Move access widener jar processor for new processor API. (#787)

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

@@ -0,0 +1,58 @@
+/*
+ * 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;
+		}
+	}
+}