https://DevOpsCloud.io -- Cloud Monk Losang Jinpa, Ph.D., MCSE/MCT, GitOps DevOps Engineer

Java IdentityHashMap.containsKey() is a method that checks if a specific key exists in a Java IdentityHashMap. Unlike Java HashMap, which compares keys using Java equals(), IdentityHashMap uses reference equality, meaning two distinct objects with the same content are treated as different keys if they are not the same instance. Introduced in Java 1997 with Java 1.2, containsKey() is used to check for key existence in maps that rely on identity-based comparison.

https://docs.oracle.com/javase/8/docs/api/java/util/IdentityHashMap.html