This paper describes wildcards, a new language construct designed to increase the ? exibility of object-oriented type systems with parameterized classes. Based on the notion of use site variance, wildcards provide a type safe abstraction over diferent instantiations of parameterized classes, by using ‘?’ to denote unspecifed type arguments. Thus they essentially unify the distinct [...]

This tutorial is designed to assist Java TM developers who need to extract information from a database and place it into an XML document.
The tutorial assumes that you are already familiar with Java and XML in general, and the Document Object Model (DOM) in particular. You should be familiar with Java programming, but prior knowledge [...]

JDBC, often known as Java Database Connectivity, provides a Java API for updating and querying relational databases using Structured Query Language (SQL). JDBC is now at version 2.0, although many databases don’t as yet support all of the JDBC 2.0 features!.
Every JDBC program is made up of thefollowing 4 steps:
*Open a connection to the DB
*Execute [...]

The Java™ Programming Language course provides students with information about the syntax of the Java programming language; object-oriented programming with the Java programming language; and creating graphical user interfaces (GUIs), exceptions, file input/output (I/O), and threads and networking. Programmers familiar with object oriented concepts can learn how to develop Java technology applications. The course uses [...]

* Making instance variables public should be avoided, except when using the class as a data structure without behavior.
* Avoid using an object to access a class (static) variable ormethod. Use a class name instead.
* Numerical constants (literals) should not be coded directly,except for -1, 0, and 1, which can appear in a for loop [...]

This article discusses and compares tools for building Graphical User Interfaces (GUIs) in Java. It describes experiences and results in trying to find tools for rapid development of Java GUIs.
One of the key decisions in determining how your forms will look, and how easy it will be to create and maintain them, is what layout [...]

The Java Programming Language course provide students with information about the syntax of the Java programming language; object oriented programming with the Java programming language; creating graphical user interfaces (GUIs), exceptions, file input/output (I/O), and threads; and networking. Programmers familiar with object-oriented concepts can learn how to develop Java technology applications. The course features the [...]

Many vendors and customers are now looking for easy database access for Java applications. Since Java is robust, secure, easy to use, easy to understand, and automatically downloadable on a network, it is an excellent language basis for the development of database applications. It offers many advantages over C, C++, Smalltalk, BASIC, COBOL, and 4 [...]

Java accesses relational databases, such as Oracle and MySQL, through JDBC classes. A manager class which oversees the process is provided with the Java distribution, but you’ll also need to obtain a driver class to talk to the specific database of your choice. Using MySQL as an example, this module takes you through the sourcing, [...]

This tutorial walks you through the task of building a graphical Java applet. Along the way, you’ll learn Java syntax and work with Java class libraries. It requires that you know some object oriented programming.