学习 Spring (二) Spring 注入
Spring入门篇 学习笔记
常用的两种注入方式
- 设值注入
- 构造注入
示例准备工作
添加 InjectionDAO：
public interface InjectionDAO {
void save(String arg);
}
添加 InjectionDAOImpl：
public class InjectionDAOImpl implements InjectionDAO {
public void save(String arg) {
System.out.println("保存数据：" + arg);
}
}
添加 InjectionService：
public interface InjectionService {
void save(String arg);
}
设值注入
添加 InjectionServicePropertyImpl：
public class InjectionServicePropertyImpl implements InjectionService {
private InjectionDAO injectionDAO;
public void setInjectionDAO(InjectionDAO injectionDAO) {
this.injectionDAO = injectionDAO;
}
public void save(String arg) {
System.out.println("Service(Property)接收参数：" + arg);
arg = arg + ":" + this.hashCode();
injectionDAO.save(arg);
}
}
添加配置文件 classpath:spring-injection-property.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" >
<bean id="injectionService" class="com.karonda.ioc.injection.service.InjectionServicePropertyImpl">
<property name="injectionDAO" ref="injectionDAO"></property>
</bean>
<bean id="injectionDAO" class="com.karonda.ioc.injection.dao.InjectionDAOImpl"></bean>
</beans>
添加测试 TestInjectionProperty：
@RunWith(BlockJUnit4ClassRunner.class)
public class TestInjectionProperty extends UnitTestBase {
public TestInjectionProperty() {
super("classpath:spring-injection-property.xml");
}
@Test
public void testSetter() {
InjectionService service = super.getBean("injectionService");
service.save("这是要保存的数据");
}
}
构造注入
添加 InjectionServiceConstructorImpl：
public class InjectionServiceConstructorImpl implements InjectionService {
private InjectionDAO injectionDAO;
//构造器注入
public InjectionServiceConstructorImpl(InjectionDAO injectionDAO) {
this.injectionDAO = injectionDAO;
}
public void save(String arg) {
//模拟业务操作
System.out.println("Service(Constructor)接收参数：" + arg);
arg = arg + ":" + this.hashCode();
injectionDAO.save(arg);
}
}
添加配置文件 spring-injection-constructor.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" >
<bean id="injectionService" class="com.karonda.ioc.injection.service.InjectionServiceConstructorImpl">
<constructor-arg name="injectionDAO" ref="injectionDAO"></constructor-arg>
</bean>
<bean id="injectionDAO" class="com.karonda.ioc.injection.dao.InjectionDAOImpl"></bean>
</beans>
添加测试 TestInjectionConstructor
@RunWith(BlockJUnit4ClassRunner.class)
public class TestInjectionConstructor extends UnitTestBase {
public TestInjectionConstructor() {
super("classpath:spring-injection-constructor.xml");
}
@Test
public void testCons() {
InjectionService service = super.getBean("injectionService");
service.save("这是要保存的数据");
}
}
