lucene/src/java/org/apache/lucene/util/FixedBitSet.java - manifoldcf-integration-solr-3.x - Git at Google

 /**
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.
  * The ASF licenses this file to You under the Apache License, Version 2.0
  * (the "License"); you may not use this file except in compliance with
  * the License.  You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package org.apache.lucene.util;

 import java.io.IOException;
 import java.util.Arrays;

 import org.apache.lucene.search.DocIdSet;
 import org.apache.lucene.search.DocIdSetIterator;

 // TODO: maybe merge with BitVector?  Problem is BitVector
 // caches its cardinality...

 /** BitSet of fixed length (numBits), backed by accessible
  *  ({@link #getBits}) long[], accessed with an int index,
  *  implementing Bits and DocIdSet.  Unlike {@link
  *  OpenBitSet} this bit set does not auto-expand, cannot
  *  handle long index, and does not have fastXX/XX variants
  *  (just X).
  *
  * @lucene.internal
  **/

 public final class FixedBitSet extends DocIdSet implements Bits {
   private final long[] bits;
   private int numBits;

   /** returns the number of 64 bit words it would take to hold numBits */
   public static int bits2words(int numBits) {
     int numLong = numBits >>> 6;
     if ((numBits & 63) != 0) {
       numLong++;
     }
     return numLong;
   }

   public FixedBitSet(int numBits) {
     this.numBits = numBits;
     bits = new long[bits2words(numBits)];
   }

   /** Makes full copy. */
   public FixedBitSet(FixedBitSet other) {
     bits = new long[other.bits.length];
     System.arraycopy(other.bits, 0, bits, 0, bits.length);
     numBits = other.numBits;
   }

   @Override
   public DocIdSetIterator iterator() {
     return new OpenBitSetIterator(bits, bits.length);
   }

   public int length() {
     return numBits;
   }

   /** This DocIdSet implementation is cacheable. */
   @Override
   public boolean isCacheable() {
     return true;
   }

   /** Expert. */
   public long[] getBits() {
     return bits;
   }

   /** Returns number of set bits.  NOTE: this visits every
    *  long in the backing bits array, and the result is not
    *  internally cached! */
   public int cardinality() {
     return (int) BitUtil.pop_array(bits, 0, bits.length);
   }

   public boolean get(int index) {
     assert index >= 0 && index < numBits;
     int i = index >> 6;               // div 64
     // signed shift will keep a negative index and force an
     // array-index-out-of-bounds-exception, removing the need for an explicit check.
     int bit = index & 0x3f;           // mod 64
     long bitmask = 1L << bit;
     return (bits[i] & bitmask) != 0;
   }

   public void set(int index) {
     assert index >= 0 && index < numBits;
     int wordNum = index >> 6;      // div 64
     int bit = index & 0x3f;     // mod 64
     long bitmask = 1L << bit;
     bits[wordNum] |= bitmask;
   }

   public boolean getAndSet(int index) {
     assert index >= 0 && index < numBits;
     int wordNum = index >> 6;      // div 64
     int bit = index & 0x3f;     // mod 64
     long bitmask = 1L << bit;
     boolean val = (bits[wordNum] & bitmask) != 0;
     bits[wordNum] |= bitmask;
     return val;
   }

   public void clear(int index) {
     assert index >= 0 && index < numBits;
     int wordNum = index >> 6;
     int bit = index & 0x03f;
     long bitmask = 1L << bit;
     bits[wordNum] &= ~bitmask;
   }

   public boolean getAndClear(int index) {
     assert index >= 0 && index < numBits;
     int wordNum = index >> 6;      // div 64
     int bit = index & 0x3f;     // mod 64
     long bitmask = 1L << bit;
     boolean val = (bits[wordNum] & bitmask) != 0;
     bits[wordNum] &= ~bitmask;
     return val;
   }

