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How are commas used in the initialization and iteration parts of a for statement
Commas are used to separate multiple statements within the initialization and iterationparts of a forstatement.
Sandhya.Kishan
- Jul 24th, 2012
The multiple statements with in the initialization and in the iteration parts are separated using commas.
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What is an abstract method
An abstract method is a method whose implementation is deferred to a subclass.
Sandhya.Kishan
- Apr 18th, 2012
A method which has method declaration and definition but no method body is known as an abstract method i.e it is a method without any implementation(without braces, and followed by a semicolon),
abstract void add(int X, int Y);
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What is the relationship between the Canvas class and the Graphics class
A Canvas object provides access to a Graphics object via its paint() method.
Sandhya.Kishan
- Apr 23rd, 2012
The graphics class object can be accessed by the paint() method which is provided by the canvas class object.
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What are the high-level thread states
The high-level thread states are ready, running, waiting, and dead.
Sandhya.Kishan
- Apr 18th, 2012
The high level states of a thread are ready state,running state,waiting state and dead state.
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What value does read() return when it has reached the end of a file
The read() method returns -1 when it has reached the end of a file.
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What is the difference between a static and a non-static inner class
A non-static inner class may have object instances that are associated with instances ofthe class's outerclass. A static inner class does not have any object instances.
Sandhya.Kishan
- Jul 25th, 2012
A static inner class need to be referred by the class name being it is static. A static inner class can have access even to the private members of the outer class. The non-static inner class has the ...
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What is the Dictionary class
The Dictionary class provides the capability to store key-value pairs.
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How are the elements of a BorderLayout organized
The elements of a BorderLayout are organized at the borders (North, South, East, andWest) and the centerof a container.
Sandhya.Kishan
- Jun 2nd, 2012
The elements of a borderlayout are organized in the center and at the borders of the container.
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What is the % operator
It is referred to as the modulo or remainder operator. It returns the remainder of dividingthe first operandby the second operand.
Sandhya.Kishan
- Apr 23rd, 2012
It is a reminder operator.
if r = x % y, then a non-negative q exist, such that
x = q*y + r.
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When can an object reference be cast to an interface reference
An object reference be cast to an interface reference when the object implements thereferenced interface.
Sandhya.Kishan
- Jul 25th, 2012
When an object implements the referenced interface then the object reference be cast to an interface reference.
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What is the difference between a Window and a Frame
The Frame class extends Window to define a main application window that can have amenu bar.
Sandhya.Kishan
- Jul 26th, 2012
A window is a Container and has BorderLayout by default.
A frame is a movable window with title bar and close button,usually it contains Panels. Its derived from a window.
Frame can be part of the window but window can not part of frame. -
Which class is extended by all other classes
The Object class is extended by all other classes.
Sandhya.Kishan
- Jun 2nd, 2012
The object class is the super class of each and every class and henae it is extended by all other classes.
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Can an object be garbage collected while it is still reachable
A reachable object cannot be garbage collected. Only unreachable objects may begarbage collected..
Sandhya.Kishan
- Jun 14th, 2012
No, reachable object cannot be garbage collection ,only when the object becomes unreachable in gets collected in garbage collector.
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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 aFont object.
Sandhya.Kishan
- Jul 24th, 2012
The Font class maps the characters of the language to their respective glyphs.
The FontMetrics provides access to attributes of Fontobjects, things such as char width, char height, which help in drawing the fonts on the screen. -
How is rounding performed under integer division
The fractional part of the result is truncated. This is known as rounding toward zero.
Sandhya.Kishan
- Jul 25th, 2012
By truncating the fractional part of the result we are rounding the result and this is called as rounding towards zero.
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What happens when a thread cannot acquire a lock on an object
If a thread attempts to execute a synchronized method or synchronized statement and isunable to acquirean object's lock, it enters the waiting state until the lock becomes available.
Sandhya.Kishan
- Jul 26th, 2012
When a thread cannot acquire a lock on an object thread enters the waiting state until the lock becomes available .
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What classes of exceptions may be caught by a catch clause
A catch clause can catch any exception that may be assigned to the Throwable type. Thisincludes the Errorand Exception types.
Sandhya.Kishan
- Jul 21st, 2012
An exception which may be assigned to the Throwable type including the Error and Exception types are caught by catch clause.
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What is the SimpleTimeZone class
The SimpleTimeZone class provides support for a Gregorian calendar.
Sandhya.Kishan
- May 17th, 2012
The concrete subclass of TimeZone that represents a time zone which is use support the Gregorian calendar is called as a simple time zone class.Historical changes are not handled by this class.
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What is the Map interface
The Map interface replaces the JDK 1.1 Dictionary class and is used associate keys withvalues.
Sandhya.Kishan
- May 17th, 2012
Map interface represents a mapping between a key and a value without duplicate keys.The maps contents are viewed as a set of keys, collection of values, or set of key-value mappings. Map permits null ...
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For which statements does it make sense to use a label
The only statements for which it makes sense to use a label are those statements that canenclose a break orcontinue statement.
Sandhya.Kishan
- Jul 21st, 2012
For statements which are enclosed by a break or a continue statement makes sense to use a label statement.
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