tagged/marker interface in java

tagged/marker interface in java

View Answers

September 15, 2008 at 12:41 PM


Marker interface is interface which doesn't have any method but still holds information. Interfaces with no methods are called marker interfaces and they are used to tag classes. To understand how exactly this tagging is done, we need to talk about a seldom used instanceof java operator, which works in the following way: if(objectA instanceof ClassB) will yield true if objectA can be upcast to type ClassB.

This is simple code.

interface markerImp {

class MarkerTest implements markerImp{

public class TestInstanceOf {
public static void main(String []args){
MarkerTest mt = new MarkerTest();
if(mt instanceof markerImp){


Read for more information.




Related Tutorials/Questions & Answers:
tagged/marker interface in java - Java Beginners
tagged/marker interface in java  Hi! what is the exact meaning and usage of of tagged or marker interface. Exactly where we will use it in real time applications. thanks in advance. ashok  Hi, Marker
problem on marker interface - Java Beginners
tagged or marker interface is used to just identify the class, in real time...problem on marker interface  i want to know about marker interface... module,this tag or marker interface is useful. *. In serialization also
Java interface
Java interface  What is the List interface
Java Interface
Java Interface  Can an Interface have an inner class?  Yes, interface can have inner class. for example- public interface gyan { static...("in interface"); }; public static void main(String args
Java interface
Java interface  What must a class do to implement an interface?  It must provide all of the methods in the interface and identify the interface in its implements clause
Java interface
Java interface  What modifiers may be used with an interface declaration
Interface in java
Interface in java  An Interface method implemented in more than one different class with same method name. To avoid overriding of methods, we use ObjectReference for that class
java interface
java interface  Create a interface called student Define methods like get roll number Get name Get subject Create two classes Electronic student And history student Enter 5 students in the main class 2 of history and 3 elec
Marker Interface,Java Marker Interface
Interface in Java       In this section we will learn about Interface and Marker Interfaces in Java...;stopcar (int Obj); } Marker Interface In java
Interface - Java Beginners
Interface in Core Java  What is Interface? How Can i Use Interface in Core Java
Java cloneable interface
Java cloneable interface  What is cloneable interface
interface.  Write short note on interface.   Please visit the following link: Java Interface
Java interface reference
Java interface reference  When can an object reference be cast to an interface reference
interface - Java Beginners
interface  how to build interface in java programming language
Java Serializalble interface
Java Serializalble interface  What is the difference between Serializalble and Externalizable interface
Interface in Java
Interface in Java Interface in java programming languages is a collection... oriented concept. Through interface only abstraction is achieved in java. Syntax... is achieved in  Java. In an interface, only abstract method can be declared
Java Interface
Java Interface In this section we will discuss about the interface in Java... or more than one interfaces. Interface in Java is created for referencing something to other. To create an interface in Java the keyword "interface"
interface variables - Java Beginners
interface variables  why interface variable is by default final? what was the necessisity to make it final? plz explain me with good java prog
interface - Java Beginners
interface  what is an interface? when we will we use an interface in java? what will achived using interface?  Hi friend, Interface : An interface is a named collection of method definitions (without
INTERFACE  how interface support multiple inheritance in java
Java itrator interface
Java itrator interface  What is an Iterator interface?  An iterator over a collection. Iterator takes the place of Enumeration in the Java.... The iterator interface have these methods- boolean hasNext(); Object next
interface  what the use of interface?   An interface is one... variables.Any class can implement(inherit)the interface and make use of the methods(functions) and variables within it. In java, multiple inheritance
interface   what is the use of marking interface
interface  What is marker interface ?? what is its use in java programming?? is this us in programming ??Explain is implementation with code
Interface - Java Interview Questions
Interface  Respected sir why we use Interface in java? because we... the interface's example. But in java programming language interface is nothing... a new interface, you are defining a new reference data type. You can use
INTERFACE - Java Interview Questions
INTERFACE  Why Use Interface in Java?i want region ?plz post answer   Hi Friend, Interfaces form a contract between the class... the methods of the interface are implemented with the correct signature.Interfaces
Abstract class and interface in Java