   /** Returns the index of the first set bit starting at the index specified.
    *  -1 is returned if there are no more set bits.
    */
   public int nextSetBit(int index) {
     assert index >= 0 && index < numBits;
     int i = index >> 6;
     int subIndex = index & 0x3f;      // index within the word
     long word = bits[i] >> subIndex;  // skip all the bits to the right of index

     if (word!=0) {
       return (i<<6) + subIndex + BitUtil.ntz(word);
     }

     while(++i < bits.length) {
       word = bits[i];
       if (word != 0) {
         return (i<<6) + BitUtil.ntz(word);
       }
     }

     return -1;
   }

   public int prevSetBit(int index) {
     assert index >= 0 && index < numBits: "index=" + index + " numBits=" + numBits;
     int i = index >> 6;
     final int subIndex = index & 0x3f;  // index within the word
     long word = (bits[i] << (63-subIndex));  // skip all the bits to the left of index

     if (word != 0) {
       return (i << 6) + subIndex - Long.numberOfLeadingZeros(word); // See LUCENE-3197
     }

     while (--i >= 0) {
       word = bits[i];
       if (word !=0 ) {
         return (i << 6) + 63 - Long.numberOfLeadingZeros(word);
       }
     }

     return -1;
   }

   /** Does in-place OR of the bits provided by the
    *  iterator. */
   public void or(DocIdSetIterator iter) throws IOException {
     if (iter instanceof OpenBitSetIterator && iter.docID() == -1) {
       final OpenBitSetIterator obs = (OpenBitSetIterator) iter;
       or(obs.arr, obs.words);
     } else {
       int doc;
       while ((doc = iter.nextDoc()) < numBits) {
         set(doc);
       }
     }
   }

   /** this = this OR other */
   public void or(FixedBitSet other) {
     or(other.bits, other.bits.length);
   }

   private void or(final long[] otherArr, final int otherLen) {
     final long[] thisArr = this.bits;
     int pos = Math.min(thisArr.length, otherLen);
     while (--pos >= 0) {
       thisArr[pos] |= otherArr[pos];
     }
   }

   /** Does in-place AND of the bits provided by the
    *  iterator. */
   public void and(DocIdSetIterator iter) throws IOException {
     if (iter instanceof OpenBitSetIterator && iter.docID() == -1) {
       final OpenBitSetIterator obs = (OpenBitSetIterator) iter;
       and(obs.arr, obs.words);
     } else {
       if (numBits == 0) return;
       int disiDoc, bitSetDoc = nextSetBit(0);
       while (bitSetDoc != -1 && (disiDoc = iter.advance(bitSetDoc)) < numBits) {
         clear(bitSetDoc, disiDoc);
         disiDoc++;
         bitSetDoc = (disiDoc < numBits) ? nextSetBit(disiDoc) : -1;
       }
       if (bitSetDoc != -1) {
         clear(bitSetDoc, numBits);
       }
     }
   }

   /** this = this AND other */
   public void and(FixedBitSet other) {
     and(other.bits, other.bits.length);
   }

   private void and(final long[] otherArr, final int otherLen) {
     final long[] thisArr = this.bits;
     int pos = Math.min(thisArr.length, otherLen);
     while(--pos >= 0) {
       thisArr[pos] &= otherArr[pos];
     }
     if (thisArr.length > otherLen) {
       Arrays.fill(thisArr, otherLen, thisArr.length, 0L);
     }
   }

   /** Does in-place AND NOT of the bits provided by the
    *  iterator. */
   public void andNot(DocIdSetIterator iter) throws IOException {
     if (iter instanceof OpenBitSetIterator && iter.docID() == -1) {
       final OpenBitSetIterator obs = (OpenBitSetIterator) iter;
       andNot(obs.arr, obs.words);
     } else {
       int doc;
       while ((doc = iter.nextDoc()) < numBits) {
         clear(doc);
       }
     }
   }

   /** this = this AND NOT other */
   public void andNot(FixedBitSet other) {
     andNot(other.bits, other.bits.length);
   }

   private void andNot(final long[] otherArr, final int otherLen) {
     final long[] thisArr = this.bits;
     int pos = Math.min(thisArr.length, otherLen);
     while(--pos >= 0) {
       thisArr[pos] &= ~otherArr[pos];
     }
   }

