@@ -62,6 +62,8 @@ Race conditions
6262 ] ( #unsafe-concurrent-iteration )
6363 - [ A non-thread-safe collection is * not* returned wrapped in ` Collections.unmodifiable*() ` from
6464 a getter in a thread-safe class?] ( #unsafe-concurrent-iteration )
65+ - [ A synchronized collection is not returned from a getter? in a thread-safe class?
66+ ] ( #unsafe-concurrent-iteration )
6567 - [ Non-trivial mutable object is * not* returned from a getter in a thread-safe class?
6668 ] ( #concurrent-mutation-race )
6769 - [ No separate getters to an atomically updated state?] ( #moving-state-race )
@@ -78,7 +80,9 @@ Race conditions
7880 - [ Concurrent invalidation race is not possible on a lazily initialized state?
7981 ] ( #cache-invalidation-race )
8082 - [ Iteration, Stream pipeline, or copying a ` Collections.synchronized*() ` collection is protected
81- by a lock?] ( #synchronized-collection-iter )
83+ by the lock?] ( #synchronized-collection-iter )
84+ - [ A synchronized collection is passed into ` addAll() ` , ` removeAll() ` , or ` putAll() ` under the
85+ lock?] ( #synchronized-collection-iter )
8286
8387Testing
8488 - [ Unit tests for thread-safe classes are multi-threaded?] ( #multi-threaded-tests )
@@ -717,9 +721,21 @@ more scalable than Guava Cache: see [Sc.9](#caffeine).
717721Stream pipeline using a synchronized collection as a source is protected by ` synchronized (coll) ` ?**
718722See [ the Javadoc] (
719723https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/Collections.html#synchronizedCollection(java.util.Collection) )
720- for examples and details. This also applies to passing synchronized collections into copy
721- constructors or static factory methods of other collections because they implicitly iterate over the
722- source collection.
724+ for examples and details.
725+ 726+ This also applies to passing synchronized collections into:
727+ - Copy constructors of other collections, e. g. ` new ArrayList<>(synchronizedList) `
728+ - Static factory methods of other collections, e. g. ` List.copyOf() ` , ` Set.copyOf() ` ,
729+ ` ImmutableMap.copyOf() `
730+ - Bulk methods on other collections:
731+ - ` otherColl.containsAll(synchronizedColl) `
732+ - ` otherColl.addAll(synchronizedColl) `
733+ - ` otherColl.removeAll(synchronizedColl) `
734+ - ` otherMap.putAll(synchronizedMap) `
735+ - ` otherColl.containsAll(synchronizedMap.keySet()) `
736+ - Etc.
737+ 738+ Because in all these cases there is an implicit iteration on the source collection.
723739
724740See also [ RC.3] ( #unsafe-concurrent-iteration ) about unprotected iteration over non-thread-safe
725741collections.
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