content: /*
   * Copyright (C) 2008 ZXing authors
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.google.zxing.decoding;
  
  import android.os.Handler;
  import android.os.Looper;
  
  import com.google.zxing.BarcodeFormat;
  import com.google.zxing.DecodeHintType;
  import com.google.zxing.ResultPointCallback;
  import com.google.zxing.activity.CaptureActivity;
  
  import java.util.Hashtable;
  import java.util.Vector;
  import java.util.concurrent.CountDownLatch;
  
  /**
   * This thread does all the heavy lifting of decoding the images.
   * �����߳�
   */
  final class DecodeThread extends Thread {
  
    public static final String BARCODE_BITMAP = "barcode_bitmap";
    private final CaptureActivity activity;
    private final Hashtable<DecodeHintType, Object> hints;
    private Handler handler;
    private final CountDownLatch handlerInitLatch;
  
    DecodeThread(CaptureActivity activity,
                 Vector<BarcodeFormat> decodeFormats,
                 String characterSet,
                 ResultPointCallback resultPointCallback) {
  
      this.activity = activity;
      handlerInitLatch = new CountDownLatch(1);
  
      hints = new Hashtable<DecodeHintType, Object>(3);
  
      if (decodeFormats == null || decodeFormats.isEmpty()) {
      	 decodeFormats = new Vector<BarcodeFormat>();
      	 decodeFormats.addAll(DecodeFormatManager.ONE_D_FORMATS);
      	 decodeFormats.addAll(DecodeFormatManager.QR_CODE_FORMATS);
      	 decodeFormats.addAll(DecodeFormatManager.DATA_MATRIX_FORMATS);
      }
      
      hints.put(DecodeHintType.POSSIBLE_FORMATS, decodeFormats);
  
      if (characterSet != null) {
        hints.put(DecodeHintType.CHARACTER_SET, characterSet);
      }
  
      hints.put(DecodeHintType.NEED_RESULT_POINT_CALLBACK, resultPointCallback);
    }
  
    Handler getHandler() {
      try {
        handlerInitLatch.await();
      } catch (InterruptedException ie) {
        // continue?
      }
      return handler;
    }
  
    @Override
    public void run() {
      Looper.prepare();
      handler = new DecodeHandler(activity, hints);
      handlerInitLatch.countDown();
      Looper.loop();
    }
  
  }
  