NetRexx
| Company type | Open source programming language |
|---|---|
| Industry | Software, Programming languages |
| Founded | 1996 |
| Founder | Mike Cowlishaw |
| Headquarters | International |
| Products | NetRexx programming language |
| Owner | Rexx Language Association (since 2011), formerly IBM |
| Website | www |
NetRexx represents an open source adaptation of the REXX programming language tailored to operate on the Java Platform virtual machine. Initially created by IBM, it preserves the traditional REXX syntax without reserved keywords while incorporating object-oriented capabilities aligned with Java’s object model. The language functions both as a compiled and interpreted tool, providing flexibility to utilize either JVM-native data types or the NetRexx runtime library, which offers a Rexx data type that merges string manipulation with arbitrary precision decimal arithmetic.
Designed for close integration with the JVM environment, NetRexx enables straightforward access to existing Java class libraries without requiring additional configuration. Java programmers can also leverage the Rexx class included in the runtime package to enhance string processing within Java-compatible code.
The Rexx Language Association (RexxLA) currently distributes NetRexx free of charge, having assumed responsibility for its maintenance from IBM in 2011 after IBM released the NetRexx 3.00 source code.
History
Mike Cowlishaw began porting Java to OS/2 in 1995 and soon explored executing REXX on the JVM. As one of the earliest alternative JVM languages, NetRexx capitalized on REXX’s status as a pioneering general-purpose scripting language. The first public release, version 0.50, appeared in April 1996 and included runtime classes along with a translator executable for OS/2. The 1.00 release arrived in January 1997 featuring a translator bootstrapped using NetRexx itself.
The August 2000 release of version 2.00 introduced interpreted execution capabilities, representing a significant enhancement. Following Cowlishaw’s departure from IBM in 2010, IBM transferred the NetRexx source code to RexxLA in June 2011 to support ongoing open-source development.
Under RexxLA’s management, NetRexx 3.00 was released shortly thereafter, with subsequent updates including version 4.01 in March 2021, which incorporated support for the Java Platform Module System to ensure compatibility with Java versions 9 and later.
Although distributed under the ICU license—a variant closely related to the Expat License—this license had not received Open Source Initiative approval as of 2018.
Syntax
NetRexx’s syntax and object-oriented design differ from Object REXX, another IBM-developed object-oriented REXX variant available as open source software. Its successor, ooREXX, shares certain syntactical constructs such as LOOP and DO OVER, which are not present in traditional REXX.
Programs are written in NetRexx itself and utilize REXX’s decimal arithmetic as defined by ANSI X3.274.