Java: Most Popular Articles
Learn how to generate random numbers using the java.util.Random class.
The use of variables is key to any program. Learn how to declare and initialize variables in Java.
Throughout the lifetime of a variable its value might change many times. But what if you know the value will never change? Or more importantly you want to make sure it can't change? This is when you need to use a constant.
Cannot Find Symbol is a compile-time error.
An example Java class for building a simple GUI application. This program corresponds to the Coding a Simple Graphical User Interface - Part I
This program creates a simple calculator that performs addition and subtraction. It highlights how to implement the ActionListener interface in three different ways.
In object-oriented programming sometimes it's necessary to provide access to the private fields of an object. The use of accessors and mutators are a way to enable that access.
Follow these steps if you want to find out if your computer is 32-bit or 64-bit.
Using standard Java naming conventions will increase the readability of your code and make it easier to maintain.
Are you ready to start programming in Java? Follow this step-by-step tutorial to learn how to write, compile and run Java programs.
When a new instance of an object is created the constructor method is called. Examples of how to create constructor methods in Java are discussed here.
How to use JFrame to create a simple window for a Java application.
Find out what Java is, who created it, and why people choose to program with it.
Follow this step-by-step guide to learn how to design and create an object. Page 6.
Example Java program code for how to make simple message dialog boxes using the JOptionPane class.
Static methods are created using the static keyword.
Use the if-then and if-then-else statements when your program needs to make a simple decision about what to do next.
An example program showing how to use the JTable class
Here you will find a list of words that you cannot use as identifiers in a Java program.
Aggregation is a relationship between two objects that is best described as a
An identifier is simply a name given to a package, class, interface, method, or variable.
Learn how to use the JOptionPane class to make a simple message dialog box
How to make use of command-line arguments in your Java applications.
Example Java program code to make several different types of input dialog boxes using the showInputDialog method of JOptionPane.
Make your first Java download the right one. Step-by-Step instructions on how to download the latest version of the JDK.
A method signature is part of the method declaration. It is the combination of the method name and the parameter list.
Learn about the Unicode standard, a global way to encode the characters that computers use.
OpenJDK is an open source version of the JDK.
An example Java program showing how to use the JProgressBar
The Java language provides eight primitive data types that define simple values a program can use.
Follow this step-by-step tutorial to learn how to write, compile and run Java applets.
How to convert Strings to numbers and back again.
Fields can be shared across all objects of the same type through the use of the static modifier.
Enhance the readability of your programs by using Java comments.
An example program showing how to implement the KeyListener interface.
There are three different types of exceptions a Java application might encounter.
Reached end of file while parsing is a compile time error.
Bring a sense of order to your classes through the use of packages.
Learn how to include the functionality of packaged classes into your programs.
Example Java program code for creating a simple password dialog box.
Sometimes the random numbers to be picked need to be unique.
How to use the ArrayList class. Java.
A Java program to show the String class in action.
An example JavaFX application to show how to build a simple graphical user interface. The interface is the same as those built using Swing in part 1 and NetBeans GuiBuilder in part two.
Learn about object inheritance and how it can be used to create a relationship between objects that share common characteristics.
The ternary operator ?: earns its name because it's the only operator to take three operands.
A look at how to use the GridLayout layout manager.
The association relationship is a way of describing the fact that a class knows about, and holds a reference to another class.
The void keyword denotes that a method does not have a return type.
Find out how to use the showInputDialog method of the JOptionPane class to make different kinds of input dialog boxes.
See if you can debug a piece of code that produces one of the most fundamental Java runtime errors.
In a method call the implicit parameter is the object the method belongs to.
An object is an instance of a class.
An example program to show the DefaultTableModel in action.
When coding in Java it's important to remember that Java is case sensitive. Here are some tips to avoid common case sensitivity pitfalls.
String Literals are used for representing string values in Java code.
A step-by-step guide to manually coding a simple graphical user interface. Part two of this step-by-step shows how to code the same graphical user interface using NetBeans Gui Builder.
Following on from the first article on generating random numbers in Java, find out how to generate random fractional numbers and boolean values.
A variable is a container that holds values that are used in a Java program.
Example code for reading and writing to a binary file one byte at a time.
Example Java code to show how the GridLayout, the BorderLayout and the BoxLayout can be used to make a customizable graphical user interface for a simple calculator.
A class specifies the design of an object.
How to implement the Key Listener Interface, which provides the ability to find out what keys a user is pressing while a graphical component has the focus of the graphical user interface.
The denary (or decimal) numbering system is the most widely used in the world. It has a base of 10 and uses the numerals 0,1,2,3,4,5,6,7,8,9.
Understanding object-oriented programming is fundamental to becoming a truly great Java programmer. The key concepts of objects are discussed in this article.
Example code showing how the GridBagLayout layout manager can be used to position components.
Expressions are essential building blocks of any Java program. They are built using values, variables, operators and method calls.
A look at the JTable class and how it can be used to make simple tables for GUIs
A simple application showing how the CardLayout can be used to switch JPanels.
Conditional operators are used to evaluate a condition that's applied to one or two boolean expressions.
Concatenation describes the operation of joining two strings together.
This example code shows how to simply switch between two JavaFX stylesheets.
How to make use of arrays. Java.
