content: /* 
   * Kodkod -- Copyright (c) 2005-present, Emina Torlak
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   */
  package kodkod.util.ints;
  
  import java.util.NoSuchElementException;
  
  
  /**
   * A skeletal implementation of the IntVector interface.   
   *
   * 
   * @specfield length: int
   * @specfield elements: [0..size) ->one int
   * 
   * @author Emina Torlak
   */
  public abstract class AbstractIntVector extends AbstractIntCollection implements IntVector {
  	
  	/**
  	 * Constructs an empty int vector.
  	 * @ensures no this.elements'
  	 */
  	protected AbstractIntVector() {}
  
      /**
       * {@inheritDoc}
       * @see kodkod.util.ints.IntVector#contains(int)
       */
      public boolean contains(int element) {
      	for(int i = 0, max = size(); i < max; i++) {
      		if (get(i)==element) return true;
      	}
      	return false;
      }
  	
      /**
       * Throws {@link UnsupportedOperationException}.
       * @see kodkod.util.ints.IntVector#set(int,int)
       */
      public int set(int index, int element) {
      	throw new UnsupportedOperationException();
      }
      
      /**
       * {@inheritDoc}
       * @see kodkod.util.ints.IntVector#indexOf(int)
       */
      public int indexOf(int element) {
      	for(int i = 0, length=size(); i < length; i++) {
  			if (get(i)==element) return i;
  		}
  		return -1;
      }
  
     /**
      * {@inheritDoc}
      * @see kodkod.util.ints.IntVector#lastIndexOf(int)
      */
      public int lastIndexOf(int element) {
      	for(int i = size()-1; i >= 0; i--) {
  			if (get(i)==element) return i;
  		}
  		return -1;
      }
      
      /**
       * Calls this.add(this.size(), element)
       * @see kodkod.util.ints.IntVector#add(int)
       * @see kodkod.util.ints.IntVector#add(int,int)
       */
      public boolean add(int element) { 
      	final int length = size();
      	add(length,element);
      	return length != size();
      }
          
     /**
      * Throws {@link UnsupportedOperationException}
      * @see kodkod.util.ints.IntVector#add(int, int)
      */
      public void add(int index, int element) { throw new UnsupportedOperationException(); }
      
      /**
       * Returns the result of calling {@linkplain #addAll(int, IntCollection) this.addAll(size(), c)}.
       * @return this.addAll(size(), c)
       * @see kodkod.util.ints.AbstractIntCollection#addAll(kodkod.util.ints.IntCollection)
       */
      public boolean addAll(IntCollection c) {
      	return addAll(size(), c);
      }
      
      /**
       * Throws an UnsupportedOperationException.
       * @see kodkod.util.ints.IntVector#addAll(int, kodkod.util.ints.IntCollection)
       */
      public boolean addAll(int index, IntCollection c) { throw new UnsupportedOperationException(); }
      
      /**
       * Throws an UnsupportedOperationException.
       * @see kodkod.util.ints.IntVector#removeAt(int)
       */
      public int removeAt(int index) { 
      	throw new UnsupportedOperationException();
      }
         
      /**
       * Calls this.iterator(0, length())
       * @see kodkod.util.ints.IntVector#iterator()
       * @see kodkod.util.ints.IntVector#iterator(int,int)
       */
      public IntIterator iterator() {
      	return iterator(0, size());
      }
      
      /**
       * {@inheritDoc}
       * @see kodkod.util.ints.IntVector#iterator(int, int)
       */
      public IntIterator iterator(int fromIndex, int toIndex) {
      	return fromIndex<=toIndex ? new AscendingIntVectorIterator(fromIndex,toIndex) : 
  			new DescendingIntVectorIterator(fromIndex,toIndex);
      }
         
      /**
       * Returns the hash code value for this vector.  
       *
       * @return the hash code value for this vector.
       * @see Object#hashCode()
       * @see Object#equals(Object)
       * @see #equals(Object)
       */
  	public int hashCode() {
  		final int length = size();
  		int hash = length;
  		for(int i = 0; i < length; i++) {
  			hash = Ints.superFastHashIncremental(get(i), hash);
  		}
  		return Ints.superFastHashAvalanche(hash);
   	}
  
  	/**
       * Compares the specified object with this vector for equality.  Returns
       * <tt>true</tt> if and only if the specified object is also an int vector, both
       * vectors have the same size, and all corresponding pairs of elements in
       * the two vectors are <i>equal</i>.  
       * 
       * @return <tt>true</tt> if the specified object is equal to this vector.
       */
  	public boolean equals(Object o) {
  		if (o==this) return true;
  		if (o instanceof IntVector) {
  			final IntVector l = (IntVector) o;
  			final int length = size();
  			if (l.size()==length) {
  				for (int i = 0; i < length; i++) {
  					if (get(i) != l.get(i)) return false;
  				}
  				return true;
  			}
  		}
  		return false;
  	}
  	
  	/**
  	 * {@inheritDoc}
  	 * @see java.lang.Object#toString()
  	 */
  	public String toString() {
  		final StringBuilder buf = new StringBuilder();
  		buf.append("[");
  		IntIterator itr = iterator();
  		if (itr.hasNext()) buf.append(itr.next());
  		while(itr.hasNext()) {
  			buf.append(", ");
  			buf.append(itr.next());
  		}
  		buf.append("]");
  		return buf.toString();
  	}
  
      
      private abstract class IntVectorIterator implements IntIterator {
  		int next, end, last;
  		IntVectorIterator(int fromIndex, int toIndex) {
  			next = fromIndex;
  			end = toIndex;
  			last = -1;
  		}
  		public final void remove() {
  			if (last < 0) throw new IllegalStateException();
  			AbstractIntVector.this.removeAt(last);
  			next = last;
  			last = -1;
  		}
  	}
  	
  	private final class AscendingIntVectorIterator extends IntVectorIterator {
  		/**
  		 * Constructs a new AscendingIntArrayIterator.
  		 * @requires fromIndex <= toIndex
  		 */
  		AscendingIntVectorIterator(int fromIndex, int toIndex) {
  			super(fromIndex, toIndex);
  		}
  		public boolean hasNext() { return last<Integer.MAX_VALUE && next < end; }
  		public int next() {
  			if (!hasNext()) throw new NoSuchElementException();
  			last = next++;
  			return get(last);
  		}
  	}
  	
  	private final class DescendingIntVectorIterator extends IntVectorIterator {
  		/**
  		 * Constructs a new AscendingIntArrayIterator.
  		 * @requires fromIndex >= toIndex
  		 */
  		DescendingIntVectorIterator(int fromIndex, int toIndex) {
  			super(fromIndex, toIndex);
  		}
  		public boolean hasNext() { return next > end; }
  		public int next() {
  			if (!hasNext()) throw new NoSuchElementException();
  			last = next--;
  			return get(last);
  		}
  	}
  }
  