在applicationContext.xml中配置如下代码
<!--
在spring主配置文件中,告诉spring IOC容器,user在这里,
spring一旦运行起来就会首先加载该配置文件作为spring的上下文
创建user对象(实例)
-->
<bean id="user" class="com.spring.di.User">
<property name="id" value="2"></property>
<property name="username">
<value>marry</value>
</property>
</bean>
<bean id="person" class="com.spring.di.Person">
<property name="name">
<value>zhangsan</value>
</property>
<property name="age" value="32"></property>
<property name="sal" value="3200"></property>
<property name="user">
<ref bean="user"></ref>
</property>
<property name="user2">
<!-- 内部bean 作用范围只在当前person bean 的内部
外部是看不见 不能被外部bean使用
-->
<bean class="com.spring.di.User">
<property name="id" value="22"></property>
<property name="username">
<value>marry2</value>
</property>
</bean>
</property>
</bean>
<bean id="dog" class="com.spring.di.Dog">
<!-- 根据构造器参数的索引来注入 -->
<!-- <constructor-arg value="小花花" index="0"></constructor-arg>
<constructor-arg value="白色" index="1"></constructor-arg> -->
<!-- 根据构造器参数类型注入 -->
<constructor-arg value="小花花" index="0" type="java.lang.String"></constructor-arg>
<constructor-arg value="白色" index="1" type="java.lang.String"></constructor-arg>
<constructor-arg value="1" index="2" type="java.lang.Integer"></constructor-arg>
<constructor-arg type="com.spring.di.User" ref="user"></constructor-arg>
</bean>
<bean id="cat" class="com.spring.di.Cat">
<property name="name" value="詹尼"></property>
<!-- 注入null值 也可以不注入 -->
<property name="color">
<null />
</property>
</bean>
<!-- 集合类型注入 -->
<bean id="pet" class="com.spring.di.Pet">
<!-- List类型注入 -->
<property name="dogs">
<list>
<value>小花花</value>
<value>珍妮</value>
<value>旺财</value>
<value>小强</value>
</list>
</property>
<!-- Set类型注入 -->
<property name="cats">
<set>
<value>小花花</value>
<value>珍妮</value>
<value>旺财</value>
<value>小强</value>
</set>
</property>
<!-- Map类型注入 -->
<property name="pigs">
<map>
<entry>
<key>
<value>1</value>
</key>
<value>大白</value>
</entry>
<entry key="2" value="小白"></entry>
</map>
</property>
<!-- 数组类型注入 -->
<property name="birds">
<list>
<value>新天问</value>
<value>喜鹊</value>
</list>
</property>
<!-- Properties类型属性注入 -->
<property name="pp">
<props>
<prop key="p1">p1_value</prop>
<prop key="p2">p2_value</prop>
</props>
</property>
</bean>
<!-- 自动装配
byName byTime
-->
<bean id="a" class="com.spring.auto.A">
<property name="aname" value="AAA"></property>
</bean>
<bean id="b" class="com.spring.auto.B">
<property name="bname" value="BBB"></property>
</bean>
<!-- 这是正常的对象属性注入 -->
<bean id="ab" class="com.spring.auto.AB">
<property name="a">
<ref bean="a"></ref>
</property>
<property name="b">
<ref bean="b"></ref>
</property>
</bean>
<!-- byName
spring的IOC容器会根据AB类的属性名称会去在容器中自动查找id等于其属性名称的bean进行自动装配(实现注入)
-->
<bean id="ab_byName" class="com.spring.auto.AB" autowire="byName">
</bean>
<!-- byType
spring的IOC容器会根据AB类的属性类型去容器中自动查找类型等同于其属性类型的bean进行自动装配(实现注入)
如果出现了多个类型相同的bean 使用byType自动装配就会出现异常
org.springframework.beans.factory.NoUniqueBeanDefinitionException
-->
<!-- <bean id="b1" class="com.spring.auto.B">
<property name="bname" value="BBB1"></property>
</bean> -->
<bean id="ab_byType" class="com.spring.auto.AB" autowire="byType">
</bean>
<!-- 分散装配
org.springframework.beans.factory.config.PropertyPlaceholderConfigurer
-->
<bean id="propertyPlaceholderConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="location">
<value>test.properties</value>
</property>
</bean>
test.propertie文件
key1=value1
key2=value2
key3=value3
<bean id="testProperties" class="com.spring.auto.TestProperties">
<property name="key1" value="${key1}"></property>
<property name="key2" value="${key2}"></property>
<property name="key3" value="${key3}"></property>
</bean>
测试代码如下
ApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext.xml");
/*AB ab= (AB) ac.getBean("ab");
System.out.println(ab);*/
AB ab_byName= (AB) ac.getBean("ab_byName");
System.out.println(ab_byName);
/* AB ab_byType= (AB) ac.getBean("ab_byType");
System.out.println(ab_byType);*/
/*TestProperties testProperties= (TestProperties) ac.getBean("testProperties");
System.out.println(testProperties);*/
/* User user = new User(); //代码的耦合在一起,不利于后期代码的维护
user.setUsername("jack");
System.out.println(user.toString());
System.out.println("------------------------");
User user2 = new User(1,"tom","123");
System.out.println(user2.toString());*/
//启动spring的IOC容器 加载主配置文件
/* @SuppressWarnings("resource")
ApplicationContext ac= new ClassPathXmlApplicationContext("applicationContext.xml");
User user =(User) ac.getBean("user");
System.out.println(user.toString());*/
ApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext.xml");
Person person = (Person) ac.getBean("person");
System.out.println(person.toString());
/*Cat cat=(Cat) ac.getBean("cat");
System.out.println(cat);*/
/*Pet pet= (Pet) ac.getBean("pet");
System.out.println(pet);*/
时间： 2024-10-14 03:54:33