001/*
002 * SonarQube
003 * Copyright (C) 2009-2017 SonarSource SA
004 * mailto:info AT sonarsource DOT com
005 *
006 * This program is free software; you can redistribute it and/or
007 * modify it under the terms of the GNU Lesser General Public
008 * License as published by the Free Software Foundation; either
009 * version 3 of the License, or (at your option) any later version.
010 *
011 * This program is distributed in the hope that it will be useful,
012 * but WITHOUT ANY WARRANTY; without even the implied warranty of
013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014 * Lesser General Public License for more details.
015 *
016 * You should have received a copy of the GNU Lesser General Public License
017 * along with this program; if not, write to the Free Software Foundation,
018 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
019 */
020package org.sonar.test;
021
022import java.lang.reflect.Constructor;
023import java.lang.reflect.Modifier;
024
025/**
026 * Utilities for unit tests
027 *
028 * @since 2.2
029 */
030public final class TestUtils {
031
032  private TestUtils() {
033  }
034
035  /**
036   * Asserts that all constructors are private, usually for helper classes with
037   * only static methods. If a constructor does not have any parameters, then
038   * it's instantiated.
039   */
040  public static boolean hasOnlyPrivateConstructors(Class clazz) {
041    boolean ok = true;
042    for (Constructor constructor : clazz.getDeclaredConstructors()) {
043      ok &= Modifier.isPrivate(constructor.getModifiers());
044      if (constructor.getParameterTypes().length == 0) {
045        constructor.setAccessible(true);
046        try {
047          constructor.newInstance();
048        } catch (Exception e) {
049          throw new IllegalStateException(String.format("Fail to instantiate %s", clazz), e);
050        }
051      }
052    }
053    return ok;
054  }
055}