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How can we create object of any class without using new keyword?
Devapangu Mangaiah
- Mar 19th, 2012
Using factory method
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What is the Vector class
The Vector class provides the capability to implement a growable array of objects
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Which class is extended by all other classes
The Object class is extended by all other classes.
Sandhya.Kishan
- Mar 24th, 2012
The object class is the super class of every class and it is extended by all the other classes.
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What is the difference between the Font and FontMetrics classes
The FontMetrics class is used to define implementation-specific properties, such asascent and descent, of a Font object.
Sandhya.Kishan
- Mar 24th, 2012
Font class is used to set or retrieve the screen fonts.The Font class maps the characters of the language to their respective glyphs. The FontMetrics class defines a font metrics object, which encapsu...
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What is the SimpleTimeZone class
The SimpleTimeZone class provides support for a Gregorian calendar.
Sandhya.Kishan
- Mar 24th, 2012
Time zone that is use with a Gregorian calendar is a subclass of TimeZone which represented by SampleTimeZone class.By using the base time zone offset from GMT time zone ID and rules, for starting and ending the time of daylight we create SampleTimeZone class.
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What is the purpose of the File class
The File class is used to create objects that provide access to the files and directories of alocal file system.
Sandhya.Kishan
- Mar 24th, 2012
File class is used to provide methods to perform some basic file-system operations such as checking the file length,
create/remove folders etc.File class is used to read and write data to and from files.It provides access to directories of local file system with the help of objects created. -
Which Math method is used to calculate the absolute value of a number
The abs() method is used to calculate absolute values.
Sandhya.Kishan
- Mar 24th, 2012
To returns the absolute value of a specified number we use the method abs(x).
Example:
int value1 = -1000;
int abs1 = Math.Abs(value1);
output will be 1000 which is an absolute value.
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What are the advantages of developing an n-tiered system
Sandhya.Kishan
- Mar 24th, 2012
Some advantages 1.N-Tier systems are useful as they allow a business to utilize any combination of software and hardware resources that they want or need it also allows to add on any components that...
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Sizeofthe Variable
How to find the size of the (datatype) variable in java?in c we use sizeof() operator for for finding size of data type
Sandhya.Kishan
- Mar 27th, 2012
There is no any particular function in java to find the size of the variable,because java removes the need for an application to know about how much of space needs to be reserved for a primitive value, an object or an array with a given number of elements.
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What is the GregorianCalendar class
The GregorianCalendar provides support for traditional Western calendars.
Sandhya.Kishan
- Mar 27th, 2012
GregorianCalendar is a concrete implementation of a Calendar for Gregorian calendar.Traditional Western calendars are supported by the GregorianCalender.It has two standard eras BC and AD.Only the current era recognizes the implementation of this calender class.
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What is an abstract method
An abstract method is a method whose implementation is deferred to a subclass.
Sandhya.Kishan
- Mar 27th, 2012
Method which is define in the class without implementation is call as Abstract Method. Abstract Method must be define with abstract keywords.
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What are the high-level thread states
The high-level thread states are ready, running, waiting, and dead.
Sandhya.Kishan
- Mar 27th, 2012
The thread states are 1.Ready state-This state signifies that the thread is ready for execution. 2.Running state-A thread in running state has access to the CPU i.e.,the thread is being executed. 3.Wa...
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What is the purpose of the System class
The purpose of the System class is to provide access to system resources.
Sandhya.Kishan
- Mar 27th, 2012
The purpose is that it provide access to externally defined properties and environment variables.It is used to read the system properties.
By using this class we can read time, and date, current running process,current Runtime.
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Can an exception be rethrown
Yes, an exception can be rethrown.
Sandhya.Kishan
- Mar 27th, 2012
Exceptions can be re-thrown.Rethrowing the exception is useful if we want to log the same exception, but not to handle it.
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How are the elements of a CardLayout organized
The elements of a CardLayout are stacked, one on top of the other, like a deck of cards.
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What is the relationship between clipping and repainting
When a window is repainted by the AWT painting thread, it sets the clipping regions tothe area of the window that requires repainting.
Sandhya.Kishan
- Mar 29th, 2012
Confining the paint operation to a particular ares or shape is done be a process called ad clipping.
On the request of repainting the clipped areas are set to repaint windows. -
What is the highest-level event class of the event-delegation model
The java.util.EventObject class is the highest-level class in the event-delegation classhierarchy.
Sandhya.Kishan
- Mar 29th, 2012
The highest level classof event delegation model is java.util.EventObject class because it contains all classes and interfaces that support all kinds of event handlings.
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What state is a thread in when it is executing
An executing thread is in the running state.
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Which class is the immediate superclass of the Container class
Component
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What is the difference between a public and a non-public class
A public class may be accessed outside of its package. A non-public class may not beaccessed outside of its package.
Sandhya.Kishan
- Mar 31st, 2012
A public class will have access specifier "public" and its members can be accessed with in and out of the class in which they are specified. A class which doesnt have the public access specifier are c...
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