Three-tier Example (MCS-270, Spring 2003)

Introduction

This page describes a Three-tier example that Max set up using Java's RMI technology. To see the JavaSoft's more detailed explanation, go to the Getting Started link at the their webpage JavaTM Remote Method Invocation (RMI)

Necessary files

Following are the files you need:

• An html file which calls the applet: genedFinder.html

• Interface between client and server:
  • Server.java
  • Conflict.java
  • Course.java

• Clients:
  • Textual program: TestClient.java
  • GUI applet: Finder.java

• The server: ServerImpl.java

Following is a file describing the database:

• An SQL file creating the database tables and a sample query of the forme used in the Java program: tables-query.sql

Deployment process

Following is the process I go through to get the applet running (assuming that you have the three java files in some source-file directory, and the html file in some accessible place in your www-docs):

1. Same as the first step in Two-tier Example (courtesy JavaSoft(TM)) , so not necessary if you have already done it.

2. Same as the second step in Two-tier Example (courtesy JavaSoft(TM)) , so not necessary if you have already done it.

3. Save the six java files above in some source-file directory. Go to that directory and issue the following command to compile the java files to the appropriate directory:

            javac -d ~/public_html/codebase *.java
   

4. Set your classpath:

            setenv KARL ~karl
            setenv CLASSPATH $HOME/public_html/codebase:$KARL/public/mcs270/psql-movies/postgresql.jar:.
   

5. Run rmic to create skeletons/stubs:

            rmic -d ~/public_html/codebase edu.gac.karl.gened.ServerImpl
   

6. Start the server (you must issue this command from the serving computer, which must also have its CLASSPATH set as above):

            java -Djava.rmi.server.codebase=http://kilpinen.mcs.gac.edu/~karl/codebase/ \
                 -Djava.security.policy=$HOME/public_html/policy \
                 edu.gac.karl.gened.ServerImpl
   

7. Click on the link above for the running version of the applet

Notice