CoderByte challenge Simple Symbols

coderbyte_simpleSymbols.java

import java.util.*; 
import java.io.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

class Main {  
  public static String SimpleSymbols(String str) { 
    Pattern regex = Pattern.compile("[a-zA-Z]");
        Matcher match = regex.matcher(str);
        while (match.find())
            if (match.start() == 0 || match.end() == str.length()) // check not bookends
                return "false";
            else if (str.charAt(match.start() - 1) != '+' || str.charAt(match.start() + 1) != '+') // check + either side
                return "false";
        return "true";
  } 
  
  public static void main (String[] args) {  
    // keep this function call here     
    Scanner s = new Scanner(System.in);
    System.out.print(SimpleSymbols(s.nextLine())); 
  }   
  
}