ThreadModule.java

import android.support.annotation.Nullable;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import java.lang.ref.WeakReference;

public abstract class ThreadModule {
    private Handler mHandler;
    private boolean mInitialized = false;

    public void initialize() {
        new Thread(new ThreadModuleRunner(this)).start();
    }

    @Nullable
    public Handler isReadyThread() {
        return getHandler();
    }

    public boolean finish() {
        Handler handler = getHandler();
        if (handler != null) {
            handler.getLooper().quit();
            return true;
        } else {
            return false;
        }
    }

    public boolean sendMessage(Message msg) {
        return mHandler.sendMessage(msg);
    }

    public abstract void handleMessage(Message msg);

    private synchronized Handler getHandler() {
        return mInitialized ? mHandler : null;
    }

    private synchronized void setInitialized(Handler handler) {
        mInitialized = true;
        mHandler = handler;
    }

    private static class ThreadModuleRunner implements Runnable {
        private final WeakReference<ThreadModule> moduleRef;
        public ThreadModuleRunner(ThreadModule module) {
            moduleRef = new WeakReference<>(module);
        }

        @Override
        public void run() {
            Looper.prepare();
            if (initializeModule()) Looper.loop();
            /* Thread end */
        }

        private boolean initializeModule() {
            ThreadModule module = moduleRef.get();
            if (module != null) {
                Handler handler = new ThreadModuleHandler(module);
                module.setInitialized(handler);
                return true;
            } else {
                return false;
            }
        }
    }

    private static class ThreadModuleHandler extends Handler {
        private final WeakReference<ThreadModule> moduleRef;
        public ThreadModuleHandler(ThreadModule module) {
            super();
            moduleRef = new WeakReference<>(module);
        }

        @Override
        public void handleMessage(Message msg) {
            ThreadModule module = moduleRef.get();
            if (module == null) {
                getLooper().quit();
            } else {
                module.handleMessage(msg);
            }
        }
    }
}