How to extract all keys from a ConcurrentHashMap in Eclipse MAT(Memory Analyzer Tool)?

I'm analyzing a heap dump using Eclipse MAT and need to extract all the keys from a ConcurrentHashMap<String, Object> object.

Current Situation:

As shown in the screenshot, I have a ConcurrentHashMap object:

Object: subscriptionGroupTable

Type: java.util.concurrent.ConcurrentHashMap @ 0x6c0bce020

The map contains multiple entries (80,904 entries total)

In the MAT tree view, I can see the internal structure:

table → ConcurrentHashMap$Node[]

Individual Node objects with key and value fields

For example, one visible key is "SELF_TEST_C_GROUP" (String @ 0x6c1f0d4a0)

My Question:

What is the correct way to extract all keys from this ConcurrentHashMap in MAT?

I need to get a list of all the String keys stored in this map. I've tried using the Inspector view to navigate the structure manually, but with 80,904 entries, this is not practical.

What I'm Looking For:

An OQL query that can extract all keys, or

A method using MAT's built-in features to export/view all keys

enter image description here

Any guidance would be greatly appreciated!