JNI教程，无法加载库

Question

i am trying to do this tutorial it's for JNI

https://netbeans.org/kb/docs/cnd/beginning-jni-linux.html

i already did everything in there, but i am having this trouble

Exception in thread "main" java.lang.UnsatisfiedLinkError: Can't load library: /home/usr/NetBeansProjects/JNIDemoCdl/dist/libJNIDemoCdl.so
at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1846)
at java.lang.Runtime.load0(Runtime.java:795)
at java.lang.System.load(System.java:1061)
at jnidemojava.Main.<clinit>(Main.java:13)

Java Result: 1

i am kind of stuck with JNI for a time now, and i could use some help, thanks

Answer 1

Make sure you have read/write permissions recursively over the directory structure and the lib file itself.

Try

sudo chmod ug+rwX -R /home/usr/NetBeansProjects/

That will add read/write permissions to the files and dirs, and execute permissions on directories and files that already have the execute flag for a user.

Hope this helps.

Answer 2

I never use mac but using windows i have faced same problem when i start working with jni. With your problem it could be many things or one the created dll flag is not correct, make sure you have used correct command to create dll. i use the following command

gcc -Wall -D_JNI_IMPLEMENTATION_ -Wl,--kill-at -I"C:\Program Files\Java\jdk1.7.0\include" -I"C:\Program Files\Java\jdk1.7.0\include\win32" -shared -o Sample1.dll Sample1.cpp

for this i used mingw compiler.

• in windows dll file on mac this will so. i used the command System.loadlibrary("youLibraryNameWithoutExtensionAndPath") before this go to your project build path and expand jre and select native library then click brows and select folder where you put dll/so file and ok. now try to run your code. this will solve issue.

but if the dll/so file have dependent lib then you have to put all dll file in system32 folder (in windows)