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 Spring > Core > Application Context Aware

Application Context Aware 

Spring Inversion of Control (IoC) also known as Dependency Injection (DI) is a process by which objects define their dependencies with collaborating objects. Spring provides ApplicationContextAware interface which allows us to have access to the ApplicationContext that created the bean implementing this interface. 

ApplicationContextAware.java  
package org.springframework.context;
import org.springframework.beans.BeansException;

public abstract interface ApplicationContextAware
{
  public abstract void setApplicationContext(ApplicationContext paramApplicationContext)
    throws BeansException;
}
File Name  :  
/SpringCore001/conf/aware/app_context.xml 

File Name  :  
com/bethecoder/tutorials/spring3/basic/SimpleBeanFactory.java 
   
package com.bethecoder.tutorials.spring3.basic;

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;

public class SimpleBeanFactory implements ApplicationContextAware {

  private ApplicationContext applicationContext = null;
  private int count = 0;
  
  @Override
  public void setApplicationContext(ApplicationContext applicationContext)
      throws BeansException {
    System.out.println("Injecting ApplicationContext");
    this.applicationContext = applicationContext;
  }

  public SimpleBean getSimpleBean() {
    SimpleBean simpleBean = (SimpleBean) applicationContext.getBean("template");
    simpleBean.setSimpleProp("ABC" + ++count);
    return simpleBean;
  }
}
   

File Name  :  
com/bethecoder/tutorials/spring3/basic/SimpleBean.java 
   
package com.bethecoder.tutorials.spring3.basic;

public class SimpleBean {

  private String simpleProp;

  public String getSimpleProp() {
    return simpleProp;
  }

  public void setSimpleProp(String simpleProp) {
    this.simpleProp = simpleProp;
  }
  
}
   

File Name  :  
com/bethecoder/tutorials/spring3/tests/aware/ApplicationContextAwareTest.java 
Author  :  Sudhakar KV
Email  :  [email protected]
   
package com.bethecoder.tutorials.spring3.tests.aware;

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

import com.bethecoder.tutorials.spring3.basic.SimpleBean;
import com.bethecoder.tutorials.spring3.basic.SimpleBeanFactory;

public class ApplicationContextAwareTest {

  /**
   * @param args
   */
  public static void main(String[] args) {

    System.out.println("Initializing ApplicationContext");
    ApplicationContext factory = new ClassPathXmlApplicationContext("app_context.xml");
    System.out.println("ApplicationContext Initialized");
    
    SimpleBeanFactory simpleFactory = (SimpleBeanFactory) factory.getBean("simpleFactory");
    
    SimpleBean simple = simpleFactory.getSimpleBean();
    System.out.println(simple + "->" + simple.getSimpleProp());
    
    simple = simpleFactory.getSimpleBean();
    System.out.println(simple + "->" + simple.getSimpleProp());
    
    simple = simpleFactory.getSimpleBean();
    System.out.println(simple + "->" + simple.getSimpleProp());
  }

}
   

It gives the following output, 
Initializing ApplicationContext
Injecting ApplicationContext
ApplicationContext Initialized

com.bethecoder.tutorials.spring3.basic.SimpleBean@97d01f->ABC1
com.bethecoder.tutorials.spring3.basic.SimpleBean@e0a386->ABC2
com.bethecoder.tutorials.spring3.basic.SimpleBean@feb48->ABC3



 
  


  
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