user to an associated value object thusa map is most appropriate in situations where each key is to be viewed as kind of unique index address for its valuethat isan object that serves as kind of location for that value for exam pleif we wish to store student recordswe would probably want to use student id objects as keys (and disallow two students having the same student idin other wordsthe key associated with an object can be viewed as an "addressfor that object indeedmaps are sometimes referred to as associative storesbecause the key associated with an object determines its "locationin the data structure the map adt since map stores collection of objectsit should be viewed as collection of key-value pairs as an adta map supports the following methodssize()return the number of entries in isempty()test whether is empty get( )if mcontains an entry with key equal to kthen return the value of eelse return null put(kv)if does not have an entry with key equal to kthen add entry (kvto and return nullelsereplace with the existing value of the entry with key equal to and return the old value