Regex for fake programming language

I have the task of creating a lexical analyzer that translates the language into a series of tokens. I use java.util.regex to go through a string that finds different tokens, and I put them in an array through which I will pass, and use this to assign my corresponding tokens to them. Here is part of my program:

public static void main(String args[]) throws FileNotFoundException, IOException{

        String[] symbols = {"+","-","*","/","<","<=",">",">=","==","!=","=",";",",",".","(",")","[","]","{","}","/*","*/","//"};
        String[] input;
        FileInputStream fstream = new FileInputStream("src\\testCode.txt");
        BufferedReader br = new BufferedReader(new InputStreamReader(fstream));
        StringBuilder sb = new StringBuilder();
        String s;
        String ret = "";
        while((s = br.readLine()) != null){
            sb.append(s);
        }

        ret = sb.toString();

        input = regexChecker("regex goes here",ret);

        for (int i = 0; i < input.length; i++) {
            System.out.println(input[i]);

        }
        System.out.println(input.length);
        in.close();       
    }  

public static String[] regexChecker(String theRegex, String str2Check){
         List<String> allMatches = new ArrayList<String>();
        Pattern checkRegex = Pattern.compile(theRegex);
        Matcher regexMatcher = checkRegex.matcher(str2Check);

        while(regexMatcher.find()){
            //regexInput = new String[regexMatcher.group().length()];
            allMatches.add(regexMatcher.group());
        }
        String[] regexInput = allMatches.toArray(new String[allMatches.size()]);

        return regexInput;
    }

: , ? , ? : , . . - . , int, double, if .. , *,/, + ..

, , , 1, .

(?://.*)|(/\\*(?:.|[\\n\\r])*?\\*/) , , , , . ?