Java voice chat server

[JavaLearner]

Ok im trying to make a new chat server , just a little project for me to learn and have fun at the same time ..
At the moment im trying to find a program that will compile java files ..
im really starting from nothing here so ill show you the info read me i got with the java aplet files .

This is what it said

If you dont know java and still want to use this code..
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Java files are not script and need to be compiled.
for example To compile java files you use: javac org.multichat.ChatClient.java
To run java files you use: java org.multichat.ChatClient



How to create and sign jar's with certificates
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keytool -genkey -alias signFiles -keypass kpi135 -keystore susanstore -storepass ab987c
jarsigner -keystore susanstore -signedjar svoicechat.jar voicechat.jar signFiles
You will be prompted for the store password (ab987c) and the private key password (kpi135).
keytool -export -keystore susanstore -alias signFiles -file SusanJones.cer


To run it on your web page
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0) compile all the files, You need javas development kit for that.
1) generate and sign a jar file you need javas development kit for that
2) change the voicechat.html host field to your java servers ip address or name
3) run org.multichat.server.ChatServer.java <--- this is the server for the chat


If you could point me in the right place or infact any info will help lol