Using a library (jcurses) that uses jni

Question

I'm having trouble uses the JCurses library. Here's what's happening:
ls -Ajcurses.jar  .keepme  libjcurses.so  Test.java
javac Test.java -classpath jcurses.jar
ls -Ajcurses.jar  .keepme  libjcurses.so  Test.class  Test.java
java Test -classpath jcurses.jarException in thread "main" java.lang.NoClassDefFoundError: jcurses/system/Toolkit
        at Test.main(Test.java:6)
rm Test.class
jar xvf jcurses.jar jcurses/...(no jar error outputs)...
ls -Ajcurses/ jcurses.jar  .keepme  libjcurses.so  Test.java
javac Test.java
ls -Ajcurses/ jcurses.jar  .keepme  libjcurses.so  Test.class  Test.java
java TestException in thread "main" java.lang.ExceptionInInitializerError
        at Test.main(Test.java:6)
Caused by: java.lang.NullPointerException
        at jcurses.system.Toolkit.getLibraryPath(Toolkit.java:111)
        at jcurses.system.Toolkit.<clinit>(Toolkit.java:37)
        ... 1 moreWhy does running "java Test" the first time output something different than the second just because? Also, why isn't the second working?

Answer 1

Ok I got it working now. I used
>java -cp .:jcurses.jar TestThe part that was really confusing me was:
>java -cp jcurses.jar Test
Exception in thread "main" java.lang.NoClassDefFoundError: TestI forgot that the java command only includes the current directory in the classpath if none is specified. Thats why >java Test worked: it used the default classpath which consists of the current directory, and the class I was executing and the library I was using were both in the current directory, so java located them, but the library failed because its classes assume that they will be executed from a jar. The reason >java -cp jcurses.jar Test didn't work is because the current directory was no longer part of the classpath, so java couldn't find the Test class which was in the current directory.
Thanks.