Spring bean thread scope

 How beans are defined in the IoC container ?

Spring uses the notion of bean scopes to answer to this question .

we have 6 scopes : 

  >singleton, prototype, thread ,request, session, and globalSession . 

the new Scope in the Spring 3.0 is thread . 
Note: Singleton, prototype ,request, session, and globalSession Scopes are explained in this tutorial.

Thread Scope  Utility : 

>it Creates a bean instance per thread. Similar to request scope.

Thread Scope VS Request Scope:

>Thread Scope is available to all context implemenetation scope .

>Request Scope is available only to application contexts (web-freindly)

Note : Thread Scope requires registration with the CustomScopeConfigurer bean.

Illustration of Thread Scope Behavior :

1.Create Maven Project : 

2.Edit pom.xml file & add Spring 3 Dependencies : 

 <properties>

    <spring.version>3.0.5.RELEASE</spring.version>

  </properties>



  <dependencies>

    <!-- Spring 3 dependencies -->

<dependency>

<groupId>org.springframework</groupId>

<artifactId>spring-core</artifactId>

<version>${spring.version}</version>

</dependency>



<dependency>

<groupId>org.springframework</groupId>

<artifactId>spring-context</artifactId>

<version>${spring.version}</version>

</dependency>

  </dependencies>

_______________________________

3.Create Class for Spring instanciation Test : 
>slm.abdennour.springcore.Cv

package slm.abdennour.springcore;



import java.util.Random;



/**

 * 

 * @author  Abdennour عبد النور التومي

 * 

 * @see http://abdennour-insat.blogspot.com

 * @since 10 nov. 2012

 */

public class Cv {

    private String fullName; 

    public Cv() {

     this.fullName=getRandomString();

}

    public String getFullName() {

return fullName;

}



public void setFullName(String fullName) {

this.fullName = fullName;

}



public void display(){



     System.out.println(this.fullName);

    }



public String getRandomString(){

char[] chars = "abcdefghijklmnopqrstuvwxyz".toCharArray();

StringBuilder sb = new StringBuilder();

Random random = new Random();

for (int i = 0; i < 20; i++) {

char c = chars[random.nextInt(chars.length)];

sb.append(c);

}

String output = sb.toString();

return output;

}



}

4.Create Runnable Class & Main Method:

package slm.abdennour.springcore;



import org.springframework.context.ApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;



/**

 * 

 * @author Abdennour عبد النور التومي

 * 

 * @see http://abdennour-insat.blogspot.com

 * @since 11 nov. 2012

 */

public class CvRun implements Runnable {

ApplicationContext ctx;



public CvRun(ApplicationContext ctx) {

// TODO Auto-generated constructor stub

this.ctx = ctx;

}



public final void run() {

// TODO Auto-generated method stub

try {

Cv cvChild = ctx.getBean("cvThread", Cv.class);

System.out.println("Cv Thread Child =>" + cvChild.getFullName());

} finally {

// TODO: handle exception

}

}

public static void main(String[] args) {

ApplicationContext appCtx=new ClassPathXmlApplicationContext("ctx.xml");

Cv cvPatent = appCtx.getBean("cvThread", Cv.class);

System.out.println("Cv Thread Parent =>" + cvPatent.getFullName());

//Cv THread

CvRun cvrun=new CvRun(appCtx);

new Thread(cvrun).start();

//Cv Simple 

System.out.println("Simple");

for (int j = 0; j < 5; j++) {

System.out.print("cv Simple "+j+"=>");

((Cv)appCtx.getBean("cvSimple", Cv.class)).display();  

}



}



}

5.Add two beans in Spring Config XML : 
> one for singleton scope (which is the default scope)
>other for thread scope .

    <bean

        id="cvSimple"

        class="slm.abdennour.springcore.Cv"

         >

        

    </bean>

    <bean class="org.springframework.beans.factory.config.CustomScopeConfigurer" >



        <property name="scopes" >



            <map>



                <entry key="thread" >



                    <bean class="org.springframework.context.support.SimpleThreadScope" />

                </entry>

            </map>

        </property>

    </bean>



    <bean

        id="cvThread"

        class="slm.abdennour.springcore.Cv"

         scope="thread">

        

    </bean>

 
6.Run & Result :

 As the default scope is Singleton, cvSimple beans are the Same for all instanciation of Spring Factory container.  

7.Source Code :