A FuzzyQuery matches terms based on similarity, using the Damerau-Levenshtein algorithm. We are not going into the details of the algorithm as it is outside of our topic. What we need to know is a fuzzy match is measured in the number of edits between terms. FuzzyQuery allows a maximum of 2 edits. For example, between "humptX" and humpty is first edit and between humpXX and humpty are two edits. There is also a requirement that the number of edits must be less than the minimum term length (of either the input term or candidate term). As another example, ab and abcd would not match because the number of edits between the two terms is 2 and it's not greater than the length of ab, which is 2.
Here is a code snippet to demonstrate FuzzyQuery:
FuzzyQuery query = new FuzzyQuery(new Term("content", "humpXX"));