Spring（4）使用 Spring的IoC的实现增删该查
一、环境搭建
1.项目构建，我们在原来的基础上修改即可。
修改maven工程的pom文件，添加必须的引用：
<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.xhbjava</groupId> <artifactId>Spring02</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>Spring02</name> <url>http://maven.apache.org</url> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> </properties> <dependencies> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>5.0.2.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>5.0.2.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>8.0.19</version> </dependency> <dependency> <groupId>c3p0</groupId> <artifactId>c3p0</artifactId> <version>0.9.1.2</version> </dependency> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.12</version> </dependency> </dependencies> </project>
2.数据库建表
create table account( id int primary key auto_increment, name varchar(40), money float )
3.编写实体类
package com.xhbjava.pojo; import java.io.Serializable; import java.util.Arrays; import java.util.List; import java.util.Map; import java.util.Properties; import java.util.Set; public class Account implements Serializable { private Integer id; private String name; private Float mmoney; 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 getMmoney() { return mmoney; } public void setMmoney(Float mmoney) { this.mmoney = mmoney; } }
4.编写持久层代码
package com.xhbjava.dao; import java.util.List; import com.xhbjava.pojo.Account; /** * 账户持久层接口 * * @author mr.wang * */ public interface IAccoutDao { /** * 保存账户 */ void saveAccount(Account account); /** * 更新账户 * @param account */ void updateAccount(Account account); /** * 删除账户 * @param accountId */ void deleteAccount(Integer accountId); /** * 根据id查询账户 * * @param accountId * @return */ Account findById(Integer accountId); /** * 查询所有账户 * @return */ List<Account> findAll(); }
package com.xhbjava.dao.impl; import java.util.List; import org.apache.commons.dbutils.QueryRunner; import org.apache.commons.dbutils.handlers.BeanHandler; import org.apache.commons.dbutils.handlers.BeanListHandler; import com.xhbjava.dao.IAccountDao; import com.xhbjava.pojo.Account; /** * 用户持久层接口实现类 * * @author mr.wang * */ public class AccountDaoImpl implements IAccountDao { private QueryRunner runner; public void setRunner(QueryRunner runner) { this.runner = runner; } @Override public void saveAccount(Account account) { try { runner.update("insert into account(name,money)values(?,?)", account.getName(), account.getMmoney()); } catch (Exception e) { throw new RuntimeException(e); } } @Override public void updateAccount(Account account) { try { runner.update("update account set name=?,money=? where id=?", account.getName(), account.getMmoney(), account.getId()); } catch (Exception e) { throw new RuntimeException(e); } } @Override public void deleteAccount(Integer accountId) { try { runner.update("delete from account where id=?", accountId); } catch (Exception e) { throw new RuntimeException(e); } } @Override public Account findById(Integer accountId) { try { return runner.query("select * from account where id=?", new BeanHandler<Account>(Account.class), accountId); } catch (Exception e) { throw new RuntimeException(e); } } @Override public List<Account> findAll() { try { return runner.query("select * from account", new BeanListHandler<Account>(Account.class)); } catch (Exception e) { throw new RuntimeException(e); } } }
5.编写业务层代码
package com.xhbjava.service; import java.util.List; import com.xhbjava.pojo.Account; /** * 账户的业务层接口 * * @author mr.wang * */ public interface IAccountService { /** * 保存账户 */ void saveAccount(Account account); /** * 更新账户 * @param account */ void updateAccount(Account account); /** * 删除账户 * @param accountId */ void deleteAccount(Integer accountId); /** * 根据id查询账户 * * @param accountId * @return */ Account findById(Integer accountId); /** * 查询所有账户 * @return */ List<Account> findAll(); }
package com.xhbjava.service.impl; import java.util.List; import com.xhbjava.dao.IAccountDao; import com.xhbjava.pojo.Account; import com.xhbjava.service.IAccountService; /** * 账户业务层接口实现类 * * @author mr.wang * */ public class AccountServiceImpl implements IAccountService { // 此处依赖有待解决 private IAccountDao accountDao; public void setAccountDao(IAccountDao accountDao) { this.accountDao = accountDao; } @Override public void saveAccount(Account account) { accountDao.saveAccount(account); } @Override public void updateAccount(Account account) { accountDao.updateAccount(account); } @Override public void deleteAccount(Integer accountId) { accountDao.deleteAccount(accountId); } @Override public Account findById(Integer accountId) { return accountDao.findById(accountId); } @Override public List<Account> findAll() { return accountDao.findAll(); } }
6.修改bean.xml
<?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="com.xhbjava.service.impl.AccountServiceImpl"> <property name="accountDao" ref="accountDao"></property> </bean> <!-- 配置dao --> <bean id="accountDao" class="com.xhbjava.dao.impl.AccountDaoImpl"> <property name="runner" ref="runner"></property> </bean> <bean id="runner" class="org.apache.commons.dbutils.QueryRunner" scope="prototype"> <constructor-arg name="ds" ref="dataSource" /> </bean> <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <property name="driverClass" value="com.mysql.jdbc.Driver"></property> <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/ssm?useSSL=true&serverTimezone=UTC&characterEncoding=UTF-8" /> <property name="user" value="root"></property> <property name="password" value="root"></property> </bean> </beans>
二、测试
1.编写测试类
package com.xhbjava.test; import org.junit.Test; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import com.xhbjava.pojo.Account; import com.xhbjava.service.IAccountService; public class testSpring { @Test public void testSaveAccount() { //1.使用ApplicationContest接口获取srping容器 ApplicationContext ac = new ClassPathXmlApplicationContext("bean.xml"); //2.根据beanid获取对象 IAccountService accountService = (IAccountService) ac.getBean("accountService"); Account account = new Account(); account.setName("张三"); account.setMmoney(3232.90f); accountService.saveAccount(account); } @Test public void testUpdateAccount() { //1.使用ApplicationContest接口获取srping容器 ApplicationContext ac = new ClassPathXmlApplicationContext("bean.xml"); //2.根据beanid获取对象 IAccountService accountService = (IAccountService) ac.getBean("accountService"); Account account = new Account(); account.setName("张三"); account.setMmoney(5000f); accountService.updateAccount(account); } }
2.测试
3.发现的问题
通过上面的测试类可以看出我们的每个测试方法都重新获取了一次 spring 的核心容器，造成了不必要的重复，增加了工作量。可能我们会想到直接在测试类new一个容器类，这样的话需要我们自己写代码来获取容器。能不能测试时直接就编写测试方法，而不需要手动编码来获取容器呢？答案是肯定的。我们在下面的章节中介绍。
