Inheritance in Spring

Inheritance Demo, In the example given below we are going to tell about the inheritance in the Spring framework. By inheritance we mean a way of forming new classes using classes that have already been defined. Here we have created a simple bean and used this bean as a template for creating other beans.

:-Creates a Parent bean which would be used as a template for creating other beans. Here "mybean" is the name of the bean class which would be referred in the xml file with the id "parent".

:-Creates a child bean which would be inheriting from the parent bean defined above.

parent="parent":-Specify that this bean is inheriting the properties of some other bean.

context.xml

"1.0" encoding="UTF-8"?> "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"> "parent" class="mybean" > "name" value="Roseindia.net"/> "child" class="mybean" parent="parent"> "address" value="Rohini"/> "subchild" class="mybean" parent="parent"/>

Main.java

This is the file through which we are retrieving the property of the bean defined above. Some of the methods which are used here are as follows:-

XmlBeanFactory factory = new XmlBeanFactory(new ClassPathResource("context.xml")):-This method creates an instance of the XmlBeanFactory which is used to read bean definition from an XML document

new ClassPathResource("context.xml"):-Creates a new ClassPathResource for ClassLoader .Here the context.xml is the file which is to be loaded.

(bf.getBean("child")):-This method returns an instance of the bean named "child", which is shared or independent, of the given bean name.

(bf.getBean("subchild")):-This method returns an instance of the bean named "subchild", which is shared or independent, of the given bean name.

stringBuilder.append("Bean"):-This is the method of the class string Builder which appends the specified string to this character sequence.

import org.springframework.beans.factory.xml.XmlBeanFactory; import org.springframework.core.io.ClassPathResource; public class Main { public static void main(String[] args) throws Exception { XmlBeanFactory bf = new XmlBeanFactory(new ClassPathResource("context.xml")); System.out.println("===============Inheritance demo================="); System.out.println(bf.getBean("child")); System.out.println(bf.getBean("subchild")); } } class mybean { private String name; private String address; public void setName(String name) { this.name = name; } public void setAddress(String address) { this.address = address; } @Override public String toString() { final StringBuilder stringBuilder = new StringBuilder(); stringBuilder.append("Bean"); stringBuilder.append("{name='").append(name).append('\''); stringBuilder.append(", address=").append(address); stringBuilder.append('}'); return stringBuilder.toString(); } }

Output of the program

Nov 25, 2008 3:39:29 AM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions INFO: Loading XML bean definitions from class path resource [context.xml] ===============Inheritance demo================= Bean{name='Roseindia.net', address=Rohini} Bean{name='Roseindia.net', address=null} BUILD SUCCESSFUL (total time: 1 second)

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