Spring框架--基于IOC的案例

今天我们实现一个小小的IOC的案例，通过spring框架对service层和dao层对象进行管理，c3p0连接池和数据库相连接，通过service对象调用方法实现对数据库的增删改查。

1.首先创建一个数据库，在eesy库下创建一张表account，如图：

2.引入依赖：

<?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">
    <parent>
        <artifactId>SpringTest</artifactId>
        <groupId>com.tulun</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>account_xmlioc</artifactId>
    <packaging>jar</packaging>

    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.1.7.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>commons-dbutils</groupId>
            <artifactId>commons-dbutils</artifactId>
            <version>1.4</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.39</version>
        </dependency>

        <dependency>
            <groupId>c3p0</groupId>
            <artifactId>c3p0</artifactId>
            <version>0.9.1.2</version>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.10</version>
        </dependency>
    </dependencies>
</project>

3.创建一个account类与数据库进行映射：

import java.io.Serializable;

public class Account implements Serializable {
    private Integer id;
    private String name;
    private Float money;

    public Integer getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

    public Float getMoney() {
        return money;
    }

    public void setMoney(Float money) {
        this.money = money;
    }

    @Override
    public String toString() {
        return "Account{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", money=" + money +
                '}';
    }
}

分层结构如图：

4.xml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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">

    <!--配置Service-->
    <bean id="accountService" class="com.service.impl.AccountServiceImpl">
        <!--注入dao-->
        <property name="accountDao" ref="accountDao"></property>

    </bean>

    <!--配置dao对象-->
    <bean id="accountDao" class="com.dao.impl.AccountDaoImpl">
        <!--注入QueryRunner-->
        <property name="runner" ref="runner"></property>
    </bean>


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

    <!--配置数据源-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <!--连接数据库必备信息-->
        <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/eesy"></property>
        <property name="user" value="root"></property>
        <property name="password" value="123"></property>
    </bean>

</beans>

5.账户的持久层实现类

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import java.util.List;

public class AccountDaoImpl implements AccountDao {
    private QueryRunner runner;

    public List<Account> findAllAccount() {
        try {
            return runner.query("select * from account",new BeanListHandler<Account>(Account.class));
        }catch (Exception e){
            throw new RuntimeException(e);
        }
    }

    public Account findAccountById(Integer accountId) {
        try {
            return runner.query("select * from account where id = ?",new BeanHandler<Account>(Account.class),accountId);
        }catch (Exception e){
            throw new RuntimeException(e);
        }
    }

    public void saveAccount(Account account) {
        try {
            runner.update("insert into account(name,money)values(?,?)",account.getName(),account.getMoney());
        }catch (Exception e){
            throw new RuntimeException(e);
        }

    }

    public void updateAccount(Account account) {
        try {
            runner.update("update account set name=?,money=? where id=?",account.getName(),account.getMoney(),account.getId());
        }catch (Exception e){
            throw new RuntimeException(e);
        }
    }

    public void deleteAccount(Integer accountId) {
        try {
            runner.update("delete from account where id=?",accountId);
        }catch (Exception e){
            throw new RuntimeException(e);
        }
    }

    public void setRunner(QueryRunner runner) {
        this.runner = runner;
    }

    public QueryRunner getRunner() {
        return runner;
    }
}

6.账户业务层实现类：

import java.util.List;

public class AccountServiceImpl implements AccountService {
    private AccountDao accountDao;

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

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


    public Account findAccountById(Integer accountId) {
        return accountDao.findAccountById(accountId);
    }

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

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

    public void deleteAccount(Integer accountId) {
        accountDao.deleteAccount(accountId);
    }
}

7.账户的持久层接口：

import java.util.List;

public interface AccountDao {
    /**
     * 查询所有
     * @return
     */
    List<Account> findAllAccount();

    /**
     * 查询一个
     */
    Account findAccountById(Integer accountId);

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

    /**
     * 更新
     */
    void updateAccount(Account account);

    /**
     * 删除
     */
    void deleteAccount(Integer accountId);
}

8.账户业务层接口

import java.util.List;

public interface AccountService {
    /**
     * 查询所有
     * @return
     */
    List<Account> findAllAccount();

    /**
     * 查询一个
     */
    Account findAccountById(Integer accountId);

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

    /**
     * 更新
     */
    void updateAccount(Account account);

    /**
     * 删除
     */
    void deleteAccount(Integer accountId);

}

9.测试类：

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import java.util.List;

/**
 * 描述：使用junit单元测试，测试我们的配置
 */
public class AccountServiceTest {
    @Test
    public void testFindAll() {
        //1.获取容器
        ApplicationContext ac = new ClassPathXmlApplicationContext("bean.xml");
        //2.得到业务层对对象
        AccountService as = ac.getBean("accountService",AccountService.class);
        //3.执行方法
        List<Account> accounts = as.findAllAccount();
        for (Account account : accounts){
            System.out.println(account);
        }
    }

    @Test
    public void testSave() {
        Account account = new Account();
        account.setName("zhangsan");
        account.setMoney(55555f);
        //1.获取容器
        ApplicationContext ac = new ClassPathXmlApplicationContext("bean.xml");
        //2.得到业务层对对象
        AccountService as = ac.getBean("accountService",AccountService.class);
        //3.执行方法
        as.saveAccount(account);
    }
 }

运行结果：

findAllAccount（）

与我们数据库中的是一致的

testSave（）

好了以上我们就通过xml配置形式实现了这个IOC的小小的案例，有兴趣的朋友还可以用注解形式动手自己去实现以下，也是非常的简单。