architectury-loom/src/main/java/net/fabricmc/loom/util/LazyCloseable.java

/*
 * This file is part of fabric-loom, licensed under the MIT License (MIT).
 *
 * Copyright (c) 2023 FabricMC
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package net.fabricmc.loom.util;

import java.io.Closeable;
import java.io.IOException;
import java.util.function.Consumer;
import java.util.function.Supplier;

// Not thread safe
public class LazyCloseable<T> implements Closeable {
	private final Supplier<T> valueSupplier;
	private final Consumer<T> closeConsumer;
	private T value;

	public LazyCloseable(Supplier<T> valueSupplier, Consumer<T> closeConsumer) {
		this.valueSupplier = valueSupplier;
		this.closeConsumer = closeConsumer;
	}

	public T get() {
		if (value == null) {
			value = valueSupplier.get();
		}

		return value;
	}

	@Override
	public void close() throws IOException {
		if (value != null) {
			closeConsumer.accept(value);
			value = null;
		}
	}
}