Why clear method in org.apache.lucene.search.LRUQueryCache not clear uniqueQueries

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1

the method is below:
public synchronized void clear() {
this.cache.clear();
this.mostRecentlyUsedQueries.clear();
this.onClear();
}

my question is: why not clear uniqueQueries?
since I will make IndicesQueryCache dynamicly configurable I have to clear the previous one.
but if LRUQueryCache's clear method not clear uniqueQueries, it could be memory leak.

2

Because mostRecentlyUsedQueries is actually just uniqueQueries.keySet() it means that clearing the former also clears the latter.

3

thanks very much.

4

Thank you for asking about it, it indeed looks at first like it might be a memory leak.

I pushed a comment to Lucene's sources to help clarify: