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Can consturctors have below modifiersa) finalb) voidc) static
sekhar511
- Dec 10th, 2010
Constructors cannot have return types and modifiers where final, void, static are not allowed as modifiers to constructors.
pramod.cbit
- Mar 22nd, 2008
no..construtors are meant for creating objects and it is not a method but loojk likes method. 1.so u cant put final to other than method,vaRIABLE ,class. 2.if u put satitic means u r breaking ...
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String b=new String("A");
String c="A";
String d="A";
Then which of the following returns true?
1. if(a==b)
2. if(b==c)
3. if(c==d)
4. if(d==a)">String a=new String("A");String b=new String("A");String c="A";String d="A";Then which of the following returns true?1. if(a==b)2. if(b==c)3. if(c==d)4. if(d==a)
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What is the size of Interger wrapper class?
ramesh chandra
- Jan 2nd, 2007
hi size of integer wrapper class will be find out using size of opreator by passing the object or instance of the class as a parameter
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When we have to use FileInputStream() or FileReader()?
Thiyagarajan.N
- Mar 20th, 2007
FileInputStream is used to read the file byte by bytes. FileReader is used to read the file character by character.
sivanesh.a
- Dec 24th, 2006
FileInputStream: reading data as stream.FileReader: reading data as binary
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Does Java have pass by value or pass by reference or both?Please Explain it with example.
Casttro
- Mar 15th, 2007
Java is defined in both "pass by value" and "pass by ref" . In pass by value technique is just a copy of aurguments are passed to the method ( EX: cal(20,5.225) and in pass by ref technique is just a ref to the values are passed to the method (EX:cal(Cat, Dog))
ajaykjha
- Oct 15th, 2006
Java has both pass by value and pass by ref. When primitive types are passed, they are passed by value but when objects are passed, they are passed by ref. And reference itself is passed by value.
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What is full form of 'J2SDK' in Java
Feroz Majid Shah
- Oct 7th, 2006
Java Standard Development Kit
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We know that when execution of java starts, 1 st public static void main(String args[]) methodis execute. so i have ask you that ,when main method is executed, it s static method. so at the time of execution of main method, object is not their. after that code under main method is run which contain object of classes.so Q. when main method is executed,at that time object is not in memory so at that time can i say that JAVA IS NOT OBJECT-ORIENTED???
ACCORDING TO ME yes,after main methode,code run which will create object after main method, java is OBJECT ORIENTED.
byteTech
- Jan 9th, 2007
Main() method is the place from where the the JVM starts executing the code within a particular class, there has got to be some point and in this case its the main() method. It does not make Java one wee bit obj oriented
sivanesh.a
- Dec 4th, 2006
Main function is static. so no object required....since main() is inside a class it is purely object oriented.
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When object is created in Java. Is it during compile time or run time?
Keshav v. devale
- Sep 1st, 2014
Array of object created on run time?
Because user assigned values by runtime
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Primitive Types
What happens when you add a primitive type (e.g. double) value to a collection?
pdureja
- Apr 6th, 2011
Collection can hold Objects but not primitives. Prior to Java5, we need to wrap primitive using wrapper classes and in java 5 autoboxing do it automatically.Prior to java 5:xyzCollection.add(new Integer(10))In javaxyzCollection.add(10) //will do autoboxing
mani.sivapuram
- Mar 11th, 2011
Every one says that every concept in Java is purely prepared in Object Oriented Form only in you need to remember one thing when Java people preparing the Java they try to create an alter native t...
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How are Observer and Observable used
Objects that subclass the Observable class maintain a list of observers. When anObservable object is updated it invokes the update() method of each of its observers tonotify the observers that it has changed state. The Observer interface is implemented byobjects that observe Observable objects.
jimmy514in
- Jul 4th, 2010
An observable object can have one or more observers. An observer may be any object that implements interface Observer. After an observable instance changes, an application calling theObservable's noti...
jimmy514in
- Jul 4th, 2010
observer pattern (a subset of the publish/subscribe pattern) is a software design pattern in which an object, called the subject, maintains a list of its dependants, called observers, and notifies the...
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Does garbage collection guarantee that a program will not run out of memory
Garbage collection does not guarantee that a program will not run out of memory. It ispossible for programs to use up memory resources faster than they are garbage collected.It is also possible for programs to create objects that are not subject to garbage collection
TestMeUser
- Jun 18th, 2009
Static objects will never be garbage collected. So try using them if you are desperate to write code that way.
dgiscool
- Oct 9th, 2005
The object is eligible for garbage collection only if there is no strong reference to the object. An exception to this is island of references(where all objects point to each other).And you should ne...
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If a variable is declared as private, where may the variable be accessed
A private variable may only be accessed within the class in which it is declared.
Mithun Challa
- Jan 6th, 2008
It may be accessed in any of the methods defined in that class. Generally for the security of the variables we declare them as private and using the public methods in the class we use them. Makinng sure that variables are accessible only in that class
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How does multithreading take place on a computer with a single CPU
The operating system's task scheduler allocates execution time to multiple tasks. Byquickly switching between executing tasks, it creates the impression that tasks executesequentially.
aseemak
- Dec 22nd, 2007
Hyperthreading processors have more than one execution units but only one processor core, thats how multiple tasks are performed simultaneously
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Which package is always imported by default
The java.lang package is always imported by default.
peter
- Jan 18th, 2016
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What is the purpose of garbage collection
The purpose of garbage collection is to identify and discard objects that are no longerneeded by a program so that their resources may be reclaimed and reused.
sivapurammani
- Dec 17th, 2013
In simple terms we can say garbage collector removes the unreferenced objects from the memory. In general the memory should have some limitation. In JVM for accomplishing tasks we create objects and ...
pardeep131085
- Aug 21st, 2013
garbage collection is the process of looking at heap memory, identifying which objects are in use and which are not, and deleting the unused objects. An in use object, or a referenced object, means th...
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What modifiers may be used with a top-level class
A top-level class may be public, abstract, or final.
mrkab
- Nov 15th, 2007
The modifiers a top-level class can have are public and either abstract or final. A nested class is any class whose declaration occurs within the body of another class or interface. A top level class ...
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Can we add Hashtable/HashMap to a vector
funnyjoy_12
- Sep 6th, 2007
import java.util.*;class HashtableinVector { public static void main(String args[]) throws Exception { Vector v=new Vector(); Hashtable h1=new Hashtable();&n...
penchalaiah
- May 4th, 2007
Write a small code and show how it is possible
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What is the diffrence between an Abstract class and Interface
Sujit4175
- Jun 23rd, 2011
As far as difference is concerned, then the only difference between interface and Abstract class is:?In the interface we can only declare a method, we can not define it within interfaceBut in the abs...
Vijay Chaudhary
- Jul 31st, 2005
Variables declared in Interface are static and final by default.
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