Further fixes #4405.

No review.

3 files changed, 24 insertions, 0 deletions

diff --git a/src/library/scala/collection/mutable/PriorityQueue.scala b/src/library/scala/collection/mutable/PriorityQueue.scala
index 1f7e4e7879..8eb72fada7 100644
--- a/src/library/scala/collection/mutable/PriorityQueue.scala
+++ b/src/library/scala/collection/mutable/PriorityQueue.scala
@@ -163,6 +163,14 @@ class PriorityQueue[A](implicit val ord: Ordering[A])
    *
    *  @return   the element with the highest priority.
    */
+  @deprecated("Use `head` instead.")
+  def max: A = if (resarr.p_size0 > 1) toA(resarr.p_array(1)) else throw new NoSuchElementException("queue is empty")
+
+  /** Returns the element with the highest priority in the queue,
+   *  or throws an error if there is no element contained in the queue.
+   *
+   *  @return   the element with the highest priority.
+   */
   override def head: A = if (resarr.p_size0 > 1) toA(resarr.p_array(1)) else throw new NoSuchElementException("queue is empty")
 
   /** Removes all elements from the queue. After this operation is completed,
diff --git a/src/library/scala/collection/mutable/PriorityQueueProxy.scala b/src/library/scala/collection/mutable/PriorityQueueProxy.scala
index f8330c3aac..912786359a 100644
--- a/src/library/scala/collection/mutable/PriorityQueueProxy.scala
+++ b/src/library/scala/collection/mutable/PriorityQueueProxy.scala
@@ -73,6 +73,14 @@ abstract class PriorityQueueProxy[A](implicit ord: Ordering[A]) extends Priority
    *
    *  @return   the element with the highest priority.
    */
+  override def head: A = self.head
+
+  /** Returns the element with the highest priority in the queue,
+   *  or throws an error if there is no element contained in the queue.
+   *
+   *  @return   the element with the highest priority.
+   */
+  @deprecated("Use `head` instead.")
   override def max: A = self.max
 
   /** Removes all elements from the queue. After this operation is completed,
diff --git a/src/library/scala/collection/mutable/SynchronizedPriorityQueue.scala b/src/library/scala/collection/mutable/SynchronizedPriorityQueue.scala
index 3295b43d7f..523f5154e0 100644
--- a/src/library/scala/collection/mutable/SynchronizedPriorityQueue.scala
+++ b/src/library/scala/collection/mutable/SynchronizedPriorityQueue.scala
@@ -71,6 +71,14 @@ class SynchronizedPriorityQueue[A](implicit ord: Ordering[A]) extends PriorityQu
    *
    *  @return   the element with the highest priority.
    */
+  override def head: A = synchronized { super.head }
+
+  /** Returns the element with the highest priority in the queue,
+   *  or throws an error if there is no element contained in the queue.
+   *
+   *  @return   the element with the highest priority.
+   */
+  @deprecated("Use `head` instead.")
   override def max: A = synchronized { super.max }
 
   /** Removes all elements from the queue. After this operation is completed,