| /* |
| * Copyright (C) 2016 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 com.google.android.exoplayer2.util; |
| |
| import android.os.Looper; |
| import android.text.TextUtils; |
| import androidx.annotation.Nullable; |
| import com.google.android.exoplayer2.ExoPlayerLibraryInfo; |
| import org.checkerframework.checker.nullness.qual.EnsuresNonNull; |
| import org.checkerframework.dataflow.qual.Pure; |
| |
| /** Provides methods for asserting the truth of expressions and properties. */ |
| public final class Assertions { |
| |
| private Assertions() {} |
| |
| /** |
| * Throws {@link IllegalArgumentException} if {@code expression} evaluates to false. |
| * |
| * @param expression The expression to evaluate. |
| * @throws IllegalArgumentException If {@code expression} is false. |
| */ |
| @Pure |
| public static void checkArgument(boolean expression) { |
| if (ExoPlayerLibraryInfo.ASSERTIONS_ENABLED && !expression) { |
| throw new IllegalArgumentException(); |
| } |
| } |
| |
| /** |
| * Throws {@link IllegalArgumentException} if {@code expression} evaluates to false. |
| * |
| * @param expression The expression to evaluate. |
| * @param errorMessage The exception message if an exception is thrown. The message is converted |
| * to a {@link String} using {@link String#valueOf(Object)}. |
| * @throws IllegalArgumentException If {@code expression} is false. |
| */ |
| @Pure |
| public static void checkArgument(boolean expression, Object errorMessage) { |
| if (ExoPlayerLibraryInfo.ASSERTIONS_ENABLED && !expression) { |
| throw new IllegalArgumentException(String.valueOf(errorMessage)); |
| } |
| } |
| |
| /** |
| * Throws {@link IndexOutOfBoundsException} if {@code index} falls outside the specified bounds. |
| * |
| * @param index The index to test. |
| * @param start The start of the allowed range (inclusive). |
| * @param limit The end of the allowed range (exclusive). |
| * @return The {@code index} that was validated. |
| * @throws IndexOutOfBoundsException If {@code index} falls outside the specified bounds. |
| */ |
| @Pure |
| public static int checkIndex(int index, int start, int limit) { |
| if (index < start || index >= limit) { |
| throw new IndexOutOfBoundsException(); |
| } |
| return index; |
| } |
| |
| /** |
| * Throws {@link IllegalStateException} if {@code expression} evaluates to false. |
| * |
| * @param expression The expression to evaluate. |
| * @throws IllegalStateException If {@code expression} is false. |
| */ |
| @Pure |
| public static void checkState(boolean expression) { |
| if (ExoPlayerLibraryInfo.ASSERTIONS_ENABLED && !expression) { |
| throw new IllegalStateException(); |
| } |
| } |
| |
| /** |
| * Throws {@link IllegalStateException} if {@code expression} evaluates to false. |
| * |
| * @param expression The expression to evaluate. |
| * @param errorMessage The exception message if an exception is thrown. The message is converted |
| * to a {@link String} using {@link String#valueOf(Object)}. |
| * @throws IllegalStateException If {@code expression} is false. |
| */ |
| @Pure |
| public static void checkState(boolean expression, Object errorMessage) { |
| if (ExoPlayerLibraryInfo.ASSERTIONS_ENABLED && !expression) { |
| throw new IllegalStateException(String.valueOf(errorMessage)); |
| } |
| } |
| |
| /** |
| * Throws {@link IllegalStateException} if {@code reference} is null. |
| * |
| * @param <T> The type of the reference. |
| * @param reference The reference. |
| * @return The non-null reference that was validated. |
| * @throws IllegalStateException If {@code reference} is null. |
| */ |
| @SuppressWarnings({"nullness:contracts.postcondition", "nullness:return"}) |
| @EnsuresNonNull({"#1"}) |
| @Pure |
| public static <T> T checkStateNotNull(@Nullable T reference) { |
| if (ExoPlayerLibraryInfo.ASSERTIONS_ENABLED && reference == null) { |
| throw new IllegalStateException(); |
| } |
| return reference; |
| } |
| |
| /** |
| * Throws {@link IllegalStateException} if {@code reference} is null. |
| * |
| * @param <T> The type of the reference. |
