layoutcachekey.java

swing编写的库存管理程序。毕业设计类

/**
 * ========================================
 * JFreeReport : a free Java report library
 * ========================================
 *
 * Project Info:  http://www.jfree.org/jfreereport/index.html
 * Project Lead:  Thomas Morgner;
 *
 * (C) Copyright 2000-2003, by Simba Management Limited and Contributors.
 *
 * This library is free software; you can redistribute it and/or modify it under the terms
 * of the GNU Lesser General Public License as published by the Free Software Foundation;
 * either version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this
 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * -------------------
 * LayoutCacheKey.java
 * -------------------
 * (C)opyright 2003, by Thomas Morgner and Contributors.
 *
 * Original Author:  Thomas Morgner;
 * Contributor(s):   David Gilbert (for Simba Management Limited);
 *
 * $Id: LayoutCacheKey.java,v 1.4 2003/09/08 18:11:48 taqua Exp $
 *
 * Changes
 * -------
 * 06.04.2003 : Initial version
 */
package org.jfree.report.layout;

import java.awt.geom.Dimension2D;
import java.awt.geom.Point2D;

import org.jfree.report.Element;
import org.jfree.report.style.ElementStyleSheet;

/**
 * A layout cache key. Does not expect subclasses except the search key
 * class. Dont try to subclass this class (or be doomed once again).
 *
 * @author Thomas Morgner
 */
public class LayoutCacheKey
{
  /** The parent dimensions. */
  private Dimension2D parentDim;

  /** The minimum size. */
  private Dimension2D minSize;

  /** The maximum size. */
  private Dimension2D maxSize;

  /** The preferred size. */
  private Dimension2D prefSize;

  /** The absolute position. */
  private Point2D absPos;

  /** The cached hashcode. */
  private int hashCode;
  /** A flag that defines, whether the cached hashcode is valid. */
  private boolean hashcodeValid;

  /**
   * Default constructor.
   */
  protected LayoutCacheKey()
  {
  }

  /**
   * Creates a new key.
   *
   * @param e  the element.
   * @param parentDim  the parent dimensions.
   */
  public LayoutCacheKey(final Element e, final Dimension2D parentDim)
  {
    setElement(e);
    setParentDim(parentDim);
  }

  /**
   * Returns true if this is a search key, and false otherwise.
   *
   * @return A boolean.
   */
  public boolean isSearchKey()
  {
    return false;
  }

  /**
   * Sets the element.
   *
   * @param e  the element.
   */
  protected void setElement(final Element e)
  {
    if (e == null)
    {
      throw new NullPointerException();
    }
    minSize = (Dimension2D) e.getStyle().getStyleProperty(ElementStyleSheet.MINIMUMSIZE);
    minSize = (Dimension2D) minSize.clone();
    maxSize = (Dimension2D) e.getStyle().getStyleProperty(ElementStyleSheet.MAXIMUMSIZE);
    maxSize = (Dimension2D) maxSize.clone();
    prefSize = (Dimension2D) e.getStyle().getStyleProperty(ElementStyleSheet.PREFERREDSIZE);
    if (prefSize != null)
    {
      prefSize = (Dimension2D) prefSize.clone();
    }
    absPos = (Point2D) e.getStyle().getStyleProperty(StaticLayoutManager.ABSOLUTE_POS);
    if (absPos != null)
    {
      absPos = (Point2D) absPos.clone();
    }
    this.hashcodeValid = false;
  }

  /**
   * Sets the parent dimensions.
   *
   * @param parentDim  the parent dimensions.
   */
  protected void setParentDim(final Dimension2D parentDim)
  {
    if (parentDim == null)
    {
      throw new NullPointerException();
    }
    this.hashcodeValid = false;
    this.parentDim = parentDim;
  }

  /**
   * Returns the parent dimensions.
   *
   * @return The parent dimensions.
   */
  public Dimension2D getParentDim()
  {
    return parentDim;
  }

  /**
   * Tests this object for equality with another object.
   *
   * @param o  the other object.
   *
   * @return A boolean.
   */
  public final boolean equals(final Object o)
  {
    if (this == o)
    {
      return true;
    }
    if (!(o instanceof LayoutCacheKey))
    {
      return false;
    }

    final LayoutCacheKey layoutCacheKey = (LayoutCacheKey) o;

    if (absPos != null ? !absPos.equals(layoutCacheKey.absPos) : layoutCacheKey.absPos != null)
    {
      return false;
    }
    if (maxSize != null ? !maxSize.equals(layoutCacheKey.maxSize) : layoutCacheKey.maxSize != null)
    {
      return false;
    }
    if (minSize != null ? !minSize.equals(layoutCacheKey.minSize) : layoutCacheKey.minSize != null)
    {
      return false;
    }
    if (parentDim != null ? !parentDim.equals(layoutCacheKey.parentDim)
        : layoutCacheKey.parentDim != null)
    {
      return false;
    }
    if (prefSize != null ? !prefSize.equals(layoutCacheKey.prefSize)
        : layoutCacheKey.prefSize != null)
    {
      return false;
    }

    return true;
  }

  /**
   * Returns a hash code.
   *
   * @return A hash code.
   */
  public final int hashCode()
  {
    if (hashcodeValid == false)
    {
      int result;
      result = (parentDim != null ? parentDim.hashCode() : 0);
      result = 29 * result + (minSize != null ? minSize.hashCode() : 0);
      result = 29 * result + (maxSize != null ? maxSize.hashCode() : 0);
      result = 29 * result + (prefSize != null ? prefSize.hashCode() : 0);
      result = 29 * result + (absPos != null ? absPos.hashCode() : 0);
      hashCode = result;
      hashcodeValid = true;
    }
    return hashCode;
  }
}