Well, the problem clearly is Java can't find class MorseCodeDecoder that you should have implemented in your solution like this:

public class MorseCodeDecoder {
    public static String decode(String morseCode) {
        // your brilliant code here, remember that you can access the preloaded Morse code table through MorseCode.get(code)
    }
}

Hi Jolaf

Im trying to run my code on CodeWars

Are you trying to run your tests here on CodeWars, or on your computer?

Hi

Could you please explain why the test case isn't working for Java.

assertThat(MorseCodeDecoder.decode(".... . -.-- .--- ..- -.. ."), is("HEY JUDE"));
^
symbol: variable MorseCodeDecoder
location: class MorseCodeDecoderTest
1 error

java.lang.RuntimeException: /MorseCodeDecoderTest.java:8: error: cannot find symbol
assertThat(MorseCodeDecoder.decode(".... . -.-- .--- ..- -.. ."), is("HEY JUDE"));
^
symbol: variable MorseCodeDecoder
location: class MorseCodeDecoderTest
1 error