Cherry pick branch 'genexuslabs:gamutils_eo' into beta

Author: sgrampone

gamutils/src/main/java/com/genexus/gam/GamUtilsEO.java

@@ -43,6 +43,8 @@ public static String randomHexaBits(int bits) {
 		return Random.hexaBits(bits);
 	}
 
+	public static String randomUrlSafeCharacters(int length) { return Random.urlSafe(length); }
+
 	//**JWK**//
 
 	public static String generateKeyPair() {

gamutils/src/main/java/com/genexus/gam/utils/Random.java

@@ -32,6 +32,19 @@ public static String alphanumeric(int length) {
 		return sb.toString();
 	}
 
+	public static String urlSafe(int length) {
+		SecureRandom random = instanceRandom();
+		if (random == null) {
+			logger.error("randomurlSafeCharacters SecureRandom is null");
+			return "";
+		}
+		String characters = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-_.~";
+		StringBuilder sb = new StringBuilder(length);
+		for (int i = 0; i < length; i++)
+			sb.append(characters.charAt(random.nextInt(characters.length())));
+		return sb.toString();
+	}
+
 	public static String numeric(int length) {
 		SecureRandom random = instanceRandom();
 		if (random == null) {

gamutils/src/test/java/com/genexus/gam/utils/test/RandomTest.java

@@ -56,6 +56,21 @@ public void testRandomAlphanumeric() {
 		Assert.assertEquals("l256 alphanumeric: ", l256, l256_string.length());
 	}
 
+	@Test
+	public void testRandomUrlSafeCharacters() {
+		String l5_string = GamUtilsEO.randomUrlSafeCharacters(l5);
+		Assert.assertEquals("l5 urlSafeCharacters: ", l5, l5_string.length());
+
+		String l10_string = GamUtilsEO.randomUrlSafeCharacters(l10);
+		Assert.assertEquals("l10 urlSafeCharacters: ", l10, l10_string.length());
+
+		String l128_string = GamUtilsEO.randomUrlSafeCharacters(l128);
+		Assert.assertEquals("l128 urlSafeCharacters: ", l128, l128_string.length());
+
+		String l256_string = GamUtilsEO.randomUrlSafeCharacters(l256);
+		Assert.assertEquals("l256 urlSafeCharacters: ", l256, l256_string.length());
+	}
+
 	@Test
 	public void testHexaBits() {
 		int[] lengths = new int[]{32, 64, 128, 256, 512, 1024};