001/*
002 * Copyright 2021 Global Biodiversity Information Facility (GBIF)
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.gbif.utils;
017
018import javax.annotation.Nullable;
019
020public final class PreconditionUtils {
021
022  private PreconditionUtils() {
023  }
024
025  /**
026   * Ensures the truth of an expression involving the state of the calling instance, but not
027   * involving any parameters to the calling method.
028   * From Guava.
029   *
030   * @param expression a boolean expression
031   * @throws IllegalStateException if {@code expression} is false
032   */
033  public static void checkState(boolean expression) {
034    if (!expression) {
035      throw new IllegalStateException();
036    }
037  }
038
039  /**
040   * Ensures the truth of an expression involving the state of the calling instance, but not
041   * involving any parameters to the calling method.
042   * From Guava.
043   *
044   * @param expression a boolean expression
045   * @param errorMessage the exception message to use if the check fails; will be converted to a
046   *     string using {@link String#valueOf(Object)}
047   * @throws IllegalStateException if {@code expression} is false
048   */
049  public static void checkState(boolean expression, @Nullable Object errorMessage) {
050    if (!expression) {
051      throw new IllegalStateException(String.valueOf(errorMessage));
052    }
053  }
054
055  /**
056   * Ensures the truth of an expression involving one or more parameters to the calling method.
057   * From Guava.
058   *
059   * @param expression a boolean expression
060   * @throws IllegalArgumentException if {@code expression} is false
061   */
062  public static void checkArgument(boolean expression) {
063    if (!expression) {
064      throw new IllegalArgumentException();
065    }
066  }
067
068  /**
069   * Ensures the truth of an expression involving one or more parameters to the calling method.
070   * From Guava.
071   *
072   * @param expression a boolean expression
073   * @param errorMessage the exception message to use if the check fails; will be converted to a
074   *     string using {@link String#valueOf(Object)}
075   * @throws IllegalArgumentException if {@code expression} is false
076   */
077  public static void checkArgument(boolean expression, @Nullable Object errorMessage) {
078    if (!expression) {
079      throw new IllegalArgumentException(String.valueOf(errorMessage));
080    }
081  }
082}