package org.joni;
public final class BitSet {
static final int BITS_PER_BYTE = 8;
public static final int SINGLE_BYTE_SIZE = (1 << BITS_PER_BYTE);
public static final int BITS_IN_ROOM = 4 * BITS_PER_BYTE;
public static final int BITSET_SIZE = (SINGLE_BYTE_SIZE / BITS_IN_ROOM);
static final int ROOM_SHIFT = log2(BITS_IN_ROOM);
public final int[] bits = new int[BITSET_SIZE];
public boolean at(int pos) {
return (bits[pos >>> ROOM_SHIFT] & bit(pos)) != 0;
}
public void set(ScanEnvironment env, int pos) {
if (at(pos)) env.ccDuplicateWarn();
set(pos);
}
public void set(int pos) {
bits[pos >>> ROOM_SHIFT] |= bit(pos);
}
public void clear(int pos) {
bits[pos >>> ROOM_SHIFT] &= ~bit(pos);
}
public void invert(int pos) {
bits[pos >>> ROOM_SHIFT] ^= bit(pos);
}
public void clear() {
for (int i=0; i<BITSET_SIZE; i++) bits[i]=0;
}
public boolean isEmpty() {
for (int i=0; i<BITSET_SIZE; i++) {
if (bits[i] != 0) return false;
}
return true;
}
public void setRange(ScanEnvironment env, int from, int to) {
for (int i=from; i<=to && i < SINGLE_BYTE_SIZE; i++) {
if (env != null && at(i)) env.ccDuplicateWarn();
set(i);
}
}
public void setAll() {
for (int i=0; i<BITSET_SIZE; i++) bits[i] = ~0;
}
public void invert() {
for (int i=0; i<BITSET_SIZE; i++) bits[i] = ~bits[i];
}
public void invertTo(BitSet to) {
for (int i=0; i<BITSET_SIZE; i++) to.bits[i] = ~bits[i];
}
public void and(BitSet other) {
for (int i=0; i<BITSET_SIZE; i++) bits[i] &= other.bits[i];
}
public void or(BitSet other) {
for (int i=0; i<BITSET_SIZE; i++) bits[i] |= other.bits[i];
}
public void copy(BitSet other) {
for (int i=0; i<BITSET_SIZE; i++) bits[i] = other.bits[i];
}
int numOn() {
int num = 0;
for (int i=0; i<SINGLE_BYTE_SIZE; i++) {
if (at(i)) num++;
}
return num;
}
private static int bit(int pos){
return 1 << (pos % SINGLE_BYTE_SIZE);
}
private static int log2(int n){
int log = 0;
while ((n >>>= 1) != 0) log++;
return log;
}
private static final int BITS_TO_STRING_WRAP = 4;
public String toString() {
StringBuilder buffer = new StringBuilder();
buffer.append("BitSet");
for (int i=0; i<SINGLE_BYTE_SIZE; i++) {
if ((i % (SINGLE_BYTE_SIZE / BITS_TO_STRING_WRAP)) == 0) buffer.append("\n ");
buffer.append(at(i) ? "1" : "0");
}
return buffer.toString();
}
}