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Can we declare an interface in servlet
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In which class public static void main(String ar[]) is declard in java
sat.beit
- Jun 6th, 2008
Main method define in class from which excution of the application will get start.Which u can called main class of the file and file name will be the same as mainclass.
dvs198528
- Jun 6th, 2008
Public static void main(String ar[]) is in the class whose name is same as the name of the program name.Reason : To start the execution of the program initiating from main().
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What is garbage collection? can it be forced?
Karuna Reddy
- Jun 6th, 2008
Garbage Collection: If no longer any obejct need to any variable, java automatically reclaimes the memory.U can't force the GC, U have to give the request by using system.gc() and even not guarante that its immediatly to reclaims the memory...........
vinaymudgil007
- Jun 5th, 2008
garbage collection means releasing the memory free from the objects that can no longer be refferenced.No it can't be forced.............. although system.gc() or whatever may request for garbage collection but when exactly it would be started is at the discretion of JVM.
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If interface has got four methods,and I like to implement only two methods, how this could be achieved?
Karuna Reddy
- Jun 5th, 2008
Rest of the two method to open it and close the braces.EX:interface in1{ public void A(); &nb...
Karuna Reddy
- Jun 1st, 2008
public interface MyInterface1 { public void A(); public void B();public void C();public void D(); }package com.venkata.ust; public class MyClass1 implements MyInterface1 { @Override pu...
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In overriding, in super class we declared a method as protected & in sub class we declared that method as private. what happens?
vinaymudgil007
- Jun 4th, 2008
Well the answer to orignal question asked is -- compilation errorlogic --> In a subclass we can't make the method more restrictive than what is there in the super class.vinny
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I want to know the difference between these two programs mean the flow/*public class Aquestion { private int i = giveMeJ(); private int j = 10; private int giveMeJ() { return j; } public static void main(String args[]) { System.out.println((new Aquestion()).i); } } */public class Aquestion{private int j = 10;private int i = giveMeJ();private int giveMeJ(){ return j; }public static void main(String args[]){System.out.println((new Aquestion()).i);}}
ravikumar_kapala
- Jun 4th, 2008
Dear sabrik , we cannot call any method from the constructor . Please check your answer and correct it accordingly.
rahul singh
- Jul 25th, 2007
?In first program, ????? when j was initialize to i via method giveMeJ(),the value of j is 0. ????? therefor i is initialized by 0. in second program, ????? when j was initialized to i via giveMeJ(),v...
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I want to create two instances of a class ,But when trying for creating third instance it should not allow me to create . what i have to do for making this?
vinaymudgil007
- Jun 3rd, 2008
Here is a code snippet that will create maximum of two objects.*******************************************************************//This is a class that will create maximum of two objects for itself.c...
naveen.jayaram
- Sep 30th, 2005
by keepineg count of number of objectsfor examplepublic class ThreeObject{ private ThreeObject() { // no code req'd } public static ThreeObject getThreeObject() { int count;...
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I need some more information about interface. For Example there is no any functionality inside the method which is declared in any interface. Then why i want to implement that interface to my class. 2. Statement is an interface. When i say stmt.executeQuery(). I am getting the records in my ResultSet. How it is possible?.. since there is no functionality insid the methods which is declared in Statement Interface. What is happning here?
An idea
vinaymudgil007
- Jun 3rd, 2008
Well the answer given by sarat is a very good one & explains the concept.....
sasi
- Jul 20th, 2006
hi.....for example..take SUN as example..they provides..only interfaces..that means..they give only NULL implementations..i.e.what is the returntype of the interface..what is the method & it...
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Do primitive types have a class representation
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In Execption handling What is exactly difference between throws and throw?
Karuna Reddy
- Jun 1st, 2008
Throw: We can use our own exceptions ie User Defined Exceptions.Throws: we can raise the exceptions more than one at a time
vinaymudgil007
- May 29th, 2008
Throw -- used to throw an exception explicitlyThorws -- indiacates the calling method that the called method my throw specified exceptionVinny
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How and when to prevent inheritance?
vinaymudgil007
- May 29th, 2008
Two ways: -(1) mark the class as final(2) make its constructor private -- in this case we will also not be able to instantiate a class from any other classany doubts, let me knowVinny
iyck
- Jul 5th, 2006
If we make Final class we cannot extend, also if we make all the constructor private then we cannot extend that class, is this also prevents inheritence?
