问FreeTTS找不到任何声音

EN

import com.sun.speech.freetts.Voice;
import com.sun.speech.freetts.VoiceManager;

public class FreeTTSVoice {

public static final String VOICE_ALAN = "alan";
public static final String VOICE_KEVIN = "kevin";
public static final String VOICE_KEVIN16 = "kevin16";

private Voice voice;

public FreeTTSVoice(String voiceName) {

    VoiceManager voiceManager = VoiceManager.getInstance();
    voice = voiceManager.getVoice(voiceName);

    if (voice == null) {
        System.err.println(
            "Cannot find a voice named "
            + voiceName + ".  Please specify a different voice.");
        System.exit(1);
    }
}

public void speak(String msg) {
    voice.speak(msg);

}

public void open() {
    voice.allocate();
}

public void close() {
    voice.deallocate();
}

public static void main(String[] args) {
    System.setProperty("freetts.voices", "com.sun.speech.freetts.en.us.cmu_us_kal.KevinVoiceDirectory");

    FreeTTSVoice me = new FreeTTSVoice(FreeTTSVoice.VOICE_KEVIN);
    me.open();
    me.speak("Hello java is smart. isn't is?");
    me.close();
}

    pkswatch@neurals:~/dev/java/speech/viame-speech$ javac FreeTTSVoice.java
    pkswatch@neurals:~/dev/java/speech/viame-speech$ java FreeTTSVoice 
    Exception in thread "main" java.lang.Error: Unable to load voice directory.java.lang.ClassNotFoundException: com.sun.speech.freetts.en.us.cmu_us_kal.KevinVoiceDirectory
    at com.sun.speech.freetts.VoiceManager.getVoiceDirectories(VoiceManager.java:198)
    at com.sun.speech.freetts.VoiceManager.getVoices(VoiceManager.java:110)
    at com.sun.speech.freetts.VoiceManager.getVoice(VoiceManager.java:502)
    at FreeTTSVoice.<init>(FreeTTSVoice.java:15)
    at FreeTTSVoice.main(FreeTTSVoice.java:39)