Spring Bean Scoops

Spring support 5 types of bean scoops

1. Singleton : singleton scope will return same object reference if you call multiple time to the bean from the IOC Container.
2. Prototype  : It will return new object reference of the bean for every request we do with IOC  Container.
3. Request : Return single bean instance per HTTP request.
4. Session  : Return single bean instance per HTTP Session
5. Global session : Returns single bean instance per HTTP Global Session.
6. Application(V4.0): 

 Example of Singleton Scope: 

import com.javacontainer.service.customer;

public class CustomerService 

{

String message;

public String getMessage() {

return message;

}

public void setMessage(String message) {

this.message = message;

}

}

Bean Configuration in Configuration xml file

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-2.5.xsd">

       

            class="com.javacontainer.service.customer.CustomerService" />

Calling the Bean

package com.javacontainer.common;

import org.springframework.context.ApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.javacontainer.service.customer.CustomerService;

public class App 

{

    public static void main( String[] args )

    {

    ApplicationContext context = 

    new ClassPathXmlApplicationContext(new String[] {"Spring-Customer.xml"});

    CustomerService custA = (CustomerService)context.getBean("customerService");

    custA.setMessage("Message by custA");

    System.out.println("Message : " + custA.getMessage());

   

    //retrieve it again

    CustomerService custB = (CustomerService)context.getBean("customerService");

    System.out.println("Message : " + custB.getMessage());

    }

}

OutPut:

 Message : Message by custA

 Message : Message by custA

Example of Prototype Scope of Bean Configuration

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-2.5.xsd">

       

            class="com.javacontainer.service.customer.CustomerService"  scope="prototype"/>

OutPut

Message : Message by custA

Message : null

Bean Scope Configuration using Annotation :

package com.javacontainer.service.customer.CustomerService;

import org.springframework.context.annotation.Scope;

import org.springframework.stereotype.Service;

@Service

@Scope("prototype")

public class CustomerService 

{

String message;

public String getMessage() {

return message;

}

public void setMessage(String message) {

this.message = message;

}

}

To Read the annotation by the IOC Container we need to configure the element inside the spring configuration file :

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xmlns:context="http://www.springframework.org/schema/context"

xsi:schemaLocation="http://www.springframework.org/schema/beans

http://www.springframework.org/schema/beans/spring-beans-2.5.xsd

http://www.springframework.org/schema/context

http://www.springframework.org/schema/context/spring-context-2.5.xsd">