RUE is intended to be used as a general, local or remote, monitoring tool for any Java based server such as Tomcat, Tyrex, Enhydra, JBoss, JOnAS, etc. RUE is written in 100% Java, and features pluggable samplers and sensors, data visualization plug-ins, configurable data history, output of HTML reports, a standard AWT GUI, JNDI-based sensor lookups, and a simple API for pooling, aggregation, and averaging.
Source code of a server that looks up MX records. The server can be queried using a plain simple tcp/ip socket. The server calls the UNIX porgram "dig" do the querry for it. Reason of creation: for some languages its difficult to find the MX record that belongs to a domain. Also its a nice example on how to call a program from Java.