J Sharp
Visual J# (pronounced "jay-sharp") is an implementation of the J# programming language that was a transitional language for programmers of Java and Visual J++ languages, so they could use their existing knowledge and applications with the .NET Framework.[1][2] It was introduced in 2002 and discontinued in 2007, with support for the final release of the product continuing until October 2017.
Paradigm | Object-oriented, structured, imperative |
---|---|
Developer | Microsoft |
First appeared | 2002 |
Stable release | v2.0 Second Edition
/ 18 May 2007 |
Platform | .NET Framework |
Website | msdn2 |
Influenced by | |
Java and Visual J++ |
J# worked with Java bytecode as well as source so it could be used to transition applications that used third-party libraries even if their original source code was unavailable. It was developed by the Hyderabad-based Microsoft India Development Center at HITEC City in India.[3][4]
Fundamental differences between J# and Java
Java and J# use the same general syntax but there are non-Java conventions in J# to support the .NET environment. For example, to use .NET "properties" with a standard JavaBean class, it is necessary to prefix getter and setter methods with the Javadoc-like annotation:
/** @beanproperty */
…and change the corresponding private variable name to be different from the suffix of the getXxx/setXxx names.
J# does not compile Java-language source code to Java bytecode (.class files), and does not support Java applet development or the ability to host applets directly in a web browser, although it does provide a wrapper called Microsoft J# Browser Controls for hosting them as ActiveX objects. Finally, Java Native Interface (JNI) and raw native interface (RNI) are substituted with P/Invoke; J# does not support remote method invocation (RMI).
InfoWorld said: "J#'s interface to the .NET framework is solid, but not as seamless as C#. In particular, J# code cannot define new .NET attributes, events, value types, or delegates. J# can make use of these language constructs if they are defined in an assembly written in another language, but its inability to define new ones limits J#'s reach and interoperability compared to other .NET languages."[5]
Contrariwise, Microsoft documentation for Visual Studio 2005 details the definition of .NET delegates,[6] events,[7] and value types[8] directly in J#.
Future of J#
In January 2007, Microsoft announced:[9]
- That Microsoft would produce an updated version of Visual J# 2.0, including a 64-bit redistributable version, called J# 2.0 Second Edition to meet customer demand for 64-bit runtime support. Microsoft released Visual J# 2.0 Second Edition in May 2007.[10]
- Retirement of the J# language and Java Language Conversion Assistant from future versions of Visual Studio. The last version, shipping with Visual Studio 2005, was supported until 2015.
- Calling J# code from .NET 4.0 code would fail unless vjsnativ.dll was pre-loaded.[11]
A link to download Visual J# 2005 Express Edition is no longer available from Microsoft's website
Visual J# is out of mainstream support but "Visual J# 2.0 Redistributable Second Edition released in 2007, with support continuing through to 2017 (5 years mainstream and 5 years extended support) on EN-US locales."[12] Support for the Visual J# Version 2.0 Redistributable Package Second Edition was discontinued on October 10, 2017.[13]
See also
- IKVM.NET – a free implementation of Java for Mono and .NET Framework
References
- "Visual J# Home". msdn.microsoft.com. Retrieved 2017-03-24.
- "Java to .NET Framework Migration Workshop: Free Online Training". Archived from the original on 2008-04-23. Retrieved 2020-01-28.CS1 maint: BOT: original-url status unknown (link)
- S Prasanna, Microsoft's VJ#.Net is made in India, Express Computer, 29 July 2002 Archived 28 November 2013 at the Wayback Machine
- "The Hindu Business Line : Microsoft lines up big plans for Hyderabad centre". www.thehindubusinessline.com.
- Yager, Tom (21 November 2001). "Just don't call J# Java". InfoWorld. Retrieved 2020-07-20.
- "delegate (Visual J#)". Visual Studio 2005. MSDN Library. Archived from the original on 2011-12-19.
- "Definition and Use of Events". Visual Studio 2005. MSDN Library. Archived from the original on 2011-12-19.
- "User-Defined Value Types". Visual Studio 2005. MSDN Library. Archived from the original on 2011-12-20.
- Microsoft Developer Network, Visual J# Product Announcement, 10 January 2007
- "Visual J# 2.0 Second Edition Redistributable Download". Archived from the original on 2007-05-23. Retrieved 2010-04-27.CS1 maint: BOT: original-url status unknown (link)
- "Calling J# code from .NET 4.0 - Windward Wrocks". Retrieved 6 March 2017.
- "Visual J# Home". Retrieved 6 March 2017.
- "End of Support for Visual Studio 2008 – in One Year". Retrieved 2017-04-11.
External links
- Official website
- Visual J# Design Choices: A Conversation with Pratap Lakshman at the Wayback Machine (archived 2007-04-16)