java - How to trim a string using regex? -

i have alphabet: {'faa','fa','af'} , have string: "faaf"

i have regex: "(faa|fa|af)*" helps me match string alphabet.

how make java trim string into: {fa,af}, correct way write string: "faaf" based on alphabet?

here code:

        string regex = "(faa|fa|af)*";         string str = "faaf";         boolean ismatch = pattern.matches(regex, str);         if(ismatch)         {           //trim string             while(str.length()!=0)             {                 pattern pattern = pattern.compile("^(faa|fa|af)(faa|fa|af)*$");                 matcher mc = pattern.matcher(str);                 if (mc.find())                 {                      string l =mc.group(1);                      alphabet.add(l);                      str = str.substring(l.length());                      system.out.println("\n"+ l);                  }             }         } 

thanks aaron helped me problem.