code: @Override
  	public void configure(Configuration parameters) {
  		super.configure(parameters);
  		
  		// get the charset for the decoding
  		String charsetName = parameters.getString(CHARSET_NAME, DEFAULT_CHARSET_NAME);
  		if (charsetName == null || !Charset.isSupported(charsetName)) {
  			throw new RuntimeException("Unsupported charset: " + charsetName);
  		}
  		
  		if (charsetName.equals("ISO-8859-1") || charsetName.equalsIgnoreCase("ASCII")) {
  			this.ascii = true;
  		} else {
  			this.decoder = Charset.forName(charsetName).newDecoder();
  			this.byteWrapper = ByteBuffer.allocate(1);
  		}
  		
  		// get the field position to write in the record
  		this.pos = parameters.getInteger(FIELD_POS, 0);
  		if (this.pos < 0) {
  			throw new RuntimeException("Illegal configuration value for the target position: " + this.pos);
  		}
  	}
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