Java Utililty Methods Random String

return String.valueOf(System.currentTimeMillis());

String randomString = "";
while (randomString.length() < size) {
    randomString += Long.toHexString(random.nextLong());
return randomString.substring(0, size);

char[] chars = new char[length];
for (int i = 0; i < length; i++) {
    chars[i] = createRandomChar();
return new String(chars);

StringBuffer buffer = new StringBuffer();
buffer.append(createRandomLetter(startWithCapital));
int size = randomSize(8);
for (int i = 1; i < size; ++i) {
    buffer.append(createRandomLetter(false));
return buffer.toString();

char[] temp = new char[] { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f',
        'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
        'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T',
        'U', 'V', 'W', 'X', 'Y', 'Z' };
int size = temp.length;
StringBuffer bu = new StringBuffer();
for (int i = 0; i < num; i++) {
    int r = (int) (Math.random() * size);
...

String s = "";
for (int i = 0; i < digits.intValue(); i++) {
    s = s + "0";
int multiplier = Integer.valueOf(1 + s).intValue();
int temp = (int) (Math.random() * multiplier);
s = String.valueOf(temp);
return s;
...

String pswd = "";
String key = NUMBERS + LETTERSUP + LETTERDOWN;
for (int i = 0; i < length; i++)
    pswd += (key.charAt((int) (Math.random() * key.length())));
return pswd;

return generateRandomCharacters(N, false);

final StringBuffer randomString = new StringBuffer();
for (int i = 0; i < 5; i++) {
    char c = 'A';
    c = (char) (c + (int) (Math.random() * 26));
    randomString.append(c);
return randomString.toString();

int dimension = r.nextInt(10);
String[] sentence = new String[dimension];
for (int j = 0; j < dimension; j++) {
    char c = (char) r.nextInt(10);
    sentence[j] = c + "-" + c + "-" + c;
return sentence;