JDK 9 has
Map#ofEntries
factory which throws runtime error when provided multiple entries with the same
key.
For eg, the following code is erroneously adding two entries with Foo
as key.
Map<String, String> map = Map.ofEntries(
Map.entry("Foo", "Bar"),
Map.entry("Ping", "Pong"),
Map.entry("Kit", "Kat"),
Map.entry("Foo", "Bar"));
Suppress false positives by adding the suppression annotation @SuppressWarnings("DuplicateMapKeys")
to the enclosing element.