After deep diving into lucene code I found that,
the SpanFirstQuery object just use the SpanPositionRangeQuery object with start position 0 and the given end position from the query.
I am trying to implement the SpanEndQuery in the same way because the End position should be the last position and the start should be taken from the query.
There is a way to get the position of the last term in a specific string field?
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