Abstract class and interface in Java  What is the difference between abstract class and interfaces in Java?   Differences between an interface and an abstract class: At the same time multiple interfaces can
interface - Java Beginners
Interface meaning in java  What is the meaning of Interface? and why we need to call
Interface in Java
Interface in Java       In this section we will learn about Interface and Marker Interfaces in Java... Interface In java language programming, interfaces with no methods are known as marker
interface - Java Beginners
interface  I need the complete program for Design of java interface for Stack ADT and implement the same using array and linked list in java. Kindly send it as soon as possible. SOme of your solutions are not accessible
interface  why do we need interface in java..if it`s usefull for to obtain multiple inheritance in the sense how it gonna be achieved...and i can...)...the y we need interface...THis is question often i heard from my developer
for Interface in java? and want to know why they used interface instead of multiple inheritance? Thanks in advance   An interface is one which has abstract... method it will take.It creates complexity.Therefore java uses Interface
about interface - Java Beginners
of the given line Set si=new HashSet(); Problem is that Set is an interface and HashSet is a class... so how instantiation of interface is possible..or..what...://www.roseindia.net/java
interface  will the interface implements a interface   Hi Friend, No. Interface can extends another interface but cannot implements it, because interface will not contain the implementation. Thanks
Interface - Java Beginners
Interface  Dear Sir, Could you send me a java program for INTERFACE... java.lang.*; import java.io.*; import java.util.*; interface MyInterface { int...://www.roseindia.net/java/master-java/interface.shtml Thanks
interface - Java Beginners
Interface definition language example  example of interface definition  If it is a Class --> Interface is implemented. A class may implement multiple interfaces.if it is an Interface --> Interface can be extended
; Through interface, we can achieve the multiple inheritance. Java does...interface  What is the exact use of interface in real time scenario? some people says that interface provides multiple inheritance. Is it true
Interface in java with example
We are going to discuss about Interface in Java. Interface is blueprint... implement them. Java interface is nothing but is a empty collection... extending interface. Why use interface in java? We use itto achieve complete
interface - Java Magazine
engineering in gujrat.and i dont know about actual useof interface in java and in all java technology so plz solve my question sir  Hi Friend, Please visit the following link: http://www.roseindia.net/tutorial/java
interface variables - Java Beginners
interface variables  why interface variables are final? explain me with good program example?? i knw why the variable is static but,i dont knw why it is final by default? thanks in advance
Interface - Java Beginners
Interface  Assignment: You are given the following interface: interface Stats { double getAverage(); //returns the average of scores... } implement the interface in a class called Grades. The program will read a series
Graphic interface java help
Graphic interface java help  A modified checkers program with class name Checkers using double buffering. Somehow the program must have two top squares and two bottom squares. There should be two checkers of different color
JAVA INTERFACE - Java Interview Questions
JAVA INTERFACE  Can Any Interface will have inner classes... Whether an interface be final????  Hi friend, Yes, as for example, public interface TestInterface { // Inner class inside an interface
interface   Hi I have interface in that interface 3 methods are there , after some days client said that,i want to add one more method in that interface ,so how can add 4 method so that the implemented class did not affect
Gui Interface - Java Beginners
Gui Interface  hi I have two seperate interfaces in the same projects . my question is how can I access this interface using a jbutton (i.e jbutton = next where next points to another interface addCourse.java) What would
interface  can we extend interface?   Hi Friend, Yes an interface can be extended by other interface like using extends keyword interface A{ } interface B extends A{ } For Example: interface IntefaceA { void
Interface in JAVA - Java Interview Questions
. To sort out this flaw java has provided Interface which supports the Multiple... on the Interface. http://www.roseindia.net/java/java-exception/create-interface.shtml...Interface in JAVA  How interface fulfills all th facilities which
interface  develop a library interface which has drawbook(),returnbook()(with fine),checkstatus() and reservebook() methods.all the methods tagged with public
interface  develop a library interface which has drawbook(),returnbook()(with fine),checkstatus() and reservebook() methods.all the methods tagged with public
Java Graphical user interface
Java Graphical user interface  Hi, guys. I'm christina, need help... of your Java quiz GUI application are specified by the following program flow... of the screen when it starts. It provides an interface to register the student name