BitSet.cpp
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- /*
- * The Apache Software License, Version 1.1
- *
- * Copyright (c) 1999-2000 The Apache Software Foundation. All rights
- * reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * 3. The end-user documentation included with the redistribution,
- * if any, must include the following acknowledgment:
- * "This product includes software developed by the
- * Apache Software Foundation (http://www.apache.org/)."
- * Alternately, this acknowledgment may appear in the software itself,
- * if and wherever such third-party acknowledgments normally appear.
- *
- * 4. The names "Xerces" and "Apache Software Foundation" must
- * not be used to endorse or promote products derived from this
- * software without prior written permission. For written
- * permission, please contact apache@apache.org.
- *
- * 5. Products derived from this software may not be called "Apache",
- * nor may "Apache" appear in their name, without prior written
- * permission of the Apache Software Foundation.
- *
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
- * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
- * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
- * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
- * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- * ====================================================================
- *
- * This software consists of voluntary contributions made by many
- * individuals on behalf of the Apache Software Foundation, and was
- * originally based on software copyright (c) 1999, International
- * Business Machines, Inc., http://www.ibm.com . For more information
- * on the Apache Software Foundation, please see
- * <http://www.apache.org/>.
- */
- /*
- * $Log: BitSet.cpp,v $
- * Revision 1.4 2000/03/02 19:54:38 roddey
- * This checkin includes many changes done while waiting for the
- * 1.1.0 code to be finished. I can't list them all here, but a list is
- * available elsewhere.
- *
- * Revision 1.3 2000/02/06 07:48:01 rahulj
- * Year 2K copyright swat.
- *
- * Revision 1.2 1999/12/15 19:38:22 roddey
- * Simple fix to bit ops comments
- *
- * Revision 1.1.1.1 1999/11/09 01:04:09 twl
- * Initial checkin
- *
- * Revision 1.2 1999/11/08 20:45:05 rahul
- * Swat for adding in Product name and CVS comment log variable.
- *
- */
- // ---------------------------------------------------------------------------
- // Includes
- // ---------------------------------------------------------------------------
- #include <util/IllegalArgumentException.hpp>
- #include <util/ArrayIndexOutOfBoundsException.hpp>
- #include <util/BitSet.hpp>
- // ---------------------------------------------------------------------------
- // Local const data
- //
- // kBitsPerUnit
- // The number of bits in each of our allocation units, which is a 32
- // bit value in this case.
- //
- // kGrowBy
- // The minimum allocation units to grow the buffer by.
- // ---------------------------------------------------------------------------
- const unsigned int kBitsPerUnit = 32;
- const unsigned int kGrowBy = 1;
- // ---------------------------------------------------------------------------
- // BitSet: Constructors and Destructor
- // ---------------------------------------------------------------------------
- BitSet::BitSet(const unsigned int size) :
- fBits(0)
- , fUnitLen(0)
- {
- ensureCapacity(size);
- }
- BitSet::BitSet(const BitSet& toCopy) :
- fBits(0)
- , fUnitLen(toCopy.fUnitLen)
- {
- fBits = new unsigned long[fUnitLen];
- for (unsigned int i = 0; i < fUnitLen; i++)
- fBits[i] = toCopy.fBits[i];
- }
- BitSet::~BitSet()
- {
- delete [] fBits;
- }
- // ---------------------------------------------------------------------------
- // BitSet: Equality methods
- // ---------------------------------------------------------------------------
- bool BitSet::equals(const BitSet& other) const
- {
- if (this == &other)
- return true;
- if (fUnitLen != other.fUnitLen)
- return false;
- for (unsigned int i = 0; i < fUnitLen; i++)
- {
- if (fBits[i] != other.fBits[i])
- return false;
- }
- return true;
- }
- // ---------------------------------------------------------------------------
- // BitSet: Getter methods
- // ---------------------------------------------------------------------------
- bool BitSet::get(const unsigned int index) const
- {
- const unsigned int unitOfBit = (index / kBitsPerUnit);
- const unsigned int bitWithinUnit = index % kBitsPerUnit;
- //
- // If the index is beyond our size, don't actually expand. Just return
- // false, which is what the state would be if we did expand it.
