Category Archives: OCJP Unit 2

Polymorphism in Java

By | March 30, 2014

This article contains… What is Polymorphism ? Reference variable types and Object Example of Polymorphism Runtime and Compiletime Polymorphism Example of both SCJP exam objective 5.2

Inheritance, IS-A and Has-A

By | February 28, 2014

Contents : IS-A relationship in OOP (Inheritance) Has-A relationship (Association) Different type of Association : Aggregation and Composition Example of each type SCJP exam objective 5.5

Unit 2 (Prog 6) : Inheritance in JAVA

By | February 10, 2014

Content : What is Inheritance ? Example of Inheritance. Reason to use Inheritance. What you can do in child class ?

Unit 2 (Prog 8) : Encapsulation in JAVA

By | February 1, 2014

Content  : What is Encapsulation ? Difference between Information hiding and Encapsulation. How to implement : Example of Encapsulation Why we need Encapsulation ?

Unit 2 (prog 7) : Test clone() method

By | June 19, 2013

In this Example, you can find the Cloneable interface and Clone method usage in java. and also various ways to create object in java. /*  * Object cloning is a way to create exact copy of an object.  * To use clone() method of java.lang.Cloneable interface, class must implement it else CloneNotSupportException will be thrown.… Read More »

Unit 2 (Prog 6) : Test Static Keyword

By | June 9, 2013

This article covers basics of static keyword, static methods and static variables. /*  * STATIC METHODS :  * 1. Static method can not access non-static (Instance) variable or method.  * 2. Static method can not be overridden they are redefined.  */

Unit 2 (Prog 5) : Constructors in java

By | June 5, 2013

Constructor Demo code… /*  * 1. Constructor can use any return type.  * 2. Constructor name must match the name of class.  * 3. constructor must not have a return type.  * 4. If you see a method with return type having same name as class than it is just a method.  * 5. if… Read More »

Unit 2 (Prog 4) : Test Overloading and Overriding

By | June 3, 2013

Overloading v/s Overriding methods… class Operator {           public int operation(int x, int y) {                     System.out.println(“First method invoked from parent class.”);                     return x + y;           }… Read More »

Unit 2 (Prog 3) : Test equals() method.

By | June 2, 2013

Testing of equals() method and overriding equals() method of Object class. // Overriding equals() method will make an object identical // to use a object as a key, one has to override equals() method of Object class   public class EqualsTest {           public static void main(String[] args) {    … Read More »

Unit 2 (Prog 2) : Accessing Super Class method

By | June 2, 2013

Accessing Super Class method : class ParentShape {           public void displayShape(Object o) {                     System.out.println(“displaying parent shape from ” + o.toString() );           } // more code } class ChildOne extends ParentShape {        … Read More »