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.
Java applets, like other Java programs, can use the API defined in the java.net
package to communicate across the network. A Java applet can communicate with server applications that run on the same host as the applet. This communication does not require any special setup on the server.
When the applet is deployed to a web server, use the Applet
getCodeBase
method and the java.net.URL
getHost
method to determine which host the applet came from, as follows:
String host = getCodeBase().getHost();
If the applet is deployed locally, the getCodeBase
method returns null. Use of a web server is recommended.
After you have the correct host name, you can use all the networking code that is documented in the Custom Networking trail.
For an example of implementing an applet that is a network client, see Network Client Applet Example.