Github user jwagenleitner commented on a diff in the pull request:
https://github.com/apache/groovy/pull/489#discussion_r100162813
--- Diff:
src/main/org/codehaus/groovy/util/ManagedConcurrentLinkedQueue.java ---
@@ -0,0 +1,187 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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 org.codehaus.groovy.util;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.List;
+import java.util.NoSuchElementException;
+import java.util.concurrent.ConcurrentLinkedQueue;
+
+/**
+ * A queue that stores the values wrapped in a Reference, the type of
which is
+ * determined by the provided {@link ReferenceBundle}. Values stored in
this queue
+ * that are put on the {@code ReferenceQueue} will be removed from the
list when
+ * reference processing for the {@code ReferenceQueue} is done.
+ *
+ * This queue is backed by a {@link ConcurrentLinkedQueue} and is thread
safe. The
+ * iterator will only return non-null values (reachable) and is based on
the
+ * "weakly consistent" iterator of the underlying {@link
ConcurrentLinkedQueue}.
+ *
+ * @param <T> the type of values to store
+ */
+public class ManagedConcurrentLinkedQueue<T> implements Iterable<T> {
+
+ private final ReferenceBundle bundle;
+ private final ConcurrentLinkedQueue<Element<T>> queue;
+
+ /**
+ * Creates an empty ManagedConcurrentLinkedQueue that will use the
given
+ * {@code ReferenceBundle} to store values as the given Reference
+ * type.
+ *
+ * @param bundle used to create the appropriate Reference type
+ * for the values stored
+ */
+ public ManagedConcurrentLinkedQueue(ReferenceBundle bundle) {
+ this.bundle = bundle;
+ this.queue = new ConcurrentLinkedQueue<Element<T>>();
+ }
+
+ /**
+ * Adds the specified value to the queue.
+ *
+ * @param value the value to add
+ */
+ public void add(T value) {
+ Element<T> e = new Element<T>(value);
+ queue.offer(e);
+ }
+
+ /**
+ * Returns {@code true} if this queue contains no elements.
+ * <p>
+ * This method does not check the elements to verify they contain
+ * non-null reference values.
+ */
+ public boolean isEmpty() {
+ return queue.isEmpty();
+ }
+
+ /**
+ * Returns an array containing all values from this queue in the
sequence they
+ * were added.
+ *
+ * @param tArray the array to populate if big enough, else a new array
with
+ * the same runtime type
+ * @return an array containing all non-null values in this queue
+ */
+ public T[] toArray(T[] tArray) {
+ return values().toArray(tArray);
+ }
+
+ /**
+ * Returns an unmodifiable list containing all values from this queue
in the
+ * sequence they were added.
+ */
+ public List<T> values() {
+ Iterator<T> itr = iterator();
+ if (!itr.hasNext()) {
+ return Collections.emptyList();
+ }
+ List<T> result = new ArrayList<T>(100);
+ result.add(itr.next());
+ while (itr.hasNext()) {
+ result.add(itr.next());
+ }
+ return Collections.unmodifiableList(result);
+ }
+
+ /**
+ * Returns an iterator over all non-null values in this queue. The
values should be
+ * returned in the order they were added.
+ */
+ @Override
+ public Iterator<T> iterator() {
+ return new Iter(queue.iterator());
+ }
+
+ private final class Element<V> extends ManagedReference<V> {
+
+ Element(V value) {
+ super(bundle, value);
+ }
+
+ @Override
+ public void finalizeReference() {
+ queue.remove(this);
+ super.finalizeReference();
+ }
+
+ }
+
+ private final class Iter implements Iterator<T> {
--- End diff --
think this can be made a static nested class
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---
