查询一个
     *
     * @return
     */
    Account findAccountById(Integer id);

    /**
     * 保存账户
     */
    void saveAccount(Account account);

    /**
     * 删除账户
     */
    void delAccount(Integer id);

    /**
     * 更新账户
     */
    void updateAccount(Account account);
}

编写业务层接口实现类（cn.imzjw.service.impl.AccountServiceImpl.java）

public class AccountServiceImpl implements IAccountService {

    private IAccountDao accountDao;

    public void setAccountDao(IAccountDao accountDao) {
        this.accountDao = accountDao;
    }

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

    @Override
    public Account findAccountById(Integer id) {
        return accountDao.findAccountById(id);
    }

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

    @Override
    public void delAccount(Integer id) {
        accountDao.delAccount(id);
    }

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

在resources下new一个xml配置文件，命名随意，但不可中文，配置文件代码如下：

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

    <!--配置 service -->
    <bean id="accountService" class="cn.imzjw.service.impl.AccountServiceImpl">
        <!--注入 accountDao -->
        <property name="accountDao" ref="accountDaoImpl"/>
    </bean>

    <!--配置持久层-->
    <bean id="accountDaoImpl" class="cn.imzjw.dao.impl.AccountDaoImpl">
        <!--注入 queryRunner -->
        <property name="queryRunner" ref="queryRunner"/>
    </bean>

    <!--配置 queryRunner-->
    <bean id="queryRunner" class="org.apache.commons.dbutils.QueryRunner" scope="singleton">
        <!--注入数据源-->
        <constructor-arg name="ds" ref="dataSource"/>
    </bean>

    <!--配置数据源-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <!--连接数据库的必备信息-->
        <property name="driverClass" value="com.mysql.jdbc.Driver"/>
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/spring"/>
        <property name="user" value="garvey"/>
        <property name="password" value="garvey"/>
    </bean>

</beans>

经过如上一番配置，现在开始进行测试

在test包下新建测试类，如图，这是我的项目结构

测试

编写测试类代码（cn.imzjw.test.AccountServiceTest.java）

public class AccountServiceTest {

    /**
     * 获取容器
     *
     * @return 业务层接口
     */
    private IAccountService getApplicationContext() {
        ApplicationContext ac = new ClassPathXmlApplicationContext("bean.xml");
        return ac.getBean("accountService", IAccountService.class);
    }

    @Test
    public void testFindAll() {
        // 获取容器 --> 得到业务层对象 --> 执行方法
        getApplicationContext().findAllAccount().forEach(s -> System.out.println(s));
    }

    @Test
    public void testFindOne() {
        System.out.println(getApplicationContext().findAccountById(1));
    }

    @Test
    public void testSave() {
        getApplicationContext().saveAccount(new Account(null, "fff", 1000f));
        testFindAll();
        System.out.println("---保存成功---");
    }

    @Test
    public void testUpdate() {
        // 先获取要修改 account 的 id
        Account account = getApplicationContext().findAccountById(3);
        // 更新信息
        account.setMoney(1234f);
        // 执行修改
        getApplicationContext().updateAccount(account);
        // 修改完成调用查询所有方法 查看是否修改成功
        testFindAll();
        System.out.println("---修改成功---");
    }

    @Test
    public void testDelete() {
        getApplicationContext().delAccount(4);
        testFindAll();
        System.out.println("---删除成功---");
    }
}

查询所有运行结果为：

1
2
3

Account(id=1, name=aaa, money=1000.0)
Account(id=2, name=bbb, money=1000.0)
Account(id=3, name=ccc, money=1234.0)

查询一个运行结果为：

1	Account(id=1, name=aaa, money=1000.0)

保存账户运行结果为：

Account(id=1, name=aaa, money=1000.0)
Account(id=2, name=bbb, money=1000.0)
Account(id=3, name=ccc, money=1234.0)
Account(id=8, name=ggg, money=1000.0)
---添加成功---

更新账户运行结果为：

Account(id=1, name=aaa, money=1000.0)
Account(id=2, name=bbb, money=1000.0)
Account(id=3, name=ccc, money=1234.0)
Account(id=8, name=ggg, money=1000.0)
---修改成功---

删除账户运行结果为：

Account(id=1, name=aaa, money=1000.0)
Account(id=2, name=bbb, money=1000.0)
Account(id=3, name=ccc, money=1234.0)
---删除成功---