21.2

java.util.BitSet

THE PACKAGE JAVA.UTIL

21.2 The Class

java.util.BitSet

'T is an old maxim in the schools,

That flattery's the food of fools;

Yet now and then your men of wit

Will condescend to take a bit.

 Jonathan Swift,

Cadenus and Vanessa

A

BitSet

 object is a set of bits that grows as needed. The bits of a

BitSet

 are

indexed by nonnegative integers. Each bit can be individually 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.

public final class BitSet implements Cloneable {

public BitSet();

public BitSet(int nbits);

public String toString();

public boolean equals(Object obj)

public int hashCode();

public Object clone();

public boolean get(int bitIndex);

public void set(int bitIndex);

public void clear(int bitIndex);

public void and(BitSet set);

public void or(BitSet set);

public void xor(BitSet set);

public int size();

}

21.2.1

public BitSet()

This constructor initializes a newly created

BitSet

 so that all bits are clear.

21.2.2

public BitSet(int nbits)

This constructor initializes a newly created

BitSet

 so that all bits are clear.

Enough space is reserved to explicitly represent bits with indices in the range

0

through

nbits 1

.

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