Q114. What is the difference between the Reader/Writer class hierarchy and the InputStream/OutputStream classhierarchy?
The Reader/Writer class hierarchy is character-oriented, and the InputStream/ OutputStream class hierarchy is byte-oriented.
Q115. 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. This includes the Error and Exception types.
Q116. If a class is declared without any access modifiers, where may the class be accessed?
A class that is declared without any access modifiers is said to have package access. This means that the class can only be accessed by other classes and interfaces that are defined within the same package.
Q117. What is the SimpleTimeZone class?
The SimpleTimeZone class provides support for a Gregorian calendar.
Q118. What is the Map interface?
The Map interface replaces the JDK 1.1 Dictionary class and is used associate keys with values.
Q119. Does a class inherit the constructors of its superclass?
A class does not inherit constructors from any of its superclasses.
Q120. 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 can enclose a break or continue statement.
Q121. What is the purpose of the System class?
The purpose of the System class is to provide access to system resources.
Q122. Which TextComponent method is used to set a TextComponent to the read-only state?
setEditable()
Q123. 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.
Q124. Is &&= a valid Java operator?
No, it is not.
Q125. Name the eight primitive Java types?
The eight primitive types are byte, char, short, int, long, float, double, and boolean.
Q126. Which class should you use to obtain design information about an object?
The Class class is used to obtain information about an object's design.
Q127. What is the relationship between clipping and repainting?
When a window is repainted by the AWT painting thread, it sets the clipping regions to the area of the window that requires repainting.
Q128. Is "abc" a primitive value?
The String literal "abc" is not a primitive value. It is a String object.
Q129. What is the relationship between an event-listener interface and an event-adapter class?
An event-listener interface defines the methods that must be implemented by an event handler for a particular kind of event. An event adapter provides a default implementation of an event-listener interface.
Q130. What restrictions are placed on the values of each case of a switch statement?
During compilation, the values of each case of a switch statement must evaluate to a value that can be promoted to an int value.
Q131. What modifiers may be used with an interface declaration?
An interface may be declared as public or abstract.
Q132. Is a class a subclass of itself?
A class is a subclass of itself.
Q133. What is the highest-level event class of the eventdelegation model?
The java.util.EventObject class is the highest-level class in the event-delegation class hierarchy.
Q134. What event results from the clicking of a button?
The ActionEvent event is generated as the result of the clicking of a button.
Q135. How can a GUI component handle its own events?
A component can handle its own events by implementing the required event-listener interface and adding itself as its own event listener.
Q136. What is the difference between a while statement and a do statement?
A while statement checks at the beginning of a loop to see whether the next loop iteration should occur. A do statement checks at the end of a loop to see whether the next iteration of a loop should occur. The do statement will always execute the body of a loop at least once.
Q137. How are the elements of a GridBagLayout organized?
The elements of a GridBagLayout are organized according to a grid. However, the elements are of different sizes and may occupy more than one row or column of the grid. In addition, the rows and columns may have different sizes.
Q138. What advantage do Java's layout managers provide over traditional windowing systems?
Java uses layout managers to lay out components in a consistent manner across all windowing platforms. Since Java's layout managers aren't tied to absolute sizing and positioning, they are able to accomodate platform-specific differences among windowing systems.
Q139. What is the Collection interface?
The Collection interface provides support for the implementation of a mathematical bag – an unordered collection of objects that may contain duplicates.
Q140. What modifiers can be used with a local inner class?
A local inner class may be final or abstract.
Q141. What is the difference between static and non-staticvariables?
A static variable is associated with the class as a whole rather than with specific instances of a class. Non-static variables take on unique values with each object instance.
Q142. What is the difference between the paint() and repaint() methods?
The paint() method supports painting via a Graphics object. The repaint() method is used to cause paint() to be invoked by the AWT painting thread.
Q143. 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 a local file system.
Q144. Can an exception be rethrown?
Yes, an exception can be rethrown.
Q145. Which Math method is used to calculate the absolute value of a number?
The abs() method is used to calculate absolute values.
Q146. How does multithreading take place on a computer with a single CPU?
The operating system's task scheduler allocates execution time to multiple tasks. By quickly switching between executing tasks, it creates the impression that tasks execute sequentially.
Q147. When does the compiler supply a default constructor for a class?
The compiler supplies a default constructor for a class if no other constructors are provided.
Q148. When is the finally clause of a try-catch-finally statement executed?
The finally clause of the try-catch-finally statement is always executed unless the thread of execution terminates or an exception occurs within the execution of the finally clause.
Q149. Which class is the immediate superclass of the Container class?
Component
Q150. If a method is declared as protected, where may the method be accessed?
A protected method may only be accessed by classes or interfaces of the same package or by subclasses of the class in which it is declared.
Q151. How can the Checkbox class be used to create a radio button?
By associating Checkbox objects with a CheckboxGroup.
Q152. Which non-Unicode letter characters may be used as the first character of an identifier?
The non-Unicode letter characters $ and _ may appear as the first character of an identifier
Q153. What restrictions are placed on method overloading?
Two methods may not have the same name and argument list but different return types.
Q154. What happens when you invoke a thread's interrupt method while it is sleeping or waiting?
When a task's interrupt() method is executed, the task enters the ready state. The next time the task enters the running state, an InterruptedException is thrown.
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