51 lines
968 B
Java
51 lines
968 B
Java
// SPDX-FileCopyrightText: 2021 Paul Schaub <vanitasvitae@fsfe.org>
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//
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// SPDX-License-Identifier: Apache-2.0
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package sop.util;
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/**
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* Backport of java.util.Optional for older Android versions.
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*
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* @param <T> item type
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*/
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public class Optional<T> {
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private final T item;
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public Optional() {
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this(null);
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}
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public Optional(T item) {
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this.item = item;
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}
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public static <T> Optional<T> of(T item) {
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if (item == null) {
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throw new NullPointerException("Item cannot be null.");
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}
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return new Optional<>(item);
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}
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public static <T> Optional<T> ofNullable(T item) {
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return new Optional<>(item);
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}
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public static <T> Optional<T> ofEmpty() {
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return new Optional<>(null);
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}
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public T get() {
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return item;
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}
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public boolean isPresent() {
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return item != null;
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}
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public boolean isEmpty() {
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return item == null;
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}
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}
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