7. Define the “integrity rules”? There are two Integrity rules. Entity Integrity: States that “Primary key cannot have NULL value” […]
181. What method must be implemented by all threads? All tasks must implement the run() method, whether they are a
175. What is a Java package and how is it used? A Java package is a naming context for classes
169. What is the difference between a Scrollbar and a ScrollPane? A Scrollbar is a Component, but not a Container.
163. Which arithmetic operations can result in the throwing of an ArithmeticException? Integer / and % can result in the
157. What is a compilation unit? A compilation unit is a Java source code file. 158. What interface is extended
151. What is the difference between the File and RandomAccessFile classes? The File class encapsulates the files and directories of
45. What is the Set interface? The Set interface provides methods for accessing the elements of a finite mathematical set.
139. What Checkbox method allows you to tell if a Checkbox is checked? getState(). 140. What state is a thread
127. What is casting? There are two types of casting, casting between primitive numeric types and casting between object references.
121. Which class is the immediate superclass of the Container class? Component. 122. If a method is declared as protected,
103. What restrictions are placed on the values of each case of a switch statement? During compilation, the values of
97. Is &&= a valid Java operator? No. It is not a valid java operator. 98. Name the eight primitive
97. Is &&= a valid Java operator? No. It is not a valid java operator. 98. Name the eight primitive
79. When can an object reference be cast to an interface reference? An object reference be cast to an interface
67. How are Java source code files named? A Java source code file takes the name of a public class
61. What method is invoked to cause an object to begin executing as a separate thread? The start() method of
49. What invokes a thread’s run() method? After a thread is started, via its start() method or that of the
37. What are order of precedence and associativity, and how are they used? Order of precedence determines the order in
31. Name three Component subclasses that support painting. The Canvas, Frame, Panel, and Applet classes support painting. 32. What value
25. What are wrapped classes? Wrapped classes are classes that allow primitive types to be accessed as objects. 26. Does
7. What’s new with the stop(), suspend() and resume() methods in JDK 1.2? The stop(), suspend() and resume() methods have
1. What is a transient variable? A transient variable is a variable that may not be serialized. 2. Which containers
1. What is a transient variable? A transient variable is a variable that may not be serialized. 2. Which containers
97. Difference between Swing and Awt? AWT are heavy-weight componenets. Swings are light-weight components. Hence swing works faster than AWT.
