Java tutorial
package ch.cyberduck.core; /* * Copyright (c) 2002-2016 iterate GmbH. All rights reserved. * https://cyberduck.io/ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ import org.apache.commons.text.CharacterPredicate; import org.apache.commons.text.RandomStringGenerator; public class AlphanumericRandomStringService implements RandomStringService { @Override public String random() { return new RandomStringGenerator.Builder().withinRange('0', 'z').filteredBy(new CharacterPredicate() { @Override public boolean test(final int codePoint) { return Character.isAlphabetic(codePoint) || Character.isDigit(codePoint); } }).build().generate(8); } }