Hi! Anuj I guess you are asking what is a BitSet class.??? As per the API documentation here is what it states: " This class implements a vector of bits that grows as needed. Each component of the bit set has a boolean value. The bits of a BitSet are indexed by nonnegative integers. Individual indexed bits can be examined, set, or cleared. One BitSet may be used to modify the contents of another BitSet through logical AND, logical inclusive OR, and logical exclusive OR operations. By default, all bits in the set initially have the value false. Every bit set has a current size, which is the number of bits currently in the bit set. " Hope this helps. Latha

[This message has been edited by Latha Kalaga (edited February 01, 2001).]