| /* |
| * Copyright 2014 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.hardware.camera2.cts.helpers; |
| |
| import java.io.Closeable; |
| import java.io.IOException; |
| |
| /** |
| * Helper set of methods for dealing with objects that are sometimes {@code null}. |
| * |
| * <p>Used to remove common patterns like: <pre>{@code |
| * if (obj != null) { |
| * obj.doSomething(); |
| * }</pre> |
| * |
| * If this is common, consider adding {@code doSomething} to this class so that the code |
| * looks more like <pre>{@code |
| * MaybeNull.doSomething(obj); |
| * }</pre> |
| */ |
| public class MaybeNull { |
| /** |
| * Close the underlying {@link AutoCloseable}, if it's not {@code null}. |
| * |
| * @param closeable An object which implements {@link AutoCloseable}. |
| * @throws Exception If {@link AutoCloseable#close} fails. |
| */ |
| public static <T extends AutoCloseable> void close(T closeable) throws Exception { |
| if (closeable != null) { |
| closeable.close(); |
| } |
| } |
| |
| /** |
| * Close the underlying {@link UncheckedCloseable}, if it's not {@code null}. |
| * |
| * <p>No checked exceptions are thrown. An unknown runtime exception might still |
| * be raised.</p> |
| * |
| * @param closeable An object which implements {@link UncheckedCloseable}. |
| */ |
| public static <T extends UncheckedCloseable> void close(T closeable) { |
| if (closeable != null) { |
| closeable.close(); |
| } |
| } |
| |
| /** |
| * Close the underlying {@link Closeable}, if it's not {@code null}. |
| * |
| * @param closeable An object which implements {@link Closeable}. |
| * @throws Exception If {@link Closeable#close} fails. |
| */ |
| public static <T extends Closeable> void close(T closeable) throws IOException { |
| if (closeable != null) { |
| closeable.close(); |
| } |
| } |
| |
| // Suppress default constructor for noninstantiability |
| private MaybeNull() { throw new AssertionError(); } |
| } |