CPI-C for Java
One Internet technology that has generated much attention lately is
Java;, a network-enabled computing environment developed by Sun Microsystems;.
Java is a useful technology for two reasons:
- It is platform-independent, so applications can be written once and run on a variety
of computers.
- It can be dynamically downloaded; that is, code can reside on a server and flow to the
client as needed, thus reducing client installation costs.
IBM created a Java binding to Common Programming Interface for Communications (CPI-C),
an open API for SNA LU 6.2. This improves the suitability of Java for highly reliable
enterprise intranets.
The CPI-C for Java toolkit provides:
- The ability to write a CPI-C for Java application once and run the application on any
platform that supports CPI-C for Java
- The ability to port client-side applications to CPI-C for Java and run with existing
APPC and CPI-C server applications without any change to the server application
- The ability to leverage your existing CPI-C programming skills in this new Java world
JPing Sample Program
JPing is a sample CPI-C Java application which behaves similarly to the ASUITE
"APING" client application.
JPing will exchange data with an APING Server process (APINGD) running either on the
gateway or a workstation.
JPing is run from a command line, and its operation is controlled by the command-line
arguments it is given when started.
The class file JPing.class is included in the Java Archive (JAR) file
CPICJAVA.JAR.
When running the sample, you must tell the Java Runtime Environment (JRE) where to search
for the class file.
The following examples assume that Personal Communications was installed in
C:\Program Files\Personal Communications.
The JRE is installed in the JRE subdirectory, and the JAR
file is in the samples\JPing subdirectory.
The first example runs JPing with the -? option to
display a usage message.
C:\Program Files\Personal Communications>jre\bin\jre -cp .\CPICJAVA.JAR JPing -?
Copyright IBM Corporation 1997. All rights reserved.
U.S. Government Users Restricted Rights - Use, duplication
or disclosure restricted by GSA ADP Schedule Contract with
IBM Corp.
JPing [-s symb_dest] [-n num_iter] [-d data_len]
The "-cp .\CPICJAVA.JAR" option is given to
the JRE to indicate that the search for classes should include
CPICJAVA.JAR in addition to the default places and the
CLASSPATH environment variable.
The next example assumes the user has a CPI-C side info record
"APINGM4" configured.
This example runs JPing with the -s APINGM4 CPI-C
symbolic destination name for 10 iterations:
C:\Program Files\Personal Communications>jre\bin\jre -cp .\CPICJAVA.JAR JPing -s APINGM4 -n 10
-----------------JPing Opening------------------
OS Name = Windows 95
CPI-C Side Info (-s) = APINGM4
Number Iterations (-n) = 10
Data Length (-d) = 2000
Max Buffer (cmembs) = 65535
Allocate Time = 0.05 seconds
Version Exchange Time = 0.66 seconds
Server Error Version: 1
ServerVersion: 2.38
Ping Time = 0.11 seconds
Ping Time = 0.05 seconds
Ping Time = 0.11 seconds
Ping Time = 0.06 seconds
Ping Time = 0.05 seconds
Ping Time = 0.11 seconds
Ping Time = 0.06 seconds
Ping Time = 0.05 seconds
Ping Time = 0.06 seconds
Ping Time = 0.11 seconds
Total Ping Time = 0.77
Average Ping Time = 0.077
-----------------JPing Closing------------------
See Quick Beginnings and Configuration File Reference
for information on how to configure CPI-C Side Information records for APING and JPing.
The supplied sample currently cannot use a Control Point name as the partner LU name,
but you can easily modify it to do so.