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.
You can set the proxy host through the command line. Depending on your network configuration, you might also need to set the proxy port. If necessary, ask your system administrator for the name of the proxy host on your network.
java -Dhttp.proxyHost=proxyhost [-Dhttp.proxyPort=portNumber] URLReader
java -Dhttp.proxyHost=proxyhost [-Dhttp.proxyPort=portNumber] URLReader