【Spring】IOC案例从XML到注解

• 本例不展示业务代码。仅展示跟spring的使用相关的代码。

基于XML的IOC案例

• service 实现类

public class AccountServiceImpl implements AccountService {
private AccountDao accountDao;
public void setAccountDao(AccountDao accountDao) {
this.accountDao = accountDao;
}
}

• dao 实现类

public class AccountDaoImpl implements AccountDao {
private QueryRunner runner ;
public void setRunner(QueryRunner runner) {
this.runner = runner;
}
}

• spring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">

<bean id="accountService" class="com.wei.service.impl.AccountServiceImpl" >
<property name="accountDao" ref="accountDao" />
</bean>

<bean id="accountDao" class="com.wei.dao.impl.AccountDaoImpl" >
<!--根据set方法名决定-->
<property name="Runner" ref="queryRunner" />
</bean>

<bean id="queryRunner" class="org.apache.commons.dbutils.QueryRunner" scope="prototype" >
<!--因为源码是ds，所以只能写ds-->
<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 name="jdbcUrl" value="jdbc:mysql://localhost:3306/spring" />
<property name="user" value="root" />
<property name="password" value="root" />
</bean>
</beans>

基于注解的IOC案例

• 需要导入context名称空间。上例XML已经加入了。后面我删除了bean.xml，仍然可以运行。混合使用的话，就需要spring配置文件，所以还是留着吧！

• service / dao 接口 实体类

public interface AccountService {
//业务代码
}
public interface AccountDao {
//业务代码
}
@Data
public class Account implements Serializable {
//字段
}

• service / dao 实现类

@Service("accountService")
public class AccountServiceImpl implements AccountService {
@Autowired
private AccountDao accountDao;
//业务代码
}

@Repository("accountDao")
public class AccountDaoImpl implements AccountDao {
@Autowired
private QueryRunner runner ;
//业务代码
}

• config 类， 主配置类、子配置类、jdbcConfig.properties

@Configuration
@ComponentScan(basePackages = "com.wei")
@Import({JdbcConfig.class})
@PropertySource("classpath:jdbcConfig.properties")
public class SpringConfiguration {
}

@Configuration
public class JdbcConfig {
//需要读取配置文件，读取的注解在主配置文件上（PropertySource）
@Value("${jdbc.driver}")
private String driver;
@Value("${jdbc.url}")
private String url;
@Value("${jdbc.username}")
private String username;
@Value("${jdbc.password}")
private String password;

@Bean(name = "runner")
public QueryRunner createQueryRunner(@Qualifier("dataSource") DataSource dataSource){
return new QueryRunner(dataSource);
}
@Bean("dataSource")
@Scope("prototype")
public DataSource createDataSource(){
ComboPooledDataSource ds = new ComboPooledDataSource();
ds.setDriverClass(driver);ds.setJdbcUrl(url);ds.setUser(username);ds.setPassword(password);
return ds;
}
}

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/spring
jdbc.username=root
jdbc.password=root

Spring 整合 Junit

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration( classes = SpringConfiguration.class)
public class Client {
@Autowired
private AccountService accountService;

@Test
public void findAll(){
List<Account> all = accountService.findAll();
System.out.println(all);
}
}

pow.xml

<packaging>jar</packaging>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>5.2.7.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>5.2.7.RELEASE</version>
</dependency>
<dependency>
<groupId>javax.annotation</groupId>
<artifactId>javax.annotation-api</artifactId>
<version>1.3.2</version>
</dependency>
<dependency>
<groupId>commons-dbutils</groupId>
<artifactId>commons-dbutils</artifactId>
<version>1.7</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.40</version>
</dependency>
<dependency>
<groupId>c3p0</groupId>
<artifactId>c3p0</artifactId>
<version>0.9.1.1</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
</dependencies>