Java Programming Tutorials

Java Programming Tutorials And Articles
  Title / Author Replies
Views Reverse Sort Order
Multi-dimensional arrays Java, as with most languages, supports multi-dimensional arrays - 1-dimensional, 2-dimensional, 3-dimensional, ... This discusses 2-dimensional arrays, but the same principles apply to higher dimensions. 2-dimensional arrays 2-dimensional arrays are usually...
37
561,379
Objects in Java are referred using reference types, and there is no direct way to copy the contents of an object into a new object. The assignment of one reference to another merely creates another reference to the same object. Therefore, a special clone() method exists for all reference...
8
225,015
We can create a thread in Java by extending Thread Class. A better way to create a thread in Java is to implement Runnable interface. A thread can be created by extending Java Thread class also. Now the question arises why implementing Runnable interface is a better approach? Answer is, if the...
4
163,484
1. How can you store a copy of an object at the same time other threads may be changing the object's properties? Choice 1 Override writeObject() in ObjectOutputStream to make it synchronized. Choice 2 Clone the object in a block synchronized on the object and serialize the clone. Choice 3...
23
147,212
Java is an object-oriented language and as said everything in java is an object. But what about the primitives? They are sort of left out in the world of objects, that is, they cannot participate in the object activities, such as being returned from a method as an object, and being added to a...
13
121,143
This article demonstrates how to write a simple Stateful Session Bean. It consists of three POJO's: Remote interface Cart.java, Bean class CartBean.java and EJB client CartClient.java. Prerequisites In order to complete the example application, you should be familiar with the following: *...
7
73,876
An Applet is a small program that can be sent across the Internet and interpreted on a client machine. To give permission for remote access it must be a public class. Typically it is a class that inherits and/or defines a special set of functions needed to run an applet. These are part of the class...
2
65,602
Java's networking classes enable you to implement applications that communicate across a network/remote connection, but the platform also extends into the realm of the Internet and URLs. Java's URL class makes accessing Web resources as easy as accessing a local file. Let's take a look at how you...
13
65,120
LDAP - The Lightweight Directory Access Protocol This directory access protocol which can either act as a gateway to other service or provide service itself. LDAP follows standardized way of managing directory information solutions of X.500. The Lightweight Directory Access Protocol, better...
1
62,768
This is a basic digital clock in Java that works off your operating system time, it works in a multithreaded environment and have coded it to put my own background in. import java.awt.*; import javax.swing.*; import java.util.*; class Clock extends JFrame implements Runnable { ...
6
59,138
Automatic Conversion In Java type conversions are performed automatically when the type of the expression on the right hand side of an assignment operation can be safely promoted to the type of the variable on the left hand side of the assignment. Thus we can safely assign: byte -> short -> int...
0
52,433
Introduction The 'main()' method in Java is referred to the thread that is running, whenever a Java program runs. It calls the main thread because it is the first thread that starts running when a program begins. Other threads can be spawned from this main thread. The main thread must be the...
4
43,124
All the three keywords final, finally and finalize() plays a very important role in JAVA. Final is a keyword used for declaration of variable which cannot be edited, finally is a segment of code used for code cleanup in case of an exception whereas finalize is a method used for object cleanup...
2
40,558
An initialization block is a block of code between braces that is executed before the object of the class is created. As the execution of the initialization block is dependent on the creation of the object we can easily make a guess that it has two types of object. 1. Non static initialization...
1
32,288
The JavaMail API (http://java.sun.com/products/javamail/) is a messaging framework intended to build platform-independent applications that use e-mail messaging. It is included in the J2EE platform and is available as an optional package in J2SE. The API's main purpose is not for transporting,...
0
31,837
I often hear people asking on how to put an image on Java applications, thus here is an example of a painted panel that has an image in the same directory as the application *note* you cant use windows bmp with Java, but once you start creating your own images it's a good time to note that their...
14
29,228
Using Regular Expressions in Java JDK versions 1.4.0 and later have comprehensive support for regular expressions through the standard java.util.regex package. Because Java lacked a regex package for so long, there are also many 3rd party regex packages available for Java. I will only discuss...
13
28,335
Before you can catch an exception, some code somewhere must throw one. Any code can throw an exception: your code, code from a package written by someone else such as the packages that come with the Java platform, or the Java runtime environment. Regardless of what throws the exception, it's always...
0
26,814
Introduction Buffers can be very useful in Java since they speed up I/O operations considerably. Basically a buffer is a space allocated in memory for Bytes, Chars, and other data types to be stored. Buffers are really useful while writing Client/ Server applications. Creating a Buffer A...
4
26,811
Every class has at least one it's own constructor. Constructor creates a instance for the class. Constructor initiates something related to the class's methods. Constructor is the method which name is same to the class. But there are many difference between the method s and the Constructor.In this...
3
26,798