spring bean与local之区别

Spring中的ref属性指定依赖的3种方式2008-07-09 10:16Spring中，ref属性有三种指定依赖的方式，分别时：local,bean,parent.

下面分别看一下代码：

Java代码

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE beans Public "-//SPRING//DTD BEAN//EN"

"http://www.springframework.org/dtd/spring-beans.dtd">

<beans>

<bean id ="HelloWorld" class="com.jnotnull.HelloWorld" depends="date">

<property name ="message">

<value>HelloWorld</value>

</property>

<property name ="date">

<ref local="date">

</property>

<bean>

<bean id="date" class="java.util.Date">

</beans>

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE beans Public "-//SPRING//DTD BEAN//EN"

"http://www.springframework.org/dtd/spring-beans.dtd">

<beans>

<bean id ="HelloWorld" class="com.jnotnull.HelloWorld" depends="date">

<property name ="message">

<value>HelloWorld</value>

</property>

<property name ="date">

<ref local="date">

</property>

<bean>

<bean id="date" class="java.util.Date">

</beans>

Java代码

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE beans Public "-//SPRING//DTD BEAN//EN"

"http://www.springframework.org/dtd/spring-beans.dtd">

<beans>

<bean id ="HelloWorld" class="com.jnotnull.HelloWorld" depends="date">

<property name ="message">

<value>HelloWorld</value>

</property>

<property name ="date">

<ref bean="date">

</property>

<bean>

<bean id="date" class="java.util.Date">

</beans>

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE beans Public "-//SPRING//DTD BEAN//EN"

"http://www.springframework.org/dtd/spring-beans.dtd">

<beans>

<bean id ="HelloWorld" class="com.jnotnull.HelloWorld" depends="date">

<property name ="message">

<value>HelloWorld</value>

</property>

<property name ="date">

<ref bean="date">

</property>

<bean>

<bean id="date" class="java.util.Date">

</beans>

Java代码

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE beans Public "-//SPRING//DTD BEAN//EN"

"http://www.springframework.org/dtd/spring-beans.dtd">

<beans>

<bean id ="HelloWorld" class="com.jnotnull.HelloWorld" depends="date">

<property name ="message">

<value>HelloWorld</value>

</property>

<property name ="date">

<ref parent="date">

</property>

<bean>

<bean id="date" class="java.util.Date">

</beans>

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE beans Public "-//SPRING//DTD BEAN//EN"

"http://www.springframework.org/dtd/spring-beans.dtd">

<beans>

<bean id ="HelloWorld" class="com.jnotnull.HelloWorld" depends="date">

<property name ="message">

<value>HelloWorld</value>

</property>

<property name ="date">

<ref parent="date">

</property>

<bean>

<bean id="date" class="java.util.Date">

</beans>

下面看看它们之间的区别：

local用于本地，即同文档中的bean

bean可以跨xml文档，同时bean属性的值可以和依赖的Bean的id属性相同，也可以和name属性相同。

parent:容许应用当前BeanFactory或ApplicationContext的父BeanFactory或者ApplicationContext中的Bean,同时bean属性的值可以和依赖的Bean的id属性相同，也可以和name属性相同。