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Where Scanner Class used in JAVA?
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Servlets are multi threaded by default. If there are concurrent requests to the same servlet the servlet container generates another instance of the servlet . Is this the reason y servelts are multi threaded by default?? Is there any way the multi threaded feature can be achieved ?
vinaymudgil007
- May 21st, 2008
one thing surely i can say and that is "only one insatnce of the servelet would be created" and multiple threads would be used to serve the request.......well if the requests are very large ...
AjayMukiri
- Apr 30th, 2008
Servlets are multi threaded by default. If there are concurrent requests to the same servlet the servlet container generates New Thread . So this the reason servelts are multi threaded by default.
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What are the other ways to prevent a class from being subclassed.one way is to declare the class final.does declaring a class private prevent it from being subclassed?
vinaymudgil007
- May 21st, 2008
Pankaj Vishwani.....your code is compiling because you have prefixed the kerword void before the constructor of stud class...... hence its not a constructor anymore.... its beheaving like a method as ...
Ram
- Jan 8th, 2007
Well pankaj. The deal is to make the constructor private. In your example you have created a method as private as constructor do not have any return type. So try compiling again. cheers. Ram
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Which is superclass of Exception?many people think that object,no there is particular class which is superclass of all exception it starts with letter B,plz tell me
nv_krishna
- May 19th, 2008
The super class of all Exceptions in java is Throwable. It has two sub-classes :: Exception and ErrorException forms the base class for Exceptions like ArrayIndexOutofBounds etc..Error is another sub-class, these are catastrophic in nature and not caught by normal java program..
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The result wil be 5..!! and not 6 why???">Solve it... public class test {public static void main(String[] args) { int i=5; i=i++; System.out.println("result::"+i); }}The result wil be 5..!! and not 6 why???
tarazan2jungle
- May 7th, 2008
Dear Friend, this is post increment, that is first assign the value and then increment.so in this case you first assign the value, so i become 5, now you increment which is of no use.that's why the answer is 5;But rather assigning a value if you directly write i++, then the value become 6;
for4me
- May 4th, 2008
It is same as System.out.println(i++);public class test{public static void main(String[] args) ??? {??? ??? int i=5; ??? ??? System.out.println("result::"+i++); ??? }}It prints 5? first then increments.
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How the Multiple Inheritance is problematic. In other words why this feature from C++ is not taken into Java?
bewithmd
- May 7th, 2008
Consider you are having 2 base classes each with 4 methods( might have same method, doesn't matter). Now you are going to create class 3 by inheriting the properties of both the base classes ( 1 and 2...
sampra
- Feb 14th, 2008
When Class C is sub class of both A and B and if A and B consists similar properties and methods so it will consume more memory and baseic concept of doveloping java is to save the memory so taht they create java for such small deviceslik moblie ipot etc
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Java.awt.Color class
the Color class contains some color names as constant variables . but it is twice. what for it.it have two variables like RED and red. what for it. i know that one is for set and get Color.but how the other is used. is it using for ignoring case ?
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What is JIT? Is it bundled with JDK? If so what is the role of interpreter(java)? plz explain in detail.
phanikhk
- Apr 9th, 2008
In a bytecode-compiled system, source code is translated to an intermediate representation known as bytecode. Bytecode is not the machine code for any particular computer, and may be portable among co...
sampra
- Feb 22nd, 2008
JIT is just-in-time. Yes JIT is bundled with JDK. Compiler converts .java file into .class file then interpreter reads bytecodes and that's why JIT.its similar to interpreator but it is faster thn interpreator
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How we can create marker interface in java?
trinadh
- Mar 19th, 2008
We can create it by having no method defenitions on out own interface .u first extend Serializable interface to ur Apple interface and after that what ever class implements ur Apple interface will be Serializable OK
sampra
- Mar 11th, 2008
To inform to JVM that the objectedt created for particular class will be follw this property
Core Java Interview Questions
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