JNA java.lang.UnsatisfiedLinkError和找不到指定的模块

Question

I'm putting together a jar that will let me call commands only available to natives (the jar uses natives rather then the actual program). Now I ran into a problem, whenever I load the DLL. Here is the error:

Exception in thread "main" java.lang.UnsatisfiedLinkError: Unable to load library 'myDLL.dll': The specified module could not be found.

at com.sun.jna.NativeLibrary.loadLibrary(NativeLibrary.java:194)
at com.sun.jna.NativeLibrary.getInstance(NativeLibrary.java:283)
at com.sun.jna.Library$Handler.<init>(Library.java:142)
at com.sun.jna.Native.loadLibrary(Native.java:368)
at com.sun.jna.Native.loadLibrary(Native.java:353)
at src.NativeBridgeJar.<clinit>(NativeBridgeJar.java:6)
at src.Main.main(Main.java:6)

I don't why what the cause of this error would be. I made sure I set the native library path to the folder with the native. Does anyone have an idea? Thanks in advanced!

Answer 1

A) when you call Native.loadLibrary() , you may provide a shorthand name ("myDll"), a filename ("myDll.dll"), or the absolute path of the shared library ("c:/users/me/myDll.dll").

B) If you don't provide an absolute path to the library, you may tell it where to load the DLL by specifying jna.library.path , or making it available on java.library.path (there are other options described in the NativeLibrary javadoc ).

Answer 2

You should show JVM your dlls location. It can be done with -Djava.library.path=pathToDll VM argument

Answer 3

I had the same problem until I put my .dll file into C:\\Windows\\System32 since it was a C++ DLL and had dependencies on Kernel32.dll and MSVCR100.dll in that folder. That seemed to work.

Answer 4

In addition to setting the path of dll using -Djava.library.path=pathToDll or System.setProperty("jna.library.path","pathToDll"); make sure the specific Visual C++ xxxx Redistributable Package is installed in your Windows(bcs the windows native libraries should have been built with specific VisualStudio xxxx)