question: public static ColumnSpec decode ( String encodedColumnSpec , LayoutMap layoutMap ) { checkNotBlank ( encodedColumnSpec , "The encoded column specification must not be null, empty or whitespace." ) ; checkNotNull ( layoutMap , "The LayoutMap must not be null." ) ; String trimmed = encodedColumnSpec . trim ( ) ; String lower = trimmed . toLowerCase ( Locale . ENGLISH ) ; return decodeExpanded ( layoutMap . expand ( lower , true ) ) ; }
target:  Parses the encoded column specifications and returns a ColumnSpec object that represents the string. Variables are expanded using the given LayoutMap.