   // NOTE: no .isEmpty() here because that's trappy (ie,
   // typically isEmpty is low cost, but this one wouldn't
   // be)

   /** Flips a range of bits
    *
    * @param startIndex lower index
    * @param endIndex one-past the last bit to flip
    */
   public void flip(int startIndex, int endIndex) {
     assert startIndex >= 0 && startIndex < numBits;
     assert endIndex >= 0 && endIndex <= numBits;
     if (endIndex <= startIndex) {
       return;
     }

     int startWord = startIndex >> 6;
     int endWord = (endIndex-1) >> 6;

     /*** Grrr, java shifting wraps around so -1L>>>64 == -1
      * for that reason, make sure not to use endmask if the bits to flip will
      * be zero in the last word (redefine endWord to be the last changed...)
     long startmask = -1L << (startIndex & 0x3f);     // example: 11111...111000
     long endmask = -1L >>> (64-(endIndex & 0x3f));   // example: 00111...111111
     ***/

     long startmask = -1L << startIndex;
     long endmask = -1L >>> -endIndex;  // 64-(endIndex&0x3f) is the same as -endIndex due to wrap

     if (startWord == endWord) {
       bits[startWord] ^= (startmask & endmask);
       return;
     }

     bits[startWord] ^= startmask;

     for (int i=startWord+1; i<endWord; i++) {
       bits[i] = ~bits[i];
     }

     bits[endWord] ^= endmask;
   }

   /** Sets a range of bits
    *
    * @param startIndex lower index
    * @param endIndex one-past the last bit to set
    */
   public void set(int startIndex, int endIndex) {
     assert startIndex >= 0 && startIndex < numBits;
     assert endIndex >= 0 && endIndex <= numBits;
     if (endIndex <= startIndex) {
       return;
     }

     int startWord = startIndex >> 6;
     int endWord = (endIndex-1) >> 6;

     long startmask = -1L << startIndex;
     long endmask = -1L >>> -endIndex;  // 64-(endIndex&0x3f) is the same as -endIndex due to wrap

     if (startWord == endWord) {
       bits[startWord] |= (startmask & endmask);
       return;
     }

     bits[startWord] |= startmask;
     Arrays.fill(bits, startWord+1, endWord, -1L);
     bits[endWord] |= endmask;
   }

   /** Clears a range of bits.
    *
    * @param startIndex lower index
    * @param endIndex one-past the last bit to clear
    */
   public void clear(int startIndex, int endIndex) {
     assert startIndex >= 0 && startIndex < numBits;
     assert endIndex >= 0 && endIndex <= numBits;
     if (endIndex <= startIndex) {
       return;
     }

     int startWord = startIndex >> 6;
     int endWord = (endIndex-1) >> 6;

     long startmask = -1L << startIndex;
     long endmask = -1L >>> -endIndex;  // 64-(endIndex&0x3f) is the same as -endIndex due to wrap

     // invert masks since we are clearing
     startmask = ~startmask;
     endmask = ~endmask;

     if (startWord == endWord) {
       bits[startWord] &= (startmask | endmask);
       return;
     }

     bits[startWord] &= startmask;
     Arrays.fill(bits, startWord+1, endWord, 0L);
     bits[endWord] &= endmask;
   }

   @Override
   public Object clone() {
     return new FixedBitSet(this);
   }

   /** returns true if both sets have the same bits set */
   @Override
   public boolean equals(Object o) {
     if (this == o) {
       return true;
     }
     if (!(o instanceof FixedBitSet)) {
       return false;
     }
     FixedBitSet other = (FixedBitSet) o;
     if (numBits != other.length()) {
       return false;
     }
     return Arrays.equals(bits, other.bits);
   }

   @Override
   public int hashCode() {
     long h = 0;
     for (int i = bits.length; --i>=0;) {
       h ^= bits[i];
       h = (h << 1) | (h >>> 63); // rotate left
     }
     // fold leftmost bits into right and add a constant to prevent
     // empty sets from returning 0, which is too common.
     return (int) ((h>>32) ^ h) + 0x98761234;
   }
 }
	/**
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package org.apache.lucene.util;

	import java.io.IOException;
	import java.util.Arrays;

	import org.apache.lucene.search.DocIdSet;
	import org.apache.lucene.search.DocIdSetIterator;

	// TODO: maybe merge with BitVector? Problem is BitVector
	// caches its cardinality...

