Example: Running a Java applet using proxy support
The following example shows you the steps to run a Java applet
using proxy support.
- Choose a machine to act as the proxy server. Applets can
initiate network connections only to the machine from which they
were originally downloaded; therefore, it works best to run the
proxy server on the same machine as the HTTP server. The Java
environment and CLASSPATH on the proxy server machine should
include the jt400.jar file.
- Start the proxy server on this machine by typing:
java com.ibm.as400.access.ProxyServer -verbose
Specifying verbose will allow you to monitor when the client
connects and disconnects.
- Applet code needs to be downloaded before it runs so it is best
to reduce the size of the code as much as possible. The AS400ToolboxJarMaker can reduce the
jt400Proxy.jar significantly by including only the code for
the components that your applet uses. For instance, if an applet
uses only JDBC, we can reduce the jt400Proxy.jar file to
include the minimal amount of code by running:
java utilities.AS400ToolboxJarMaker -source jt400Proxy.jar
-destination jt400ProxySmall.jar -component JDBC
- The applet must set the value of the
com.ibm.as400.access.AS400.proxyServer system property to be
the name of your proxy server. A convenient way to do this for
applets is using a compiled Properties class (Example). Compile this
class and place the generated Properties.class file in the
com/ibm/as400/access directory (the same path your html file
is coming from). For example, if the html file is
/mystuff/HelloWorld.html, then Properties.class should be in
/mystuff/com/ibm/as400/access.
- Put the jt400ProxySmall.jar in the same directory as
as the html file (/mystuff/ in step 4).
- Refer to the applet like this in your HTML file:
<APPLET archive="jt400Proxy.jar, Properties.class"
code="YourApplet.class" width=300 height=100>
</APPLET>