possible to force a 64-bit JVM to use 32-bit mode via the argument "-d32"?

Question

so I have some 3rd party native library that works only in 32 bit JVM across windows,osx,linux and I need to always enforce the java application to run in 32 bit JVM mode.

What about if the target system only has 64-bit JVM installed, would it be possible to force it to run the java application in 32 bit mode?

Answer 1

No.

The preconditions that you specified prohibit (okay, I'm precluding the bundle-the-JVM solution and install-the-JVM solution) the application from running in a 32-bit JRE. If you want to run your application in a 32-bit JVM, and your third party native library is only available as a 32-bit DLL, then you must use a 32-bit JVM. A 64-bit JVM cannot load the 32-bit library; there is no 32-bit mode to load such libraries.

Solutions include:

• Require the 32-bit JVM to be installed
• Bundle the 32-bit JVM (the three OS's - that'll be a pretty big burden)
• Install the 32-bit JVM for the user
• Use a different third party library / roll your own / find a 64-bit version of the third party library

Answer 2

With Java 6, no. With Java 7+, yes.

Use -d32 with Java 7

Answer 3

possible to force a 64-bit JVM to use 32-bit mode via the argument “-d32”?

As there is no such argument to the java command, the answer is obviously 'no'.