Network administrators make use of proxy servers to enhance the security oftheir networks. A proxy server can be seen as a service that managesconnections between the internet and an internal network. If your network issitting behind a proxy server, your Java application should know thatinternet calls will go through a proxy. It should also know the name of theproxy server, as well as the port at which the proxy server waits forinternet calls. To provide this information to your Java application you caneither have your application code set some system properties, as in:

 System.getProperties().put( "proxySet", "true" );System.getProperties().put( "proxyHost", "some_proxy" );System.getProperties().put( "proxyPort", "8080" );

or set the relevant system properties when you launch your application fromthe command prompt, as in:

 java -DproxySet=true -DproxyHost=some_proxy -DproxyPort=8080 SomeClass