	/** BitSet of fixed length (numBits), backed by accessible
	* ({@link #getBits}) long[], accessed with an int index,
	* implementing Bits and DocIdSet. Unlike {@link
	* OpenBitSet} this bit set does not auto-expand, cannot
	* handle long index, and does not have fastXX/XX variants
	* (just X).
	*
	* @lucene.internal
	**/

	public final class FixedBitSet extends DocIdSet implements Bits {
	private final long[] bits;
	private int numBits;

	/** returns the number of 64 bit words it would take to hold numBits */
	public static int bits2words(int numBits) {
	int numLong = numBits >>> 6;
	if ((numBits & 63) != 0) {
	numLong++;
	}
	return numLong;
	}

	public FixedBitSet(int numBits) {
	this.numBits = numBits;
	bits = new long[bits2words(numBits)];
	}

	/** Makes full copy. */
	public FixedBitSet(FixedBitSet other) {
	bits = new long[other.bits.length];
	System.arraycopy(other.bits, 0, bits, 0, bits.length);
	numBits = other.numBits;
	}

	@Override
	public DocIdSetIterator iterator() {
	return new OpenBitSetIterator(bits, bits.length);
	}

	public int length() {
	return numBits;
	}

	/** This DocIdSet implementation is cacheable. */
	@Override
	public boolean isCacheable() {
	return true;
	}

	/** Expert. */
	public long[] getBits() {
	return bits;
	}

	/** Returns number of set bits. NOTE: this visits every
	* long in the backing bits array, and the result is not
	* internally cached! */
	public int cardinality() {
	return (int) BitUtil.pop_array(bits, 0, bits.length);
	}

	public boolean get(int index) {
	assert index >= 0 && index < numBits;
	int i = index >> 6; // div 64
	// signed shift will keep a negative index and force an
	// array-index-out-of-bounds-exception, removing the need for an explicit check.
	int bit = index & 0x3f; // mod 64
	long bitmask = 1L << bit;
	return (bits[i] & bitmask) != 0;
	}

	public void set(int index) {
	assert index >= 0 && index < numBits;
	int wordNum = index >> 6; // div 64
	int bit = index & 0x3f; // mod 64
	long bitmask = 1L << bit;
	bits[wordNum] \|= bitmask;
	}

	public boolean getAndSet(int index) {
	assert index >= 0 && index < numBits;
	int wordNum = index >> 6; // div 64
	int bit = index & 0x3f; // mod 64
	long bitmask = 1L << bit;
	boolean val = (bits[wordNum] & bitmask) != 0;
	bits[wordNum] \|= bitmask;
	return val;
	}

	public void clear(int index) {
	assert index >= 0 && index < numBits;
	int wordNum = index >> 6;
	int bit = index & 0x03f;
	long bitmask = 1L << bit;
	bits[wordNum] &= ~bitmask;
	}

	public boolean getAndClear(int index) {
	assert index >= 0 && index < numBits;
	int wordNum = index >> 6; // div 64
	int bit = index & 0x3f; // mod 64
	long bitmask = 1L << bit;
	boolean val = (bits[wordNum] & bitmask) != 0;
	bits[wordNum] &= ~bitmask;
	return val;
	}

