SDSU CS 696 Emerging Technologies: Java Distributed Computing
Spring Semester, 1999
Java on Rohan
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San Diego State University -- This page last updated 01-Feb-99

Contents of Doc 4, Java on Rohan


rohan system administrator
rohan file system

Doc 4, Java on Rohan Slide # 2

Some Java Information

Java on Rohan

Version of Java available:

JDK 1.0.2
Compatible with Netscape 3.0 browsers
For applets
JDK 1.1.6
Should be replaced by JDK 1.1.7 soon

JDK 1.1.7
Should be on rohan soon.
This is the last release of JDK 1.1.X
JDK 1.2 (also called Java 2)
API is at least twice the size of the 1.1.x API

Default Version

/opt/java points to the current "safe" version of java on rohan

Currently this point to JDK 1.2

Doc 4, Java on Rohan Slide # 3
Using a Version of Java

Add to your path the location of the java bin directory of the version you wish to use
1.2 (Java 2)
1.2 (Java 2 )

As new versions of Java are released older versions of the JDK will be removed from rohan. If you hard code in your path a particular jdk, when it is removed, you will have to modify your path. /opt/java was created to allow users to avoid having to change their environments each time a new version of jdk is released. You can use a version of java not on your path by explicitly referencing it in the command line:

/opt/jdk1.0.2/bin/java     foo

If you do this a lot alias the command

Doc 4, Java on Rohan Slide # 4

SDSU Java Library

The SDSU Java library contains ~100 classes, some of which may be useful in your assignments

The library is on rohan and moria and is free

Documentation is at:

You can also download the library from that URL

To use the library you need to know how to use packages. See for information about using packages.

Doc 4, Java on Rohan Slide # 5

Classpath and SDSU Java Lib

Set the CLASSPATH environment variable to point to locations that contain java packages that you with to use. There is no need to include the location of the standard Java packages, it is done for you by java.

The SDSU Java library has been installed as a standard extension to jdk1.2 on rohan and moria. This means that you do not need to include the SDSU Java Library in your classpath to use the SDSU Java library on rohan or moria. In fact, even if you include the SDSU Java library in your path, the version referenced in your path will not be used. If you are using pre-JDK 1.2 java’s the following classpath will access the SDSU Java library.
setenv CLASSPATH '.:/usr/local/lib/java'

Doc 4, Java on Rohan Slide # 6
Java GUI Applications & NCD Terminals

There are several problems running a java GUI based application on the NCD terminals on campus.

First, on some accounts an AWT based program will not display on NCD terminals. This does not happen all the time. It does not seem to happen with JDK 1.2, but this could be from a small test sample. The problem is with the old version of the NCD software (3.x) running on the NCD terminals. Reports are that version 5 of the NCD software fixes the problem, however NCD does not support the version of the terminals in BAM and in E301. A few terminals in the library can run version 5. This does not affect applets running in a browser, but does affect applets running in the appletviewer. The fix for this problem is:


   xstdcmap -all

at the shell prompt before you run a java application that uses AWT and have it display on an NCD X-terminal in the BAM labs. This does not work with some window managers like fvwm.

Second, in JDK 1.1.6 and 1.2 the window coordinate system on the NCD is off by 10-30 pixels

You need add 10-30 pixels to the y coordinate system so that the top of the window is accessible

Doc 4, Java on Rohan Slide # 7


Using Javadoc

There are three steps in creating java documentation using javadoc. First there is inserting the proper comments in your source code. Second is running javadoc. There are some problems with javadoc in JDK 1.1.x. These have been fixed in JDK 1.2. For more information about using javadoc see:


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1999 SDSU & Roger Whitney, 5500 Campanile Drive, San Diego, CA 92182-7700 USA.
OpenContent license defines the copyright on this document.

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