12-Using-ApplicationContextAware

As of now we have ApplicationContext in main class because nowhere else require to use getBean configuration. There are some scenarios where we require ApplicationContext in dependent classes and we can access ApplicationContext by implementing ApplicationContextAware interface.

ApplicationContextAware interface provide to know context information like context aware (Know where you live).

BeanNameAware interface provide to know bean information like name aware (know who you are).

DrawingApp.java

package org.yash.watertechsol;

import org.springframework.context.ApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;

public class DrawingApp {

                public static void main(String[] args){

                                ApplicationContext context = new ClassPathXmlApplicationContext("spring.xml");

                                Triangle triangle = (Triangle)context.getBean("triangle");

                                triangle.draw();

                }

}

Triangle.java

package org.yash.watertechsol;

import org.springframework.beans.BeansException;

import org.springframework.beans.factory.BeanNameAware;

import org.springframework.context.ApplicationContext;

import org.springframework.context.ApplicationContextAware;

public class Triangle implements ApplicationContextAware, BeanNameAware {

     

      private Point pointA;

      private Point pointB;

      private Point pointC;

      private ApplicationContext context = null;

     

      public Point getPointA() {

            return pointA;

      }

      public void setPointA(Point pointA) {

            this.pointA = pointA;

      }

      public Point getPointB() {

            return pointB;

      }

      public void setPointB(Point pointB) {

            this.pointB = pointB;

      }

      public Point getPointC() {

            return pointC;

      }

      public void setPointC(Point pointC) {

            this.pointC = pointC;

      }

      public void draw(){

            System.out.println("Point A = (" + getPointA().getX()+", "+getPointA().getY()+")");

            System.out.println("Point B = (" + getPointB().getX()+", "+getPointB().getY()+")");

            System.out.println("Point C = (" + getPointC().getX()+", "+getPointC().getY()+")");

      }

      @Override

      public void setApplicationContext(ApplicationContext context)

                  throws BeansException {

            this.context = context;

            Triangle t = (Triangle)context.getBean("triangle");

            t.draw();

      }

      @Override

      public void setBeanName(String beanName) {

            System.out.println("BeanName: "+beanName);

      }

}

Point.java

package org.yash.watertechsol;

public class Point {

      private int x;

      private int y;

     

      public int getX() {

            return x;

      }

      public void setX(int x) {

            this.x = x;

      }

      public int getY() {

            return y;

      }

      public void setY(int y) {

            this.y = y;

      }

}