How to convert bangla text to speech in java?

Question

I can convert English text to speech in java. source code:

 import java.beans.PropertyVetoException;
 import java.util.Locale;
 import javax.speech.AudioException;
 import javax.speech.Central;
 import javax.speech.EngineException;
 import javax.speech.EngineStateError;
 import javax.speech.synthesis.Synthesizer;
 import javax.speech.synthesis.SynthesizerModeDesc;
 import javax.speech.synthesis.Voice;

 public class Speech {

   SynthesizerModeDesc desc;
   Synthesizer synthesizer;
   Voice voice;


  public void test(String voiceName)
    throws EngineException, AudioException, EngineStateError,
          PropertyVetoException
  {
    if (desc == null) {

     System.setProperty("freetts.voices",
       "com.sun.speech.freetts.en.us.cmu_us_kal.KevinVoiceDirectory");

     desc = new SynthesizerModeDesc(Locale.ENGLISH);
    Central.registerEngineCentral
    ("com.sun.speech.freetts.jsapi.FreeTTSEngineCentral");
  synthesizer = Central.createSynthesizer(desc);
  synthesizer.allocate();
  //synthesizer.resume();
 // SynthesizerModeDesc smd =
   desc = (SynthesizerModeDesc)synthesizer.getEngineModeDesc();
  Voice[] voices = desc.getVoices();
  Voice voice = null;
  for(int i = 0; i < voices.length; i++) {
    if(voices[i].getName().equals(voiceName)) {
      voice = voices[i];
      break;
    }
  }
  synthesizer.getSynthesizerProperties().setVoice(voice);
   }

  }



 public void doSpeak(String speakText)
throws EngineException, AudioException, IllegalArgumentException,
        InterruptedException
{
    synthesizer.speakPlainText(speakText,null);
   synthesizer.waitEngineState(Synthesizer.QUEUE_NOT_EMPTY);
}

But I can't understand how to convert Bangla text to speech in java. EX:
TEXT: "আমি একজন ছাএ ।"

Can anyone tell me how can I do this in java ?