NetRexx User's Guide, version 2.02
Copyright (c) IBM Corporation, 2001. All rights reserved. ©
Draft of 22 May 2001
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Installing for Visual J++

(Many thanks to Bill Potvin and Bernhard Hurzeler for the details in this section.)

Here's how to install NetRexx for use with Visual J++:

  1. Copy the following file into the [java_root]\Lib directory:
    For example, if [java_root] is at E:\Java:
      C:\>copy NetRexxC.jar E:\Java\Lib
  2. Similarly, copy the nrc.bat and NetRexxC.bat files to the [java_root]\Bin directory.
  3. Add the jar file explicitly to the CLASSPATH:
      C:\>set CLASSPATH=%CLASSPATH%;[java_root]\Lib\NetRexxC.jar;
    For example, if [java_root] is E:\Java, your CLASSPATH might then look like this:
    Under Windows NT 4.0 and Windows 2000 this can be done using Start, Settings, Control Panel, System, Environment tab, System Variables, and clicking on CLASSPATH.

Using NetRexx with Visual J++

Using NetRexx with J++ is very similar to using it with other Java development kits; the main difference is in the command names:
  1. Use the J++ jview command to invoke the NetRexx translator to convert a NetRexx program (e.g., hello.nrx) into a Java program (
    Note that some versions of the jview package do not provide a file by default, but the NetRexx compiler needs this to determine information about classes that you use. If this is the case, you will get a class not found error for java.lang.Object. In this case, run the command
      clspack -auto
    from an MS-DOS prompt to create the file.
    When running the NetRexx compiler, you must specify the -nocompile option to NetRexx in order to prevent it from trying to invoke the Java toolkit compiler javac (which isn't in the MicroSoft J++ classes).
    For example, if hello.nrx is in the current directory:
      jview hello -nocompile
    The result of this step should be a Java source file called
  2. Use the J++ ‘jvc’ command to compile the Java source file:
    The result of this step should be a Java class file called hello.class.
  3. Execute the class file with the J++ command jview:
      jview hello
  4. Note that some earlier versions of jview fail with an exception (an ArrayIndexOutOfBoundsException in RexxUtil.translate) when compiling hello.nrx. This is due to a bug in the jview JIT;[1]  the workaround is to turn the JIT off.

Note that all the commands above probably have to be typed exactly as shown (Java is very case-sensitive). The supplied NetRexxC.bat can be modified to work with the above commands by using jview instead of the java command and adding the jvc step.

[1] Just In Time compiler.

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