The Java Tutorials have been written for JDK 8. Examples and practices described in this page don't take advantage of improvements introduced in later releases and might use technology no longer available.
See Java Language Changes for a summary of updated language features in Java SE 9 and subsequent releases.
See JDK Release Notes for information about new features, enhancements, and removed or deprecated options for all JDK releases.
This section explains how to compile and run a Swing application from the command line. For information on compiling and running a Swing application using NetBeans IDE, see Running Tutorial Examples in NetBeans IDE. The compilation instructions work for all Swing programs applets, as well as applications. Here are the steps you need to follow:
You can download the latest release of the JDK for free from http://www.oracle.com/technetwork/java/javase/downloads/index.html.
You can use a simple program we provide, called HelloWorldSwing, that brings up the GUI shown in the figure below. The program is in a single file,
HelloWorldSwing.java
. When you save this file, you must match the spelling and capitalization of its name exactly.
The HelloWorldSwing.java
example, like all of our Swing tutorial examples, is created inside a package. If you look at the source code, you see the following line at the beginning of the file:
package start;
This means you must put the HelloWorldSwing.java
file inside of a start
directory. You compile and run the example from the directory above the start
directory. The tutorial examples from the Using Swing Components lesson are inside of a components
package and the examples from the Writing Event Listeners lesson are inside a events
package, and so on. For more information, you might want to see the
Packages
lesson.
Your next step is to compile the program. To compile the example, from the directory above the
HelloWorldSwing.java
file:
javac start/HelloWorldSwing.java
If you prefer, you may compile the example from within the start
directory:
javac HelloWorldSwing.java
but you must remember to leave the start
directory to execute the program.
If you are unable to compile, make sure you are using the compiler in a recent release of the Java platform. You can verify the version of your compiler or Java Runtime Environment (JRE) using these commands
javac -version java -version
Once you've updated your JDK, you should be able to use the programs in this trail without changes. Another common mistake is installing the JRE and not the full Java Development Kit (JDK) needed to compile these programs. Refer to the Getting Started trail to help you solve any compiling problems you encounter. Another resource is the Troubleshooting Guide for Java™ SE 6 Desktop Technologies.
After you compile the program successfully, you can run it. From the directory above the start
directory:
java start.HelloWorldSwing