	/** Returns the index of the first set bit starting at the index specified.
	* -1 is returned if there are no more set bits.
	*/
	public int nextSetBit(int index) {
	assert index >= 0 && index < numBits;
	int i = index >> 6;
	int subIndex = index & 0x3f; // index within the word
	long word = bits[i] >> subIndex; // skip all the bits to the right of index

	if (word!=0) {
	return (i<<6) + subIndex + BitUtil.ntz(word);
	}

	while(++i < bits.length) {
	word = bits[i];
	if (word != 0) {
	return (i<<6) + BitUtil.ntz(word);
	}
	}

	return -1;
	}

	public int prevSetBit(int index) {
	assert index >= 0 && index < numBits: "index=" + index + " numBits=" + numBits;
	int i = index >> 6;
	final int subIndex = index & 0x3f; // index within the word
	long word = (bits[i] << (63-subIndex)); // skip all the bits to the left of index

	if (word != 0) {
	return (i << 6) + subIndex - Long.numberOfLeadingZeros(word); // See LUCENE-3197
	}

	while (--i >= 0) {
	word = bits[i];
	if (word !=0 ) {
	return (i << 6) + 63 - Long.numberOfLeadingZeros(word);
	}
	}

	return -1;
	}

	/** Does in-place OR of the bits provided by the
	* iterator. */
	public void or(DocIdSetIterator iter) throws IOException {
	if (iter instanceof OpenBitSetIterator && iter.docID() == -1) {
	final OpenBitSetIterator obs = (OpenBitSetIterator) iter;
	or(obs.arr, obs.words);
	} else {
	int doc;
	while ((doc = iter.nextDoc()) < numBits) {
	set(doc);
	}
	}
	}

	/** this = this OR other */
	public void or(FixedBitSet other) {
	or(other.bits, other.bits.length);
	}

	private void or(final long[] otherArr, final int otherLen) {
	final long[] thisArr = this.bits;
	int pos = Math.min(thisArr.length, otherLen);
	while (--pos >= 0) {
	thisArr[pos] \|= otherArr[pos];
	}
	}

	/** Does in-place AND of the bits provided by the
	* iterator. */
	public void and(DocIdSetIterator iter) throws IOException {
	if (iter instanceof OpenBitSetIterator && iter.docID() == -1) {
	final OpenBitSetIterator obs = (OpenBitSetIterator) iter;
	and(obs.arr, obs.words);
	} else {
	if (numBits == 0) return;
	int disiDoc, bitSetDoc = nextSetBit(0);
	while (bitSetDoc != -1 && (disiDoc = iter.advance(bitSetDoc)) < numBits) {
	clear(bitSetDoc, disiDoc);
	disiDoc++;
	bitSetDoc = (disiDoc < numBits) ? nextSetBit(disiDoc) : -1;
	}
	if (bitSetDoc != -1) {
	clear(bitSetDoc, numBits);
	}
	}
	}

	/** this = this AND other */
	public void and(FixedBitSet other) {
	and(other.bits, other.bits.length);
	}

	private void and(final long[] otherArr, final int otherLen) {
	final long[] thisArr = this.bits;
	int pos = Math.min(thisArr.length, otherLen);
	while(--pos >= 0) {
	thisArr[pos] &= otherArr[pos];
	}
	if (thisArr.length > otherLen) {
	Arrays.fill(thisArr, otherLen, thisArr.length, 0L);
	}
	}

	/** Does in-place AND NOT of the bits provided by the
	* iterator. */
	public void andNot(DocIdSetIterator iter) throws IOException {
	if (iter instanceof OpenBitSetIterator && iter.docID() == -1) {
	final OpenBitSetIterator obs = (OpenBitSetIterator) iter;
	andNot(obs.arr, obs.words);
	} else {
	int doc;
	while ((doc = iter.nextDoc()) < numBits) {
	clear(doc);
	}
	}
	}

	/** this = this AND NOT other */
	public void andNot(FixedBitSet other) {
	andNot(other.bits, other.bits.length);
	}

	private void andNot(final long[] otherArr, final int otherLen) {
	final long[] thisArr = this.bits;
	int pos = Math.min(thisArr.length, otherLen);
	while(--pos >= 0) {
	thisArr[pos] &= ~otherArr[pos];
	}
	}

	// NOTE: no .isEmpty() here because that's trappy (ie,
	// typically isEmpty is low cost, but this one wouldn't
	// be)

