BitMap使用案例

package ansj.sun.util;
public class BitMap {

    private static final byte MAX = 127;

    public static void main(String[] args) throws InterruptedException {
        int m = 1578015112 ;

        BitMap hm = new BitMap() ;

        hm.add(m) ;

        System.out.println(hm.contains(m));
    }

    public BitMap() {
        bytes = new byte[12500000];
    }

    public BitMap(int size) {
        bytes = new byte[size];
    }

    private byte[] bytes = null;

    public void add(int i) {
        int r = i / 8;
        int c = i % 8;
        bytes[r] = (byte) (bytes[r] | (1 << c));
    }

    public boolean contains(int i) {
        int r = i / 8;
        int c = i % 8;
        if (((byte) ((bytes[r] >>> c)) & 1) == 1) {
            return true;
        }
        return false;
    }

    public void remove(int i) {
        int r = i / 8;
        int c = i % 8;
        bytes[r] = (byte) (bytes[r] & (((1 << (c + 1)) - 1) ^ MAX));
    }

}