#191: improve unit tests
#191: improve unit tests

hangum/mapdb,olupas/MapDB,binarytemple/mapdb,pettermahlen/mapdb,sumit784/mapdb,mebigfatguy/mapdb,jankotek/MapDB,jankotek/MapDB,ffjiao/mapdb,ringoluo/mapdb,codeaudit/mapdb,lamfire/mapdb,cocosli/mapdb,mebigfatguy/mapdb,morfeo8marc/mapdb,jankotek/mapdb,olupas/MapDB,SleimanJneidi/mapdb,jankotek/mapdb