private boolean createFileChannel(){
		File requestedFile = new File(this.filePath);
		if(requestedFile != null && requestedFile.exists()){
		    try {				    	
		    	// 直接通过文件管道将文件内容输出到客户端
				this.fileInput = new FileInputStream(requestedFile);   
				this.fileChannel = fileInput.getChannel(); 
		    } catch (IOException e) {   
		      e.printStackTrace(); 
		      this.closeChannel();
		    }
		    return true;
		}
		
		return false;
	}