How to define mbrola.base property while we are using the Java speech API?

import javax.speech.EngineList;
import javax.speech.EngineCreate;
import javax.speech.synthesis.SynthesizerModeDesc;
import javax.speech.synthesis.Synthesizer;
import com.sun.speech.freetts.jsapi.FreeTTSEngineCentral;
import java.util.Locale;

public class HelloWorld {
    public static void main(String args[]) {

        try {
            // create SynthesizerModeDesc that will match the FreeTTS Synthesizer
            SynthesizerModeDesc modeDesc = new SynthesizerModeDesc(
                    null, 
                    "general", /* use "time" or "general" */
                    Locale.US, 
                    Boolean.FALSE,
                    null);
            if(modeDesc == null)
                System.out.println("Error creating mode descriptor");

            FreeTTSEngineCentral central = new FreeTT开发者_开发技巧SEngineCentral();
            Synthesizer synthesizer = null;

            EngineList list = central.createEngineList(modeDesc);
            if (list.size() > 0) { 
                EngineCreate creator = (EngineCreate) list.get(0); 
                synthesizer = (Synthesizer) creator.createEngine(); 
            }

            if (synthesizer == null) {
                System.err.println("Cannot create synthesizer");
                System.exit(1);
            }
            //get ready to speak
            synthesizer.allocate();
            synthesizer.resume();

            // say hello world
            synthesizer.speakPlainText("Hello, world!", null);
            // wait until speaking is done and clean up
            synthesizer.waitEngineState(Synthesizer.QUEUE_EMPTY);
            synthesizer.deallocate();

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}  

It's showing me the thing like "System property "mbrola.base" is undefined. Will not use MBROLA voices." So what should I do? I am not able to Listen any thing.

Copy speech.properties file into "java.home" or "user.home"