Java Utililty Methods Random String

char[] chars = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();
return getRandomString(length, chars);

String RandomCode = "";
char[] codeSequence = { '3', '4', '5', '6', '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', '0', '1', '2', '3', '4', '5', '6',
        '7', '8', '9' };
Random random = new Random();
StringBuffer randomCode = new StringBuffer();
for (int i = 0; i < length; i++) {
    String strRand = String.valueOf(codeSequence[random.nextInt(40)]);
...

String s = Long.toHexString(Double.doubleToLongBits(rnd.nextDouble()));
StringBuilder strBuilder = new StringBuilder();
for (int i = 0; i < s.length() && i < length; i++) {
    strBuilder.append(s.charAt(Math.abs(rnd.nextInt()) % s.length()));
return strBuilder.toString();

Random rand = new Random(System.currentTimeMillis());
StringBuilder sb = new StringBuilder();
if (charset == null) {
    return sb.toString();
for (int i = 0; i < length; i++) {
    int pos = rand.nextInt(charset.length());
    sb.append(charset.charAt(pos));
...

String newstring = new String();
Random rand = new Random();
int i;
final char[] chars = { '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 length;
if (minLength == maxLength) {
    length = minLength;
} else {
    length = RANDOM.nextInt(maxLength - minLength) + minLength;
char[] randomString = new char[length];
for (int x = 0; x < length; x++) {
...

return getRandomString(randomPasswordLength, RANDOM_PATTERN);

Random random = new Random();
StringBuffer sb = new StringBuffer(size);
for (int i = 0; i < size; i++) {
    sb.append(c[Math.abs(random.nextInt(CHART_LENGHT))]);
return sb.toString();

Random random = new Random();
StringBuffer sb = new StringBuffer(size);
for (int i = 0; i < size; i++) {
    sb.append(c[Math.abs(random.nextInt()) % c.length]);
return sb.toString();

StringBuilder builder = new StringBuilder(size);
for (int i = 0; i < size; i++) {
    char c = (char) (random.nextInt(126 - 33) + 33);
    builder.append(c);
return builder.toString();