The merge operation is designed to combine two or more indexes into one index to accelerate the search and to simplify the work with indexes. When merging, only the index at which the merge method was called is changed. This index as a result of the operation contains all the documents that were contained in all indexes together. The second index or index repository after the merge can be deleted to free up disk space....indexFolder1 = "c:\\MyIndex1\\" ; String indexFolder2 = "c:\\MyIndex2\\"...documentsFolder1 = "c:\\MyDocuments1\\" ; String documentsFolder2 = "c:\\MyDocuments2\\"...