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src/main/java/com/google/common/base/FinalizableReference.java

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+/*
+ * Copyright (C) 2007 The Guava Authors
+ *
+ * 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.common.base;
+
+/**
+ * Implemented by references that have code to run after garbage collection of
+ * their referents.
+ *
+ * @see FinalizableReferenceQueue
+ * @author Bob Lee
+ * @since 2.0 (imported from Google Collections Library)
+ */
+public interface FinalizableReference {
+	/**
+	 * Invoked on a background thread after the referent has been garbage collected
+	 * unless security restrictions prevented starting a background thread, in which
+	 * case this method is invoked when new references are created.
+	 */
+	void finalizeReferent();
+}