org.robolectric.shadows.NativeBitSet64 Maven / Gradle / Ivy
Show all versions of shadows-framework Show documentation
package org.robolectric.shadows;
/**
* Transliteration of native BitSet64.
*
* Unlike the native code stores value inline as opposed to a manipulating data via series of
* static methods passed values by reference.
*
* @see "system/core/libutils/include/utils/BitSet.h"
*/
public class NativeBitSet64 {
private long value;
NativeBitSet64(long value) {
this.value = value;
}
NativeBitSet64(NativeBitSet64 other) {
this.value = other.value;
}
NativeBitSet64() {
this(0);
}
/** Gets the value associated with a particular bit index. */
static long valueForBit(int n) {
return 0x8000000000000000L >>> n;
}
/** Clears the bit set. */
void clear() {
value = 0;
}
/** Returns the number of marked bits in the set. */
int count() {
int count = 0;
for (int n = 0; n < 64; n++) {
if (hasBit(n)) {
count++;
}
}
return count;
}
/** Returns true if the bit set does not contain any marked bits. */
boolean isEmpty() {
return value == 0;
}
/** Returns true if the specified bit is marked. */
boolean hasBit(int n) {
return (value & valueForBit(n)) != 0;
}
/** Marks the specified bit. */
void markBit(int n) {
value |= valueForBit(n);
}
/** Clears the specified bit. */
void clearBit(int n) {
value &= ~valueForBit(n);
}
/** Finds the first marked bit in the set. Result is undefined if all bits are unmarked. */
int firstMarkedBit() {
for (int n = 0; n < 64; n++) {
if (hasBit(n)) {
return n;
}
}
return 0;
}
/**
* Finds the first marked bit in the set and clears it. Returns the bit index. Result is undefined
* if all bits are unmarked.
*/
int clearFirstMarkedBit() {
int n = firstMarkedBit();
clearBit(n);
return n;
}
/**
* Gets the index of the specified bit in the set, which is the number of marked bits that appear
* before the specified bit.
*/
int getIndexOfBit(int n) {
// return __builtin_popcountll(value & ~(0xffffffffffffffffULL >> n));
int numMarkedBits = 0;
for (int i = 0; i < n; i++) {
if (hasBit(i)) {
numMarkedBits++;
}
}
return numMarkedBits;
}
public void setValue(long l) {
value = l;
}
public long getValue() {
return value;
}
}