topic Re: Java Question in Operating System - Linux

Java Question

Kyle D. Harris — Tue, 03 Feb 2004 09:05:26 GMT

I'm setting up a server and in a step i got off a web page i'm going by it says this:

Compile the source into a class file as follows:

javac -classpath /usr/local/jakarta-tomcat/common/lib/servlet.jar HelloWorld.java
This will create a file called HelloWorld.class. Copy the HelloWorld.class file to the /home/tomcat/your_application/WEB-INF/classes directory.

*** When i do this i get a "bash: javac: command not found "...... why is this? The site i'm going off of is spefiically for configuring apache and tomcat for RH 9.0 which i have. Thanks ..

Re: Java Question

Kyle D. Harris — Tue, 03 Feb 2004 09:07:56 GMT

I just read something on a board.. Do i need the Java 2 sdk installed to be able to do this javac command?

Re: Java Question

Steven E. Protter — Tue, 03 Feb 2004 09:32:12 GMT

At the very least it appears you need Java Run Time which is a subset of JDK.

SEP

Re: Java Question

Kyle D. Harris — Tue, 03 Feb 2004 09:35:21 GMT

I'm having alot of trouble trying to find somewhere to download this Java 2 SDK ... I'm looking around on sun.java.com but haven't seen anything for RH 9.0 yet. If anybody can send a direct link that'd be great. I'll keep looking. Thanks.

Re: Java Question

Jerome Henry — Tue, 03 Feb 2004 09:36:31 GMT

Yes,
you need java run time to interpret java code as a client, and java sdk to compile your own java progs.
J

Re: Java Question

Jerome Henry — Tue, 03 Feb 2004 09:38:03 GMT

http://java.sun.com/j2se/1.4.2/download.html
Go for sdk part.

J

Re: Java Question

Kyle D. Harris — Tue, 03 Feb 2004 09:41:28 GMT

I just did a "find / -name *sdk* " and i came up with 'j2sdk1.4.1' which i have already installed.

If that is already installed then what part do i still need? The JRE download??? Thanks.

Re: Java Question

Mark Grant — Tue, 03 Feb 2004 10:00:41 GMT

Kyle, do you have a "javac" anywhere in that directory?

If so, just add that directory to your PATH or type the full path name to "javac"

Regards

Re: Java Question

Kyle D. Harris — Tue, 03 Feb 2004 10:03:23 GMT

Hmm actually Mark, in that directory after j2sdk1.4.1/bin there is javac in there. I'll try putting it in my path.

Re: Java Question

Kyle D. Harris — Tue, 03 Feb 2004 10:09:16 GMT

I'm not real experienced so correct me if I'm wrong but you mean like this:

*prompt*# /usr/java/j2sdk1.4.1/bin/javac -classpath /usr/local/jakarta-tomcat/common/lib/servlet.jar HelloWorld.java

?? Thanks for the help.

Re: Java Question

Kyle D. Harris — Tue, 03 Feb 2004 10:13:56 GMT

After running what i posted in my last post, it paused for a second and gave this:

error: cannon read: HelloWorld.java
1 error

Re: Java Question

Martin P.J. Zinser — Tue, 03 Feb 2004 11:13:08 GMT

Hello Kyle,

to clarify some terminology. Java is a programming language starting from text source code, which is compiled to a bytecode format, which is then executed. If all you want to do is execute programs that other people already compiled you only need the part interpreting the bytecode. This is the so called runtime environment or JRE. If you want to compile text source code yourself you need a SDK (software developers kit). The SDK is a superset of the JRE, i.e. all the functionality of the JRE is also part of the SDK.

Try to put the bin directory into your path for ease of use. Using this will cut down the overlong commands you have now considerably.

As for the last error you are getting, are you sure you have a HelloWorld.java in your current working directory?

Greetings, Martin

Re: Java Question

Bruce Copeland — Tue, 03 Feb 2004 11:14:16 GMT

Kyle:

Make sure that HelloWorld.java is located in the directory from which you are executing the javac command. Also make sure that the permissions on the file give read access. If HelloWorld.java is located somewhere else, you either need to cd to that directory before giving the javac command, or you need to add a -sourcepath option specifying where your source is located. (Type javac -h to get more detail about command options.)

Bruce

Re: Java Question

Olivier Drouin — Tue, 03 Feb 2004 11:18:11 GMT

in /etc/profile or ~/.profile, Add:

PATH=$PATH:/usr/java/j2sdk1.4.1/bin
export PATH

I'd say you get the last error because you .java was not in the same dir that you issued you command.

Re: Java Question

Kyle D. Harris — Tue, 03 Feb 2004 11:20:08 GMT

Problem Solved. I wasn't in the directory where my HelloWorld.java was in. OOps! Thanks to all who responded.

Kyle