docs: public static void combine(String saveFileName, String... files) throws Exception{
  		File mFile=new File(saveFileName); 
  
  		if(!mFile.exists()){ 
  			mFile.createNewFile(); 
  		} 
  		
  		FileOutputStream os = new FileOutputStream(mFile);
  		FileChannel mFileChannel = os.getChannel(); 
  		FileChannel inFileChannel; 
  		for(String file:files){
  			File f = new File(file);
  			if(!f.exists())
  				continue;
  			inFileChannel=new FileInputStream(f).getChannel(); 
  			inFileChannel.transferTo(0, inFileChannel.size(), mFileChannel); 
  
  			inFileChannel.close(); 
  		} 
  
  		mFileChannel.close(); 
  		os.close();
  	}