TextToSpeechAction.java

package edu.stanford.hci.r3.actions.types;

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;

import edu.stanford.hci.r3.actions.R3Action;

public class TextToSpeechAction implements R3Action {

        private static final String DEFAULT_FREETTS_VOICE = "kevin16";

        private static TextToSpeechAction instance;

        public static TextToSpeechAction getInstance() {
                if (instance == null) {
                        instance = new TextToSpeechAction();
                        instance.initialize();
                }
                return instance;
        }

        private boolean initialized;

        private String savedText;

        private Synthesizer synthesizer;

        private String voiceName = DEFAULT_FREETTS_VOICE;

        public TextToSpeechAction() {
                this("");
        }

        public TextToSpeechAction(String wordsToSay) {
                savedText = wordsToSay;
                // leave everything else null until it is invoked!
        }

        public void close() {
                try {
                        synthesizer.deallocate();
                } catch (EngineException e) {
                        e.printStackTrace();
                } catch (EngineStateError e) {
                        e.printStackTrace();
                }
                initialized = false;
        }

        public void initialize() {
                if (initialized) {
                        return; // already initialized
                }

                initialized = true;
                try {
                        voiceName = DEFAULT_FREETTS_VOICE;
                        SynthesizerModeDesc desc = new SynthesizerModeDesc(null, // engine name
                                        "general", // mode name
                                        Locale.US, // locale
                                        null, // running
                                        null); // voice
                        synthesizer = Central.createSynthesizer(desc);

                        // Get the synthesizer ready to speak
                        synthesizer.allocate();
                        synthesizer.resume();

                        // Choose the voice.
                        desc = (SynthesizerModeDesc) synthesizer.getEngineModeDesc();
                        Voice[] voices = desc.getVoices();
                        Voice voice = null;
                        for (Voice v : voices) {
                                if (v.getName().equals(voiceName)) {
                                        voice = v;
                                        break;
                                }
                        }
                        if (voice == null) {
                                System.err.println("Synthesizer does not have a voice named " + voiceName
                                                + ". Choosing the first available voice.");
                                voice = voices[0];
                        }
                        synthesizer.getSynthesizerProperties().setVoice(voice);
                } catch (IllegalArgumentException e) {
                        e.printStackTrace();
                } catch (EngineException e) {
                        e.printStackTrace();
                } catch (AudioException e) {
                        e.printStackTrace();
                } catch (EngineStateError e) {
                        e.printStackTrace();
                } catch (PropertyVetoException e) {
                        e.printStackTrace();
                }
        }

        public void invoke() {
                initialize();
                speak();
                close();
        }

        public void speak() {
                speak(savedText);
        }

        public void speak(String wordsToSpeak) {
                // Tell the synthesizer to speak and wait for it to complete.
                try {
                        synthesizer.speakPlainText(wordsToSpeak, null);
                        synthesizer.waitEngineState(Synthesizer.QUEUE_EMPTY);
                } catch (IllegalArgumentException e) {
                        e.printStackTrace();
                } catch (InterruptedException e) {
                        e.printStackTrace();
                }
        }
}

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