| * @param reference The reference. |
| * @param errorMessage The exception message to use if the check fails. The message is converted |
| * to a string using {@link String#valueOf(Object)}. |
| * @return The non-null reference that was validated. |
| * @throws IllegalStateException If {@code reference} is null. |
| */ |
| @SuppressWarnings({"nullness:contracts.postcondition", "nullness:return"}) |
| @EnsuresNonNull({"#1"}) |
| @Pure |
| public static <T> T checkStateNotNull(@Nullable T reference, Object errorMessage) { |
| if (ExoPlayerLibraryInfo.ASSERTIONS_ENABLED && reference == null) { |
| throw new IllegalStateException(String.valueOf(errorMessage)); |
| } |
| return reference; |
| } |
| |
| /** |
| * Throws {@link NullPointerException} if {@code reference} is null. |
| * |
| * @param <T> The type of the reference. |
| * @param reference The reference. |
| * @return The non-null reference that was validated. |
| * @throws NullPointerException If {@code reference} is null. |
| */ |
| @SuppressWarnings({"nullness:contracts.postcondition", "nullness:return"}) |
| @EnsuresNonNull({"#1"}) |
| @Pure |
| public static <T> T checkNotNull(@Nullable T reference) { |
| if (ExoPlayerLibraryInfo.ASSERTIONS_ENABLED && reference == null) { |
| throw new NullPointerException(); |
| } |
| return reference; |
| } |
| |
| /** |
| * Throws {@link NullPointerException} if {@code reference} is null. |
| * |
| * @param <T> The type of the reference. |
| * @param reference The reference. |
| * @param errorMessage The exception message to use if the check fails. The message is converted |
| * to a string using {@link String#valueOf(Object)}. |
| * @return The non-null reference that was validated. |
| * @throws NullPointerException If {@code reference} is null. |
| */ |
| @SuppressWarnings({"nullness:contracts.postcondition", "nullness:return"}) |
| @EnsuresNonNull({"#1"}) |
| @Pure |
| public static <T> T checkNotNull(@Nullable T reference, Object errorMessage) { |
| if (ExoPlayerLibraryInfo.ASSERTIONS_ENABLED && reference == null) { |
| throw new NullPointerException(String.valueOf(errorMessage)); |
| } |
| return reference; |
| } |
| |
| /** |
| * Throws {@link IllegalArgumentException} if {@code string} is null or zero length. |
| * |
| * @param string The string to check. |
| * @return The non-null, non-empty string that was validated. |
| * @throws IllegalArgumentException If {@code string} is null or 0-length. |
| */ |
| @SuppressWarnings({"nullness:contracts.postcondition", "nullness:return"}) |
| @EnsuresNonNull({"#1"}) |
| @Pure |
| public static String checkNotEmpty(@Nullable String string) { |
| if (ExoPlayerLibraryInfo.ASSERTIONS_ENABLED && TextUtils.isEmpty(string)) { |
| throw new IllegalArgumentException(); |
| } |
| return string; |
| } |
| |
| /** |
| * Throws {@link IllegalArgumentException} if {@code string} is null or zero length. |
| * |
| * @param string The string to check. |
| * @param errorMessage The exception message to use if the check fails. The message is converted |
| * to a string using {@link String#valueOf(Object)}. |
| * @return The non-null, non-empty string that was validated. |
| * @throws IllegalArgumentException If {@code string} is null or 0-length. |
| */ |
| @SuppressWarnings({"nullness:contracts.postcondition", "nullness:return"}) |
| @EnsuresNonNull({"#1"}) |
| @Pure |
| public static String checkNotEmpty(@Nullable String string, Object errorMessage) { |
| if (ExoPlayerLibraryInfo.ASSERTIONS_ENABLED && TextUtils.isEmpty(string)) { |
| throw new IllegalArgumentException(String.valueOf(errorMessage)); |
| } |
| return string; |
| } |
| |
| /** |
| * Throws {@link IllegalStateException} if the calling thread is not the application's main |
| * thread. |
| * |
| * @throws IllegalStateException If the calling thread is not the application's main thread. |
| */ |
| @Pure |
| public static void checkMainThread() { |
| if (ExoPlayerLibraryInfo.ASSERTIONS_ENABLED && Looper.myLooper() != Looper.getMainLooper()) { |
| throw new IllegalStateException("Not in applications main thread"); |
| } |
| } |
| } |