doccheck reports the following:
api/java.base/java/util/doc-files/coll-reference.html:401: id not found: api/java.base/java/util/Collections.html#copy-java.util.List(java.util.List)

Based on the nearby text, and the definitions in Collections.html, the id should be
api/java.base/java/util/Collections.html#copy(java.util.List,java.util.List)