Top Core Java Interview Questions :: Top Core Java Interview Questions en-us explain oops concepts with examples? There are three types of oops in java. 1.Encapsulation:Encapsulation is mechanism,that binds together data and code its manipulates. Ex:suppose we are writing one bean.we declaring two private variables.we are providing setters and getters method What is the difference between C++ & Java? C++ is the advanced version of c i.e.C with Classes whereas Java is the platform independent as it works on any type of operating systems. what are the oops concept in java explain with real time examples Encapsulation Abstraction polymorphisms inheritance/delegation explain System.out.println System: System refers to current java program. out: out refers to output device. by default it is monitor. println: to print the specific string onto output device in next line what is difference Between Core Java and advance java See the diffrence is that core java is the fundamental for java that will be used in any java technology without this no one can jump on any advance java technology. Where as advance java is specialisation in some domain , as someone in networki Difference between array and arraylist. A java.util.ArrayList has the following characteristics over an array: 1. Provides a resizable array implementation 2. Implements the java.util.List interface 3. Has a tuning parameter called initialCapacity which specifies the number of eleme Difference between JDK, JRE, JVM JDK or the Java Development Kit is a set of a Java compiler, a Java interpreter, developer tools, Java API libraries, documentation which can be used by Java developers to develop Java-based applications. JRE or the Java Runtime Environment is what is the Diff. between Access Specifiers and Access Modifiers? Access specifiers :: The access specifier determines how accessible the field is to code in other classes. Access ranges from totally accessible to totally inaccessible. You can optionally declare a field with an access specifier keyword: p What is static variable and static method? static variables are classes variables not instance variables .They are instantianted only once for a class.They are initialised at class load time. Static method can be referenced with the name of the name of the particular object of that cla why java does not support multiple inheritance Java absolutly support multiple inheritence in terms of Interface.We can extend one class only to avoid ambiguity problem.In interface we have to define the functions.So we don't get any ambiguity.In c++ it is big problem with multiple i what is difference between throw and throws in exception? "throw" is used to handle user-defined exception. JVM handles the exceptions which are specified by "throws" what is difference between class and object? Class is a template(type) or blue print its state how objects should be and behave. eg consider a construction plan which is a class with this description mentioned in a plan we can constructs 'n' number of buildings of same type. th what is the difference between abstract class and Interface?where we 1)We define an Interface in the Java application with a set of abstract methods without any implementation. Which means all the methods of an interface are by default abstract methods and public methods. 2)Once an Interface is defined in the What is singleton class? Singleton class: This is a class which can be instatiated only once. Eg: Public class Singleton { private static single = new Singleton(); Private Singleton(); {} } For a singleton class, the constructor is made private and In Java why we write public static void main(String args[]) why not m static because once the class is loaded the main() will be invoked first. void because main()is not returning any value.