Spring继承注入与加载多个配置文件

一.Spring继承(parent)注入

1.抽象继承类使用 abstract="true"

2.子类继承 parent="父类Id"

二.Spring中引用对象方式:

1. local:在当Xml文件中查找对象

<property name="student3">

<ref local="student3" />

</property>

2. bean:在所有的Xml文件中查找对象

spring 默认使用bean方式

bean有两种方式

方式一：

<property name="student3">

<ref bean="student3" />

</property>

方式二：

<property name="student3" ref="student3"/>

3. parent：在父对象中查找

三.使用容器加载多个配置文件

(1)数组方式：

new ClassPathXmlApplicationContext(new String[] {"applicationContext.xml", "".... });

(2)通配符(*)

new ClassPathXmlApplicationContext("applicationContext*.xml"});

注意：配置文件命名统一

例：名字都是以applicationContext开头

applicationContext.xml(通用配置)

applicationContext-web.xml

applicationContext-biz.xml

applicationContext-dao.xml

举例：

Student1{studentId,studentName,password}

Student2{studentId,studentName}

Student3{address}

Student4{student2,student3}

两个配置文件

applicationContext.xml中

<!-- 公共类必须定义成 abstract="true",让子类继承parent="student" -->
<bean id="student" abstract="true">
<property name="studentId" value="1" />
<property name="studentName" value="老赵" />
</bean>

<bean id="student2" class="com.tarena.entity.Student2" parent="student" />

applicationContext-bean.xml中

<bean id="student1" class="com.tarena.entity.Student1" parent="student">
<property name="password" value="123456" />
</bean>

<bean id="student3" class="com.tarena.entity.Student3">
<property name="address" value="北京海淀" />
</bean>
<bean id="student4" class="com.tarena.entity.Student4">
<property name="student2">
<!-- 在当前xml文件中找对象 -->
<ref bean="student2" />
</property>
<!--<property name="student3">
<ref local="student3" />
</property>
-->
<property name="student3" ref="student3"/>
</bean>

测试类：

public class StudetTest {
private static Log log = LogFactory.getLog(StudetTest.class);
private ApplicationContext ac;

@Before
public void setUp() {
// ac =new ClassPathXmlApplicationContext("applicationContext.xml");
/*ac = new ClassPathXmlApplicationContext(new String[] {
"applicationContext.xml", "applicationContext-bean.xml" });*/
ac = new ClassPathXmlApplicationContext("applicationContext*.xml");
}

@Test
@Ignore
public void testStudent1() {
Student1 student = (Student1) ac.getBean("student1");
log.info(student.getPassword());
log.info(student.getStudentId());
log.info(student.getStudentName());
}

@Test
@Ignore
public void testStudent2() {
Student2 student = (Student2) ac.getBean("student2");
log.info(student.getStudentId());
log.info(student.getStudentName());
}

@Test
@Ignore
public void testStudent3() {
Student3 student = (Student3) ac.getBean("student3");
log.info(student.getAddress());
}

@Test
//@Ignore
public void testStudent4() {
Student4 student4 = (Student4) ac.getBean("student4");
log.info(student4.getStudent2().getStudentId());
log.info(student4.getStudent2().getStudentName());
log.info(student4.getStudent3().getAddress());
}
}