	/** Flips a range of bits
	*
	* @param startIndex lower index
	* @param endIndex one-past the last bit to flip
	*/
	public void flip(int startIndex, int endIndex) {
	assert startIndex >= 0 && startIndex < numBits;
	assert endIndex >= 0 && endIndex <= numBits;
	if (endIndex <= startIndex) {
	return;
	}

	int startWord = startIndex >> 6;
	int endWord = (endIndex-1) >> 6;

	/*** Grrr, java shifting wraps around so -1L>>>64 == -1
	* for that reason, make sure not to use endmask if the bits to flip will
	* be zero in the last word (redefine endWord to be the last changed...)
	long startmask = -1L << (startIndex & 0x3f); // example: 11111...111000
	long endmask = -1L >>> (64-(endIndex & 0x3f)); // example: 00111...111111
	***/

	long startmask = -1L << startIndex;
	long endmask = -1L >>> -endIndex; // 64-(endIndex&0x3f) is the same as -endIndex due to wrap

	if (startWord == endWord) {
	bits[startWord] ^= (startmask & endmask);
	return;
	}

	bits[startWord] ^= startmask;

	for (int i=startWord+1; i<endWord; i++) {
	bits[i] = ~bits[i];
	}

	bits[endWord] ^= endmask;
	}

	/** Sets a range of bits
	*
	* @param startIndex lower index
	* @param endIndex one-past the last bit to set
	*/
	public void set(int startIndex, int endIndex) {
	assert startIndex >= 0 && startIndex < numBits;
	assert endIndex >= 0 && endIndex <= numBits;
	if (endIndex <= startIndex) {
	return;
	}

	int startWord = startIndex >> 6;
	int endWord = (endIndex-1) >> 6;

	long startmask = -1L << startIndex;
	long endmask = -1L >>> -endIndex; // 64-(endIndex&0x3f) is the same as -endIndex due to wrap

	if (startWord == endWord) {
	bits[startWord] \|= (startmask & endmask);
	return;
	}

	bits[startWord] \|= startmask;
	Arrays.fill(bits, startWord+1, endWord, -1L);
	bits[endWord] \|= endmask;
	}

	/** Clears a range of bits.
	*
	* @param startIndex lower index
	* @param endIndex one-past the last bit to clear
	*/
	public void clear(int startIndex, int endIndex) {
	assert startIndex >= 0 && startIndex < numBits;
	assert endIndex >= 0 && endIndex <= numBits;
	if (endIndex <= startIndex) {
	return;
	}

	int startWord = startIndex >> 6;
	int endWord = (endIndex-1) >> 6;

	long startmask = -1L << startIndex;
	long endmask = -1L >>> -endIndex; // 64-(endIndex&0x3f) is the same as -endIndex due to wrap

	// invert masks since we are clearing
	startmask = ~startmask;
	endmask = ~endmask;

	if (startWord == endWord) {
	bits[startWord] &= (startmask \| endmask);
	return;
	}

	bits[startWord] &= startmask;
	Arrays.fill(bits, startWord+1, endWord, 0L);
	bits[endWord] &= endmask;
	}

	@Override
	public Object clone() {
	return new FixedBitSet(this);
	}

	/** returns true if both sets have the same bits set */
	@Override
	public boolean equals(Object o) {
	if (this == o) {
	return true;
	}
	if (!(o instanceof FixedBitSet)) {
	return false;
	}
	FixedBitSet other = (FixedBitSet) o;
	if (numBits != other.length()) {
	return false;
	}
	return Arrays.equals(bits, other.bits);
	}

	@Override
	public int hashCode() {
	long h = 0;
	for (int i = bits.length; --i>=0;) {
	h ^= bits[i];
	h = (h << 1) \| (h >>> 63); // rotate left
	}
	// fold leftmost bits into right and add a constant to prevent
	// empty sets from returning 0, which is too common.
	return (int) ((h>>32) ^ h) + 0x98761234;
	}
	}