-
What invokes a thread's run() method
After a thread is started, via its start() method or that of the Thread class, the JVMinvokes the thread'srun() method when the thread is initially executed.
Sandhya.Kishan
- May 11th, 2012
A thread starts its process by invoking the start() method, this start() method invokes the run() method.
-
Name three subclasses of the Component class
Box.Filler, Button, Canvas, Checkbox, Choice, Container, Label, List, Scrollbar, orTextComponent
Sandhya.Kishan
- Apr 14th, 2012
The three subclasses of component classes are Canvas class,panel class and applet class.
-
What is the GregorianCalendar class
The GregorianCalendar provides support for traditional Western calendars.
Sandhya.Kishan
- Apr 24th, 2012
The GregorianCalendar class is a standard calendar which is supported by java.It contains constructors like GregorianCalendar() representing the moment it was created, the GregorianCalendar(int year, ...
-
Which Container method is used to cause a container to be laid out andredisplayed
Validate()
Sandhya.Kishan
- Apr 20th, 2012
The Validate() method is used to cause a container to be laid out anderdisplay.
-
What is the purpose of the Runtime class
The purpose of the Runtime class is to provide access to the Java runtime system.
Sandhya.Kishan
- Jun 2nd, 2012
The runtime class provides access to the java runtime system, it provides runtime information memory availability, invoking the garbage collector.It provides facilities such as Reading data through key board,Running non-java programs from within a java application etc.
-
How many times may an object's finalize() method be invoked by the garbagecollector
An object's finalize() method may only be invoked once by the garbage collector.
Sandhya.Kishan
- Apr 20th, 2012
Only once the garbage collector can invoke the objects finalize() method.
-
What is the purpose of the finally clause of a try-catch-finally statement
The finally clause is used to provide the capability to execute code no matter whether ornot an exception isthrown or caught.
Sandhya.Kishan
- Jul 24th, 2012
The purpose is that,when an exception is caught during program execution,code written in finally clause will be executed ,irrespective of what type of error has occurred.
-
What is the argument type of a program's main() method
A program's main() method takes an argument of the String[] type.
-
Which Java operator is right associative
The = operator is right associative.
-
Can a double value be cast to a byte
Yes, a double value can be cast to a byte.
Sandhya.Kishan
- May 11th, 2012
Any data type can be typecasted to any other data type and hence we can type cast a double value to a byte.
-
What must a class do to implement an interface
It must provide all of the methods in the interface and identify the interface in itsimplements clause.
Sandhya.Kishan
- Jul 23rd, 2012
A class should provides the definition to all the methods declared in the interface to implement an interface.
-
What method is invoked to cause an object to begin executing as a separatethread
The start() method of the Thread class is invoked to cause an object to begin executing asa separate thread.
Sandhya.Kishan
- Jun 2nd, 2012
To cause an object to begin executing as a separate thread we should invoke the start() method present in the thread class.
-
Name two subclasses of the TextComponent class
TextField and TextArea
-
Which containers may have a MenuBar
Frame
-
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.
-
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);
-
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.
-
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.
-
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.
-
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 ...
Java Interview Questions
Ans