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What modifiers may be used with an inner class that is a member of an outer class
A (non-local) inner class may be declared as public, protected, private, static, final, orabstract.
priyam
- Oct 14th, 2022
It can have any access modifiers public ,private,protected,default like any ordinary top level class.
jigyasa_sienna
- Jun 7th, 2009
Public can be used as it is the only access modifier which can access?any class or methods from any class or package.
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Is a class a subclass of itself
A class is a subclass of itself.
AGRAWALNIDHI
- May 2nd, 2009
No, a class can't be a subclass of itself. class A extends AThis is cyclic inheritance which is not possible.
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What is the unit for 1000 in the below statement?ob.sleep(1000)
A) Int millisecondsB) Double millisecondsC) long millisecondsD) Float milliseconds
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State true or false :- The word synchronized can be used with only a method.
A) FalseB) True
raghuprasad
- Aug 25th, 2008
False. The word synchronized can also be used to make a block of code synchronized.Eg: synchronized(object) { ............code........... }Raghu.
jagadeesh_32
- Aug 23rd, 2008
False, because synchronized keyword is used as block also.Ex:synchronized blocks can lock within code for just a few instructions and on any object whatsoever: synchronized (anyObject) { // .. object is handled atomically here }
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Which of the following are true about the Error and Exception classes?
A) Both classes extend Throwable.B) The Error class is final and the Exception class is not.C) The Exception class is final and the Error is not.D) Both classes implement Throwable.
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The term _____________ refers to a class's direct ancestor or to any of its ascendant classes.
Skill/Topic: InheritanceA) Sub ClassB) Super ClassC) Class hierarchy
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Java I/O is based on the concept of _________
Skill/Topic: AWT & AppletsA) ClassesB) StreamsC) BuffersD) Threads
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The concept of polymorphism is often expressed by the phrase
Skill/Topic: AWT & AppletsA) One interface, multiple methodsB) Multiple interface, one MethodC) Multiple interface, Multiple methodD) One interface, One method
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_________ is used to destroy the objects created by the constructor methods.
Skill/Topic: AWT & AppletsA) finalize()
amitkaushik8
- Jul 26th, 2011
Finalize method is called by the garbage collector to free up the system memory
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What is difference between string and stringBuffer with example
sankarsansinha
- Feb 5th, 2009
String is immutable
String buffer is mutable
Ex String str = "abc";
str = "new String";
this will create new memory location and stores "new String"
but in String buffer
StringBuffer strBuf = "abc";
strBuf = "new String"
it will overwrite in same memory locationsandesh.giri
- Jun 15th, 2008
Java provides the StringBuffer and String classes, and the String class is used to manipulate character strings that cannot be changed. Simply stated, objects of type String are read only and immutabl...
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The real time environment , when do we go for abstract class and when do we go for interfaces , can any one please revert back in this regard?
sadashivarao
- Jun 18th, 2006
we use the abstract class when we want to specify common featurs of a group of objects, when we dont how to implement them.we use interfaces, when we know the features, but we dont know how...
sadashivarao
- Jun 18th, 2006
we use abstract class when we want specify common features of a group of objects, when we dont know how to implement them.we use interfaces when we know features of a group of objects, but we dont kno...
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Parent p = new Parent(); // Can we access x using the p reference?
System.out.println("X in parent is " + p.x); // Compiler error!
}
}
when i compile this code it dosen't give any error.even though both classes are in diffrent package.
but in pdf it mentioned that it gives an error because you are trying to access the protected variable
using the instance of the super class
if the above code is write then what is logic behind the protected member of super class and if sub class
in different package try to access the member of the super class.">Hi,I am preparing for sjcp exam.my quetion is about the protected class. it have one super and sub class example ,below example i read from one pdf.package certification;public class Parent { protected int x = 9; // protected access}----------------------------package other;import certification.Parent;class Child extends Parent {public void testIt() { System.out.println("x is " + x); // No problem; Child inherits x Parent p = new Parent(); // Can we access x using the p reference? System.out.println("X in parent is " + p.x); // Compiler error!}}when i compile this code it dosen't give any error.even though both classes are in diffrent package. but in pdf it mentioned that it gives an error because you are trying to access the protected variableusing the instance of the super class if the above code is write then what is logic behind the protected member of super class and if sub classin different package try to access the member of the super class.
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Int [ ] [ ] scores = { { 1, 2, 3} , { 2, 4, 6}, { 3, 6, 9} };how many objects in heap after the above stmt ?
satabdi_d
- Jan 15th, 2008
The preceding code creates a total of four objects on the heap. First, an arrayof int arrays is constructed (the object that will be assigned to the scoresreference variable). The scores array has a l...
venkatgonu12
- Aug 24th, 2007
two dimensional array object. but only one object will be created when you created new object created that memory stored only one object
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How do u ping in java
jan.cajthaml
- Apr 14th, 2012
Its quite simple. You need to do this two steps. First send Packet with seq=0 ack=0 flag=1 and data 1 Then wait until the server confirms you this packet, that mean wait until you receive the packet...
me
- Feb 5th, 2007
Ping is based on ICMP. Java has no support for this. They have UDP and TCP sockets. In Java 5 there is an isAlive call that says if a host is alive or not, but is not a ping. You could do the same...
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If we declare main method as private instead of public, Will it execute or not.
kiran
- Aug 16th, 2007
There is no exceptionIn Java the compiler compiles the programe but whenever we execute that we wont get any output because of?access specifier PRIVATE. The main method?does not?not call the member function (methods)
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What is synchronization and why is it important
With respect to multithreading, synchronization is the capability to control the access ofmultiple threads to shared resources. Without synchronization, it is possible for onethread to modify a shared object while another thread is in the process of using orupdating that object's value. This often leads to significant errors.
bijuleo
- Nov 8th, 2007
Synchronization is the mechanism that ensures that only one thread is accessed the resources at a time. In a practical point of view assume that two threads are trying to update bank balance at the sa...
priya
- Sep 13th, 2007
Synchronisation is a phenomenon in multithreaded programming which enforce synchronicity when we need it. For eg, if we want two threads to share a complicated datastructure?we need to ensure that th...
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What are wrapped classes
Wrapped classes are classes that allow primitive types to be accessed as objects.
Djava
- Aug 10th, 2009
Wrapper Classes are like a wrapper over a resource that is If I have to access a resource I can access it throught that wrapper.For example:'java.lang.Integer' is a wrapper class. with r...
tech.abha
- Feb 3rd, 2009
Wrapper classes are classes that are used to make primitive variables into objects, and to make wrapped objects into primitives. int, boolean, double are all primitive data types and their respective ...
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