001/*
002 * The contents of this file are subject to the terms of the Common Development and
003 * Distribution License (the License). You may not use this file except in compliance with the
004 * License.
005 *
006 * You can obtain a copy of the License at legal/CDDLv1.0.txt. See the License for the
007 * specific language governing permission and limitations under the License.
008 *
009 * When distributing Covered Software, include this CDDL Header Notice in each file and include
010 * the License file at legal/CDDLv1.0.txt. If applicable, add the following below the CDDL
011 * Header, with the fields enclosed by brackets [] replaced by your own identifying
012 * information: "Portions copyright [year] [name of copyright owner]".
013 *
014 * Copyright 2016 ForgeRock AS.
015 */
016
017package org.forgerock.api.util;
018
019import java.util.regex.Pattern;
020
021/**
022 * API Descriptor model-validation utilities.
023 */
024public final class ValidationUtil {
025
026    private static final Pattern FIND_WHITESPACE_PATTERN = Pattern.compile("\\s");
027
028    private ValidationUtil() {
029        // empty
030    }
031
032    /**
033     * Checks a {@code String} for whitespace.
034     *
035     * @param s {@code String} to validate
036     * @return {@code true} if contains whitespace and {@code false} otherwise
037     */
038    public static boolean containsWhitespace(final String s) {
039        return FIND_WHITESPACE_PATTERN.matcher(s).find();
040    }
041
042    /**
043     * Determines if a {@code String} is {@code null}, or empty, or only contains whitespace.
044     *
045     * @param s {@code String} to validate
046     * @return {@code true} if {@code null} or empty, or only contains whitespace, and {@code false} otherwise
047     */
048    public static boolean isEmpty(final String s) {
049        return s == null || s.trim().isEmpty();
050    }
051
052    /**
053     * Determines if an array is {@code null} or zero-length.
054     *
055     * @param a Array to validate
056     * @return {@code true} if {@code null} or empty, and {@code false} otherwise
057     */
058    public static boolean isEmpty(final Object[] a) {
059        return a == null || a.length == 0;
060    }
061
062    /**
063     * Checks that there is only a single single non-{@code null} argument.
064     *
065     * @param args Arguments
066     * @return {@code true} if there is a single non-{@code null} argument, and {@code false} otherwise
067     */
068    public static boolean isSingleNonNull(final Object... args) {
069        boolean found = false;
070        if (args != null) {
071            for (final Object o : args) {
072                if (o != null) {
073                    if (found) {
074                        // there is more than one non-null argument
075                        return false;
076                    }
077                    found = true;
078                }
079            }
080        }
081        return found;
082    }
083
084    /**
085     * Returns false if the given Boolean parameter is {@code null}.
086     *
087     * @param boolVal boolean parameter to check
088     * @return {@code false} if the parameter is null, and the parameter itself otherwise
089     */
090    public static boolean nullToFalse(Boolean boolVal) {
091        return (boolVal == null) ? false : boolVal;
092    }
093}