- //
- bool retVal = false;
- if (unitOfBit <= fUnitLen)
- {
- if (fBits[unitOfBit] & (1 << bitWithinUnit))
- retVal = true;
- }
- return retVal;
- }
- unsigned int BitSet::size() const
- {
- return fUnitLen * kBitsPerUnit;
- }
- // ---------------------------------------------------------------------------
- // BitSet: Setter methods
- // ---------------------------------------------------------------------------
- bool BitSet::allAreCleared() const
- {
- for (unsigned int index = 0; index < fUnitLen; index++)
- {
- if (fBits[index])
- return false;
- }
- return true;
- }
- bool BitSet::allAreSet() const
- {
- for (unsigned int index = 0; index < fUnitLen; index++)
- {
- if (fBits[index] != 0xFFFFFFFF)
- return false;
- }
- return true;
- }
- void BitSet::clearAll()
- {
- // Just zero out all the units
- for (unsigned int index = 0; index < fUnitLen; index++)
- fBits[index] = 0;
- }
- void BitSet::clear(const unsigned int index)
- {
- ensureCapacity(index+1);
- const int unitOfBit = (index / kBitsPerUnit);
- const int bitWithinUnit = index % kBitsPerUnit;
- fBits[unitOfBit] &= ~(1UL << bitWithinUnit);
- }
- void BitSet::set(const unsigned int index)
- {
- ensureCapacity(index+1);
- const int unitOfBit = (index / kBitsPerUnit);
- const int bitWithinUnit = index % kBitsPerUnit;
- fBits[unitOfBit] |= (1UL << bitWithinUnit);
- }
- // ---------------------------------------------------------------------------
- // BitSet: Bitwise logical methods
- // ---------------------------------------------------------------------------
- void BitSet::andWith(const BitSet& other)
- {
- if (fUnitLen < other.fUnitLen)
- ensureCapacity(other.fUnitLen * kBitsPerUnit);
- for (unsigned int index = 0; index < other.fUnitLen; index++)
- fBits[index] &= other.fBits[index];
- }
- void BitSet::orWith(const BitSet& other)
- {
- if (fUnitLen < other.fUnitLen)
- ensureCapacity(other.fUnitLen * kBitsPerUnit);
- for (unsigned int index = 0; index < other.fUnitLen; index++)
- fBits[index] |= other.fBits[index];
- }
- void BitSet::xorWith(const BitSet& other)
- {
- if (fUnitLen < other.fUnitLen)
- ensureCapacity(other.fUnitLen * kBitsPerUnit);
- for (unsigned int index = 0; index < other.fUnitLen; index++)
- fBits[index] ^= other.fBits[index];
- }
- // ---------------------------------------------------------------------------
- // BitSet: Miscellaneous methods
- // ---------------------------------------------------------------------------
- unsigned int BitSet::hash(const unsigned int hashModulus) const
- {
- const unsigned char* pBytes = (const unsigned char*)fBits;
- const int unsigned len = fUnitLen * sizeof(unsigned long);
- unsigned int hashVal = 0;
- for (unsigned int index = 0; index < len; index++)
- {
- hashVal <<= 1;
- hashVal ^= *pBytes;
- }
- return hashVal % hashModulus;
- }
- // ---------------------------------------------------------------------------
- // BitSet: Private methods
- // ---------------------------------------------------------------------------
- void BitSet::ensureCapacity(const unsigned int size)
- {
- // Calculate the units required to hold the passed bit count.
- unsigned int unitsNeeded = size / kBitsPerUnit;
- if (size % kBitsPerUnit)
- unitsNeeded++;
- // If its more than we have, then reallocate
- if (unitsNeeded > fUnitLen)
- {
- // Regrow the unit length by at least the expansion unit
- if (unitsNeeded < (fUnitLen + kGrowBy))
- unitsNeeded = fUnitLen + kGrowBy;
- // Allocate the array, copy the old stuff, and zero the new stuff
- unsigned long* newBits = new unsigned long[unitsNeeded];
- unsigned int index;
- for (index = 0; index < fUnitLen; index++)
- newBits[index] = fBits[index];
- for (; index < unitsNeeded; index++)
- newBits[index] = 0;
- delete [] fBits;
- fBits = newBits;
- fUnitLen = unitsNeeded;
- }
- }