Java handles exception through the use of the try-catch-finally blocks
How to delete, copy and move files using nio.2
Learn how to read bytes from a binary file one byte at a time.
How to create a simple JavaFX FXML application using NetBeans and Scene Builder.
Step-by-Step instructions on how to install the latest version of the JDK.
Scope refers to the lifetime and accessibility of a variable. How large the scope is depends on where a variable is declared.
Example Java program code to show how the JFileChooser class is used to present an open file dialog box and save file dialog box to a user.
A superclass is a class that has been extended by another class.
Whilst learning Java the best way is to compile and run example code. Using multiple classes within a NetBeans project means you can keep all your code examples in one place and try them out independently of each other.
An example program showing how to implement the three mouse event listeners
An example Java program showing a simple application using the BoxLayout.
Compound assignment operators provide a shorter syntax to assign the results of the arithmetic and bitwise operators.
Before you start to learn Java, you need somewhere to write your programs. Here's a guide to using an IDE versus a text editor.
Declaration statements are used to declare variables.
Some classes are designed not to be extended by other classes. Find out how to prevent a class being inherited by another.
The main method is the starting point for the execution of every Java application.
Parameters are the variables that are listed as part of a method declaration.
Use the switch statement when you want your program to chose between a number of alternative options.
An example program to show how to code a BorderLayout layout manager with assigned horizontal and vertical spacing.
The term composition takes on different meanings depending on the subject, and in Java it has its own meaning as well.
Turtles, magic and squares will conspire to test your logic in this exercise.
The ActionListener interface is an event listener for actions performed by some graphical components.
An event listener receives and process events.
Find out about data encapsulation, the most important concept of object-oriented programming.
A literal is a value that can be written directly into Java source code.
An example Java application which allows the user to combine various JOptionPane options to show example dialog boxes.
A basic look at the structure of a very simple Java program. This article gives a beginner a starting place for understanding the way the Java syntax builds to make a Java program.
A common question new developer are faced with, is where do I start when faced with learning the Java language? Here are some tips.
NetBeans is a sophisticated IDE that aims to help developers build any type of application.
If expressions are akin to clauses in the English language, then statements are like sentences.
A step-by-step by guide implementing the MouseListener, MouseMotionListener, and MouseWheelListener event listeners using a simple gui application.
This step-by-step guide shows how to build the simple GUI application created in Coding a Simple Graphical User - Part I using the NetBeans GUI Builder.
A subclass is a class that extends another class.
Example Java code showing the ItemListener event listener in action
Example Java code showing how the ListView and ComboBox JavaFX controls can be used.
An overview of how to use the GridPane to make a table format.
The float data type in Java can be used to store floating point numbers.
Constructor chaining occurs through the use of inheritance.
Example Java program code that shows the two static methods of the JColorChooser class in action to make a color chooser dialog box.
A relational operator compares two operands to determine whether one is greater than, greater than or equal to, less than, less than or equal to the other.
Overloading is the ability to define more than one method with the same name in a class.
Any application providing a secure environment for a user needs to be able to safely obtain the password for that user.
Since Java 7 the version of Java for the Mac OS X now comes from Oracle.
Example Java code for a program which provides a user with options to change the alignment and spacing of components in a FlowLayout layout manager.
A constant is a variable whose value cannot change once it has been assigned.
Can you rewrite this Java code so that there is no longer an infinite loop?
An overview of the BorderLayout layout manager.
Competition in the Robocode arena is fierce. Learn Java by trying to build a robot that will send all the others to the scrap heap!
It’s a way of designing an application that separates data access, business logic and the graphical user interface.
Looking at the JavaFX program structure. Page 2.
The string class provides a few methods for manipulating Strings.
Java 7 Update 45 has been released and the JDK is available to download from Oracle's Java download page. The release notes show this to be a security fix
Things are a little different for Java developers on Mac OS X. Find out how Java fits in with Apple computers.
Example Java code showing how the TreeView JavaFX control is used.
java.lang.NoClassDefFoundError is a runtime error.
Discover how a class can inherit the state and behaviors of another class.
Hexadecimal refers to a numbering system that has a base of 16. This means it uses all the numerals 0,1,2,3,4,5,6,7,8,9 as well as the letters A,B,C,D,E,F for each digit of a number.
Here are the steps to disable (or enable) the Java plugin in a browser.
When a new version of an API is released it's quite common for parts of it to become deprecated.
A look at the table model behind the JTable
A look at the JavaFX ComboBox class.
The String class lets you create and manipulate Strings.
An event typically occurs when a user interacts with a user interface.
Arithmetic operators perform the same basic operations you would expect if you used them in mathematics (with the exception of the percentage sign).
Find out what an exception is and how Java handles them.
Building an interface for a simple calculator program
The most commonly used operator is the assignment operator.
An overview of the Adopt a JSR program
Source code refers to the programming instructions used to create an application.
An overview of the GridBagLayout layout manager.
The arguments that have an operation performed on them by an operator are called operands.
Loops are a way of executing the same code block many times.
Java technology recognizes that developers build different applications based on the differing needs of their users. Discover the different editions of the Java platform available to developers.
A main class is a class that contains a main method
Find out what JavaFX is and what it can be used to create.
An anonymous inner class is a class with no name that will only have one instance created.
How to read and write to a text file one character at a time.