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javadlljava-native-interface

load dll error while using System.loadLibrary()

I'm making a program use JNI to call some native directives. My code is:System.loadLibrary("poc_NativeShellExecutor");

When I run the code, I got the exception:

Caused by: java.lang.UnsatisfiedLinkError: no poc_NativeShellExecutor in java.library.path at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1860) at java.lang.Runtime.loadLibrary0(Runtime.java:845) at java.lang.System.loadLibrary(System.java:1084)

I check the java.library.path and I'm sure I do put the poc_NativeShellExecutor.dll in C:\Windows\System32. Here is some info of my system:

Java version: 1.7.0_03, vendor: Oracle Corporation
Java home: E:\Program Files (x86)\Java\jdk1.7.0_03\jre
Default locale: en_US, platform encoding: GBK
OS name: "windows 7", version: "6.1", arch: "x86", family: "windows"

Could u please give me some help?

Solution

  • This is not the solution, but additional data, that I hope can help to find one.

    I have the same issue as the OP.

    My system is Windows7 Ultimate x64 SP1.
    I run my 32-bit test_x86.dll using the 32-bit jvm 1.6.0_29.

    I've tried to place test_x86.dll in the following folders:

    C:\
C:\Windows
C:\Program Files (x86)

    and it works: my test_x86.dll is successfully loaded.

    But if I place my dll into

    C:\Windows\System32

    I get the exception:

    Exception in thread "main" java.lang.UnsatisfiedLinkError: no test_x86 in java.library.path

    I change my java.library.path each time before trying to load the dll, so it always starts with the corresponding directory:

    java.library.path = C:/;C:\Program Files (x86)\Java\jre6\bin; ...
java.library.path = C:/Windows;C:\Program Files (x86)\Java\jre6\bin; ...
java.library.path = C:/Program Files (x86);C:\Program Files (x86)\Java\jre6\bin; ...
java.library.path = C:/Windows/System32;C:\Program Files (x86)\Java\jre6\bin; ...

    I also tried to use the default java.library.path (that contains C:\Windows\System32 by default) with test_x86.dll in C:\Windows\System32. No luck: it also leads to the exception above.

    I always have the single copy of test_x86.dll in folders that are in the java.library.path, i.e. only one of the folders contain that file at a time.

    Conclusion:

    It seems that in Windows 7 x64 the C:/Windows/System32 have some tricky restrictions.

    Earlier on my Windows XP 32-bit machine, I never warried about C:\Windows\System32 folder and java.library.path changes. I've simply used the System.loadLibrary("test_x86"); call with test_x86.dll in that folder, and it always worked.