question: private static String replaceStars ( String init ) { StringBuilder builder = new StringBuilder ( ) ; char [ ] chars = init . toCharArray ( ) ; for ( int i = 0 ; i < chars . length ; i ++ ) { if ( chars [ i ] == '*' && i == 0 && chars . length > 1 && chars [ i + 1 ] == ' ' ) { builder . append ( "(?:.+ |)" ) ; i ++ ; } else if ( chars [ i ] == '*' && i < ( chars . length - 1 ) && i > 0 && chars [ i + 1 ] == ' ' && chars [ i - 1 ] == ' ' ) { builder . deleteCharAt ( builder . length ( ) - 1 ) ; builder . append ( "(?:.+|)" ) ; } else if ( chars [ i ] == '*' && i == ( chars . length - 1 ) && i > 0 && chars [ i - 1 ] == ' ' ) { builder . deleteCharAt ( builder . length ( ) - 1 ) ; builder . append ( "(?: .+|)" ) ; } else if ( chars [ i ] == '*' ) { builder . append ( "(?:.*)" ) ; } else { builder . append ( chars [ i ] ) ; } } return builder . toString ( ) ; }
target:  Replaces the * characters in the string by a proper regular expression