The java.util.BitSet class implements a vector of bits that grows as needed.Following are the important points about BitSet:
A BitSet is not safe for multithreaded use without external synchronization.
All bits in the set initially have the value false.
Passing a null parameter to any of the methods in a BitSet will result in a NullPointerException.
類聲明
以下是聲明java.util.BitSet class:
public class BitSet
extends Object
implements Cloneable, Serializable
類構造方法
| S.N. | 構造方法 & 詳細描述 |
|---|---|
| 1 | BitSet() This constructor creates a new bit set. |
| 2 | BitSet(int nbits) This constructor creates a bit set whose initial size is large enough to explicitly represent bits with indices in the range 0 through nbits-1. |
類方法
| S.N. | 方法 & 描述 |
|---|---|
| 1 | void and(BitSet set) This method performs a logical AND of this target bit set with the argument bit set. |
| 2 | void andNot(BitSet set) This method clears all of the bits in this BitSet whose corresponding bit is set in the specified BitSet. |
| 3 | int cardinality() This method returns the number of bits set to true in this BitSet. |
| 4 | void clear() This method sets all of the bits in this BitSet to false. |
| 5 | void clear(int bitIndex) This method sets the bit specified by the index to false. |
| 6 | void clear(int fromIndex, int toIndex) This method sets the bits from the specified fromIndex (inclusive) to the specified toIndex (exclusive) to false. |
| 7 | Object clone() This method clones this BitSet and produces a new BitSet that is equal to it. |
| 8 | boolean equals(Object obj) This method compares this object against the specified object. |
| 9 | void flip(int bitIndex) This method sets the bit at the specified index to the complement of its current value. |
| 10 | void flip(int fromIndex, int toIndex) This method sets each bit from the specified fromIndex (inclusive) to the specified toIndex (exclusive) to the complement of its current value. |
| 11 | boolean get(int bitIndex) This method returns the value of the bit with the specified index. |
| 12 | BitSet get(int fromIndex, int toIndex) This method returns a new BitSet composed of bits from this BitSet from fromIndex (inclusive) to toIndex (exclusive). |
| 13 | int hashCode() This method returns the value of the bit with the specified index. |
| 14 | boolean intersects(BitSet set) This method returns true if the specified BitSet has any bits set to true that are also set to true in this BitSet. |
| 15 | boolean isEmpty() This method returns true if this BitSet contains no bits that are set to true. |
| 16 | int length() This method returns the "logical size" of this BitSet: the index of the highest set bit in the BitSet plus one. |
| 17 | int nextClearBit(int fromIndex) This method returns the index of the first bit that is set to false that occurs on or after the specified starting index. |
| 18 | int nextSetBit(int fromIndex) This method returns the index of the first bit that is set to true that occurs on or after the specified starting index. |
| 19 | void or(BitSet set) This method performs a logical OR of this bit set with the bit set argument. |
| 20 | void set(int bitIndex) This method sets the bit at the specified index to true. |
| 21 | void set(int bitIndex, boolean value) This method sets the bit at the specified index to the specified value. |
| 22 | void set(int fromIndex, int toIndex) This method sets the bits from the specified fromIndex (inclusive) to the specified toIndex (exclusive) to true. |
| 23 | void set(int fromIndex, int toIndex, boolean value) This method sets the bits from the specified fromIndex (inclusive) to the specified toIndex (exclusive) to the specified value. |
| 24 | int size() This method returns the number of bits of space actually in use by this BitSet to represent bit values. |
| 25 | String toString() This method returns a string representation of this bit set. |
| 26 | void xor(BitSet set) This method performs a logical XOR of this bit set with the bit set argument. |
方法繼承
此類從以下類繼承了上麵列出的方法
java.util.Object
