Windows command line processing

Kumar Srinivasan kumar.x.srinivasan at
Thu May 23 14:40:59 UTC 2013

Hello Thomas,

There are long standing bugs in this area, it all depends what arguments 
are being
passed with  Unicode code pages. This is somewhat a convoluted, as the 
JNI invocation
APIs are not Unicode friendly. Also we have a common code base for 
shared launcher
logic between the *nixes and Windows.

However as you pointed,  we can pass UTF8 parameters such as main class, and
application arguments to JVM as UTF-8.

We already have tests to exercises these conditions, please see 
however on Windows the Regional Settings must be set correctly for the 


> I've observed issues with passing non-ASCII characters through the command  line to a Java program on Windows.  It seems that even though I can invoke java.exe through CreateProcess, passing a full range of Unicode characters, and even though the Java main accepts strings of Unicode characters, the launcher's C main function converts the Unicode to the local ANSI code page.  Thus any characters not in the local code page are lost.  This seems like a bug to me.
> As a proof of concept, I changed jdk/src/share/bin/main.c to call GetCommanLineW instead of GetCommandLine, and then converted that string to UTF-8.  For my test, I set sun.jnu.encoding to UTF-8 so that makePlatformString in LauncherHelper would just work.
> -------------------------------------
> Tom Salter  |  Software Engineer  |  Java & Middleware Development
> Unisys  |  2476 Swedesford Road  |  Malvern, PA  19355   |  610-648-2568 |  N385-2568

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