Spring Collection Merging
In this tutorial you will see an example of spring collection merging.
In this tutorial you will see an example of spring collection merging.
Spring Collection Merging
The merging of collection is allowed in the Spring 2.0. A parent-style like
<list/>, <map/>, <set/> or <pros/> element can have child-style <list/>, <map/>,
<set/> or <pros/> element which inherit and overrides the values from the parent
collection. For collection merging you need to specify merge=true attribute on
the <props/> element of child bean definition. Note you cannot merge Map
and List collection type.
CollegeBean.java
package collection.merge.example;
import java.util.Properties;
public class CollegeBean {
private Properties pros;
public Properties getPros() {
return pros;
}
public void setPros(Properties pros) {
this.pros = pros;
}
@Override
public String toString() {
return "College [Props=" + pros + "]";
}
}
|
ProsMain.java
package collection.merge.example;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class PropsMain {
public static void main(String[] args) {
BeanFactory beanfactory = new ClassPathXmlApplicationContext(
"context.xml");
CollegeBean coll = (CollegeBean) beanfactory.getBean("child");
System.out.println(coll);
}
}
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context.xml
<bean id="parent" abstract="true"
class="collection.merge.example.CollegeBean">
<property name="pros">
<props>
<prop key="Year">25</prop>
<prop key="NickName">Raj</prop>
</props>
</property>
</bean>
<bean id="child" parent="parent" >
<property name="pros">
<props merge="true">
<prop key="Roll">101</prop>
<prop key="Name">Rohit Raj</prop>
</props>
</property>
</bean>
</beans>
|
When you run this application it will display output as shown below:
| College [Props={Name=Rohit Raj, Roll=101, Year=25,
NickName=Raj}] |
Download this example code
