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Java Language Conversion Assistant 

Java Language Conversion Assistant is a tool that converts Visual J++ 6.0 projects and Java-language files to Visual C#. By converting these files to Visual C#, you can leverage your existing code base and take advantage of the benefits of the .NET Framework.

The new Visual C# project contains all the new Visual C# code that can be generated automatically from the existing Visual J++ or Java-language code. For more information, see Converting Visual J++ or Java-Language Projects to Visual C#.

You can use Java Language Conversion Assistant to convert Visual J++ or Java-language applications and applet projects. They are converted in the following way:

Before Conversion After Conversion


Windows Forms applications


Web user controls

JSP pages or servlets

Web applications

You can host converted Web user controls in a browser just as you would an applet. Hosted controls are declared in HTML pages with the OBJECT tag, instead of the APPLET tag. Use the classid attribute to identify the control by specifying the path to the control and the fully qualified name of the control, separated by the pound sign (#), as shown in the following example:

<OBJECT id="myControl" classid="http:ControlLibrary1.dll#ControlLibrary1.myControl" VIEWASTEXT></OBJECT>

For the control to be displayed properly, the .dll file containing the control must either be in the same virtual directory as the Web page that is displaying it or be installed in the global assembly cache.

Support Classes

To convert functionality in the original project that is not available in Visual C#, Java Language Conversion Assistant creates support classes (also called managers) that duplicate the original functionality. Support classes are sometimes substantially different architecturally from the classes they emulate. Although every effort is made to preserve the original architecture of your application in the converted project, the primary goal of these support classes is to duplicate the original functionality.

Conversion Report

There might be some code in your project that could not be converted automatically. After you run the Java Language Conversion Assistant wizard, you can view the conversion report that details all errors, warnings, and issues encountered during the conversion process. Unconverted code is noted in the code of the new project by comments labeled UPGRADE_TODO. You can view conversion comments on the task list. Each conversion comment contains a link to a Help topic about how to convert that code manually. For more information, see Manually Upgrading Unconverted Code.

Security noteSecurity Note

You should review any C# code converted from Java using the Java Language Conversion Assistant tool for security issues. Any insecure Java code is converted into insecure C# code. In addition, the tool does not migrate code for certain Java classes, including some related to security, for example, authentication. In these cases, the upgrade report notes what code has not been migrated. It is important to review the report and to provide mitigation for any security issues.

See Also