question: private static String unwrap ( String expression ) { if ( expression . startsWith ( "((" ) ) { expression = expression . substring ( expression . indexOf ( ")" ) + 1 , expression . length ( ) - 1 ) ; if ( expression . endsWith ( "]" ) ) { expression = expression . substring ( 0 , expression . lastIndexOf ( "[" ) ) ; } else { expression = expression . substring ( 0 , expression . lastIndexOf ( "." ) ) ; } } return expression ; }
target:  Removes the outermost property from a nested getter expression