/*
 * Copyright (C) 2024 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.graphics.pdf.utils;

/**
 * Utility class comprising of static methods to check correct constructor or method invocation.
 *
 * @hide
 */
public final class Preconditions {
    /**
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * @param reference    an object reference
     * @param errorMessage the exception message to use if the check fails
     * @return the non-null reference that was validated
     * @throws NullPointerException if {@code reference} is null
     */
    public static <T> T checkNotNull(T reference, String errorMessage) {
        if (reference == null) {
            throw new NullPointerException(errorMessage);
        }
        return reference;
    }

    /**
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * @param expression   a boolean expression
     * @param errorMessage the exception message to use if the check fails
     * @throws IllegalArgumentException if {@code expression} is false
     */
    public static void checkArgument(boolean expression, String errorMessage) {
        if (!expression) {
            throw new IllegalArgumentException(errorMessage);
        }
    }
}