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1
54 package org.logicalcobwebs.cglib.core;
55
56 public class TinyBitSet {
57 private static int[] T = new int[256];
58 private int value = 0;
59
60 private static int gcount(int x) {
61 int c = 0;
62 while (x != 0) {
63 c++;
64 x &= (x - 1);
65 }
66 return c;
67 }
68
69 static {
70 for(int j = 0; j < 256; j++) {
71 T[j] = gcount(j);
72 }
73 }
74
75 private static int topbit(int i) {
76 int j;
77 for (j = 0; i != 0; i ^= j) {
78 j = i & -i;
79 }
80 return j;
81 }
82
83 private static int log2(int i) {
84 int j = 0;
85 for (j = 0; i != 0; i >>= 1) {
86 j++;
87 }
88 return j;
89 }
90
91 public int length() {
92 return log2(topbit(value));
93 }
94
95 public int cardinality() {
96 int w = value;
97 int c = 0;
98 while (w != 0) {
99 c += T[w & 255];
100 w >>= 8;
101 }
102 return c;
103 }
104
105 public boolean get(int index) {
106 return (value & (1 << index)) != 0;
107 }
108
109 public void set(int index) {
110 value |= (1 << index);
111 }
112
113 public void clear(int index) {
114 value &= ~(1 << index);
115 }
116 }
117 |
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