Java Native Access (JNA) really simple begginer question

[carek]

And the question is what do I do wrong? Here are my codes:

package jna;

import com.sun.jna.Library;
import com.sun.jna.Native;

public interface FFT extends Library {
	
	FFT INSTANCE = (FFT)
    Native.loadLibrary("SignalsImpl", FFT.class);

	public int nextpwr2(int size);
}

package jna;

import org.junit.Test;

public class SignalTest {
	
	@Test
	public void ShouldMakeASignalAndLoadNativeLibrary() {
		FFT.INSTANCE.nextpwr2(10);
	}
}

Exception:

java.lang.UnsatisfiedLinkError: Error looking up function 'nextpwr2': The specified procedure could not be found.

	at com.sun.jna.Function.<init>(Function.java:179)
	at com.sun.jna.NativeLibrary.getFunction(NativeLibrary.java:345)
	at com.sun.jna.NativeLibrary.getFunction(NativeLibrary.java:325)
	at com.sun.jna.Library$Handler.invoke(Library.java:203)
	at $Proxy4.nextpwr2(Unknown Source)
	at jna.SignalTest.ShouldMakeASignalAndLoadNativeLibrary(SignalTest.java:11)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
	at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
	at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:44)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:180)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:41)
	at org.junit.runners.ParentRunner$1.evaluate(ParentRunner.java:173)
	at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
	at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:220)
	at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:46)
	at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

I've got SignalsImpl.dll in my project directory... why it doesn't work? :( pls help, thx in advance

[toadaly]

You have not identified 'nextpwr2' to be native.

[carek]

actually the problem was that my boss gave me wrong dll :/