Spring bean definition template

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As we discussed earlier a bean definition in configuration metadata can contain constructor arguments, property values etc. Spring framework provides the facility to define a bean definition template which can be used by child bean definitions. To define a template remove class attribute and use abstract attribute to true in bean definition.
Use parent attribute in child definition and pass template bean into it.

Syntax:

Note: We can create template with or without using the class attribute. If we create template using class attribute then corresponding class can’t be instantiated.

Example Explanation:

We have created two beans “HelloWorld” and “HelloJava”. HelloWorld.java and HelloJava.java have one common property msg1. In applicationContext.xml we defined a template helloTemplate which define msg1 property. Then HelloJava and HelloWorld bean use this template as parent and inherits the msg1 property.

Example:

HelloWorld.java

package com.w3schools360.business;

/**
 * This class will be used as a bean class.
 * @author W3schools360
 */
public class HelloWorld {
	private String msg1;
	private String msg2;
	
	public String getMsg1() {
		return msg1;
	}
	public void setMsg1(String msg1) {
		this.msg1 = msg1;
	}
	
	public String getMsg2() {
		return msg2;
	}
	public void setMsg2(String msg2) {
		this.msg2 = msg2;
	}	
}

HelloJava.java

package com.w3schools360.business;

/**
 * This class will be used as a bean class.
 * @author W3schools360
 */
public class HelloJava {
	private String msg1;
	private String msg2;
	
	public String getMsg1() {
		return msg1;
	}
	public void setMsg1(String msg1) {
		this.msg1 = msg1;
	}
	
	public String getMsg2() {
		return msg2;
	}
	public void setMsg2(String msg2) {
		this.msg2 = msg2;
	}
		
}

applicationContext.java

Test.java

package com.w3schools360.business;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Test {
  public static void main(String[] args) {
	//Get ApplicationContext using spring configuration file.
	ApplicationContext context = 
	   new ClassPathXmlApplicationContext("applicationContext.xml");
		
	//Get HelloWorld bean object from ApplicationContext instance. 
	HelloWorld helloWorld = (HelloWorld) context.getBean("helloWorld");
		
	//Process HelloWorld Object.
	System.out.println("HelloWorld bean properties: ");
	System.out.println("Hello " + helloWorld.getMsg1());
	System.out.println("Hello " + helloWorld.getMsg2());
		
	//Get HelloJava bean object from ApplicationContext instance. 
	HelloJava helloJava = (HelloJava) context.getBean("helloJava");
		
	//Process HelloJava Object.
	System.out.println("HelloJava bean properties: ");
	System.out.println("Hello " + helloJava.getMsg1());
	System.out.println("Hello " + helloJava.getMsg2());
  } 
}

Output:

HelloWorld bean properties: 
Hello Common World.
Hello World.
HelloJava bean properties: 
Hello Common World.
Hello Java

 
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