docs: public DataStreamSource<String> readTextFile(String filePath, String charsetName) {
  		Preconditions.checkArgument(!StringUtils.isNullOrWhitespaceOnly(filePath), "The file path must not be null or blank.");
  
  		TextInputFormat format = new TextInputFormat(new Path(filePath));
  		format.setFilesFilter(FilePathFilter.createDefaultFilter());
  		TypeInformation<String> typeInfo = BasicTypeInfo.STRING_TYPE_INFO;
  		format.setCharsetName(charsetName);
  
  		return readFile(format, filePath, FileProcessingMode.PROCESS_ONCE, -1, typeInfo);
  	}