numBits.
- */
+ /** Constructs an OpenBitSet large enough to hold {@code numBits}. */
public OpenBitSet(long numBits) {
this.numBits = numBits;
bits = new long[bits2words(numBits)];
wlen = bits.length;
}
+ /** Constructor: allocates enough space for 64 bits. */
public OpenBitSet() {
this(64);
}
- /** Constructs an OpenBitSet from an existing long[].
- * - * numWords are the number of elements in the array that contain - * set bits (non-zero longs). - * numWords should be <= bits.length, and - * any existing words in the array at position >= numWords should be zero. - * + * The first 64 bits are in long[0], with bit index 0 at the least significant + * bit, and bit index 63 at the most significant. Given a bit index, the word + * containing it is long[index/64], and it is at bit number index%64 within + * that word. + *
+ * numWords are the number of elements in the array that contain set bits
+ * (non-zero longs). numWords should be <= bits.length, and any existing
+ * words in the array at position >= numWords should be zero.
+ *
*/
public OpenBitSet(long[] bits, int numWords) {
+ if (numWords > bits.length) {
+ throw new IllegalArgumentException("numWords cannot exceed bits.length");
+ }
this.bits = bits;
this.wlen = numWords;
this.numBits = wlen * 64;
@@ -150,17 +153,9 @@ public class OpenBitSet extends DocIdSet implements Bits, Cloneable {
/** Expert: returns the long[] storing the bits */
public long[] getBits() { return bits; }
- /** Expert: sets a new long[] to use as the bit storage */
- public void setBits(long[] bits) { this.bits = bits; }
-
/** Expert: gets the number of longs in the array that are in use */
public int getNumWords() { return wlen; }
- /** Expert: sets the number of longs in the array that are in use */
- public void setNumWords(int nWords) { this.wlen=nWords; }
-
-
-
/** Returns true or false for the specified bit index. */
@Override
public boolean get(int index) {
@@ -287,7 +282,7 @@ public class OpenBitSet extends DocIdSet implements Bits, Cloneable {
// since endIndex is one past the end, this is index of the last
// word to be changed.
- int endWord = expandingWordNum(endIndex-1);
+ int endWord = expandingWordNum(endIndex-1);
long startmask = -1L << startIndex;
long endmask = -1L >>> -endIndex; // 64-(endIndex&0x3f) is the same as -endIndex due to wrap
@@ -302,19 +297,14 @@ public class OpenBitSet extends DocIdSet implements Bits, Cloneable {
bits[endWord] |= endmask;
}
-
-
protected int expandingWordNum(long index) {
int wordNum = (int)(index >> 6);
- if (wordNum>=wlen) {
- ensureCapacity(index+1);
- wlen = wordNum+1;
+ if (wordNum >= wlen) {
+ ensureCapacity(index + 1);
}
- assert (numBits = Math.max(numBits, index+1)) >= 0;
return wordNum;
}
-
/** clears a bit.
* The index should be less than the OpenBitSet size.
*/
@@ -519,7 +509,7 @@ public class OpenBitSet extends DocIdSet implements Bits, Cloneable {
// since endIndex is one past the end, this is index of the last
// word to be changed.
- int endWord = expandingWordNum(endIndex-1);
+ int endWord = expandingWordNum(endIndex-1);
/*** Grrr, java shifting wraps around so -1L>>>64 == -1
* for that reason, make sure not to use endmask if the bits to flip will
@@ -833,22 +823,22 @@ public class OpenBitSet extends DocIdSet implements Bits, Cloneable {
return false;
}
-
-
- /** Expand the long[] with the size given as a number of words (64 bit longs).
- * getNumWords() is unchanged by this call.
- */
+ /** Expand the long[] with the size given as a number of words (64 bit longs). */
public void ensureCapacityWords(int numWords) {
- if (bits.length < numWords) {
- bits = ArrayUtil.grow(bits, numWords);
- }
+ bits = ArrayUtil.grow(bits, numWords);
+ wlen = numWords;
+ assert (this.numBits = Math.max(this.numBits, numWords << 6)) >= 0;
}
- /** Ensure that the long[] is big enough to hold numBits, expanding it if necessary.
- * getNumWords() is unchanged by this call.
+ /**
+ * Ensure that the long[] is big enough to hold numBits, expanding it if
+ * necessary.
*/
public void ensureCapacity(long numBits) {
ensureCapacityWords(bits2words(numBits));
+ // ensureCapacityWords sets numBits to a multiple of 64, but we want to set
+ // it to exactly what the app asked.
+ assert (this.numBits = Math.max(this.numBits, numBits)) >= 0;
}
/** Lowers numWords, the number of words in use,
@@ -862,10 +852,9 @@ public class OpenBitSet extends DocIdSet implements Bits, Cloneable {
/** returns the number of 64 bit words it would take to hold numBits */
public static int bits2words(long numBits) {
- return (int)(((numBits-1)>>>6)+1);
+ return (int)(((numBits-1)>>>6)+1);
}
-
/** returns true if both sets have the same bits set */
@Override
public boolean equals(Object o) {
diff --git a/lucene/core/src/test/org/apache/lucene/util/TestOpenBitSet.java b/lucene/core/src/test/org/apache/lucene/util/TestOpenBitSet.java
index f80b5e28d95..32e1b22baa0 100644
--- a/lucene/core/src/test/org/apache/lucene/util/TestOpenBitSet.java
+++ b/lucene/core/src/test/org/apache/lucene/util/TestOpenBitSet.java
@@ -331,6 +331,38 @@ public class TestOpenBitSet extends BaseDocIdSetTestCase