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;
  
  
  /**
   * Represents a range of integers, [min..max]. 
   * 
   * @specfield min: int
   * @specfield max: int
   * @invariant min <= max
   * @author Emina Torlak
   */
  public abstract class IntRange {
  
  	private IntRange() {	}
  	
  	/**
  	 * Returns the left endpoint of this range.
  	 * @return this.min
  	 */
  	public abstract int min();
  	
  	/**
  	 * Returns the right endpoint of this range.
  	 * @return this.max
  	 */
  	public abstract int max();
  
  	/**
  	 * Returns the number of element in this range.
  	 * @return this.max - this.min + 1
  	 */
  	public int size() {
  		return max() - min() + 1;
  	}
  	
  	/**
  	 * Returns true if the given integer is within 
  	 * this range; otherwise returns false.
  	 * @return i in [min..max]
  	 */
  	public boolean contains(int i) {
  		return i >= min() && i <= max();
  	}
  	
  	/**
  	 * Returns true if this range contains the 
  	 * given range.
  	 * @return this.min <= range.min <= range.max <= this.max
  	 * @throws NullPointerException  range = null
  	 */
  	public boolean contains(IntRange range) {
  		return min() <= range.min() && range.max() <= max();
  	}
  	
  	/**
  	 * Returns true if this and the given range intersect.
  	 * @return some i: int | this.contains(i) && range.contains(i)
  	 * @throws NullPointerException  range = null
  	 */
  	public boolean intersects(IntRange range) {
  		return contains(range.min()) || contains(range.max());
  	}
  	
  	
  	/**
  	 * Returns true if o is an int range with the same endpoints as this.
  	 * @return o in IntRange && o.min==this.min && o.max==this.max
  	 */
  	public boolean equals(Object o) {
  		if (o instanceof IntRange) {
  			final IntRange r = (IntRange) o;
  			return min()==r.min() && max()==r.max();
  		}
  		return false;
  	}
  	
  	/**
  	 * Returns the hash code for this int range.  The implementation
  	 * is guaranteed to obey the Object contract.
  	 * @return the hashcode for this intrange
  	 */
  	public int hashCode() {
  		return min()==max() ? min() : min() ^ max();
  	}
  	
  	public String toString() { 
  		return "[" + min() + ".." + max() + "]";
  	}
  	
  	/**
  	 * Represents an int range that consists of a single point. 
  	 * 
  	 * @invariant  min==max
  	 * @author Emina Torlak
  	 */
  	static final class OnePointRange extends IntRange {
  		private final int min;
  		
  		/**
  		 * Constructs a new one point range.
  		 */
  		OnePointRange(int min) {
  			this.min = min;
  		}
  		
  		@Override
  		public final int min() { return min; }
  		
  		@Override
  		public final int max() { return min; }
  	}
  	
  	/**
  	 * Represents an int range with two distinct end points. 
  	 * 
  	 * @invariant  min < max
  	 * @author Emina Torlak
  	 */
  	static final class TwoPointRange extends IntRange {
  		private final int min, max;
  		
  		/**
  		 * Constructs a new two point range.
  		 * @requires  min < max
  		 */
  		TwoPointRange(int min, int max) {
  			assert min < max;
  			this.min = min;
  			this.max = max;
  		}
  		
  		@Override
  		public final int min() { return min; }
  		
  		@Override
  		public final int max() { return max; }
  	}
  	
  	
  }
  