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In Java, final is a keyword. It has the following impact on variables,
methods, and classes: If a variable declaration is preceded by the
final keyword, then its value cannot be changed in the program. If in a
method declaration, the method name is preceded by the final keyword,
then that... [read more..]
Generalization defines a is-a-kind of relationship in which one class
shares its structure and/or behavior with one or more other classes.
The concept of generalization in UML is similar to inheritance in Java.
It maps directly to the extends keyword. It is shown by a straight line
originating... [read more..]
A servlet is a small Java program that runs within a Web server. It is
a server-side programming language used to fulfill clients' requests. A
request can be a static page such as an HTML file, or a dynamic request
such as a form submitted. All servlets must implement the Servlet
interface. [read more..]
In Java, a narrowing conversion is also known as an explicit type
conversion or casting. When the destination data type is narrower than
the source data type, an explicit type conversion is required. The
general form of this explicit conversion is given below: (target-type)
value Here,... [read more..]
The setBackground() method is defined by the Component class. It is
used to set the background of an applet's window to a specified color.
The syntax of this method declaration is as follows: void
setBackground(Color newcolor) Here, new color specifies the color. The
Color class... [read more..]
An assignment statement is an expression statement. The statement ends with a semicolon(;). It has the following general form:
var=expression;
The value of var is the value of the expression on the right hand side.
The data type of var must be compatible with the data type of...
[read more..]
LinkedList is a class that extends the AbstractSequentialList class and
implements the List and Queue interfaces. LinkedList is a generic
class. The class declaration is given below: class LinkedList<E>
Here, E specifies the type of objects that the list will hold. It
defines the... [read more..]
In a class hierarchy, when the subclass method has the same name and
signature as its superclass method, the method in the subclass is said
to override the method in the superclass. This phenomenon is known as
method overriding. An example of method overriding is given below:
class... [read more..]
JMS, which stands for Java Message Service also referred to as
Messaging Oriented Middleware (MOM), defines standards for reliable
enterprise messaging. As JDBC provides access to many different
relational databases, in the same way, JMS provides vendor-neutral
access to enterprise messaging... [read more..]
JNDI stands for Java Naming and Directory Interface. It is an API
(Application Program Interface) that allows Java programs to interact
with any naming service and directory service that implements JNDI. [read more..]
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