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GridBagConstraints.javaAPI DocJava SE 5 API16936Fri Aug 26 14:56:44 BST 2005java.awt

GridBagConstraints.java

/*
 * @(#)GridBagConstraints.java	1.34 04/03/15
 *
 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package java.awt;

/**
 * The <code>GridBagConstraints</code> class specifies constraints 
 * for components that are laid out using the 
 * <code>GridBagLayout</code> class.
 *
 * @version 	1.34, 03/15/04
 * @author Doug Stein
 * @see java.awt.GridBagLayout
 * @since JDK1.0
 */
public class GridBagConstraints implements Cloneable, java.io.Serializable {

   /**
     * Specifies that this component is the next-to-last component in its 
     * column or row (<code>gridwidth</code>, <code>gridheight</code>), 
     * or that this component be placed next to the previously added 
     * component (<code>gridx</code>, <code>gridy</code>). 
     * @see      java.awt.GridBagConstraints#gridwidth
     * @see      java.awt.GridBagConstraints#gridheight
     * @see      java.awt.GridBagConstraints#gridx
     * @see      java.awt.GridBagConstraints#gridy
     */
  public static final int RELATIVE = -1;

   /**
     * Specifies that this component is the 
     * last component in its column or row. 
     */
  public static final int REMAINDER = 0;

   /**
     * Do not resize the component. 
     */
  public static final int NONE = 0;

   /**
     * Resize the component both horizontally and vertically. 
     */
  public static final int BOTH = 1;

   /**
     * Resize the component horizontally but not vertically. 
     */
  public static final int HORIZONTAL = 2;

   /**
     * Resize the component vertically but not horizontally. 
     */
  public static final int VERTICAL = 3;

   /**
    * Put the component in the center of its display area.
    */
  public static final int CENTER = 10;

   /**
     * Put the component at the top of its display area,
     * centered horizontally. 
     */
  public static final int NORTH = 11;

    /**
     * Put the component at the top-right corner of its display area. 
     */
  public static final int NORTHEAST = 12;

    /**
     * Put the component on the right side of its display area, 
     * centered vertically.
     */
  public static final int EAST = 13;

    /**
     * Put the component at the bottom-right corner of its display area. 
     */
  public static final int SOUTHEAST = 14;

    /**
     * Put the component at the bottom of its display area, centered 
     * horizontally. 
     */
  public static final int SOUTH = 15;

   /**
     * Put the component at the bottom-left corner of its display area. 
     */
  public static final int SOUTHWEST = 16;

    /**
     * Put the component on the left side of its display area, 
     * centered vertically.
     */
  public static final int WEST = 17;

   /**
     * Put the component at the top-left corner of its display area. 
     */
  public static final int NORTHWEST = 18;

    /** 
     * Place the component centered along the edge of its display area
     * associated with the start of a page for the current
     * <code>ComponentOrienation</code>.  Equal to NORTH for horizontal
     * orientations. 
     */
  public static final int PAGE_START = 19;

    /**
     * Place the component centered along the edge of its display area  
     * associated with the end of a page for the current
     * <code>ComponentOrienation</code>.  Equal to SOUTH for horizontal
     * orientations.
     */
  public static final int PAGE_END = 20;

    /**
     * Place the component centered along the edge of its display area where 
     * lines of text would normally begin for the current 
     * <code>ComponentOrienation</code>.  Equal to WEST for horizontal,
     * left-to-right orientations and EAST for horizontal, right-to-left 
     * orientations.
     */
  public static final int LINE_START = 21;

    /**
     * Place the component centered along the edge of its display area where 
     * lines of text would normally end for the current 
     * <code>ComponentOrienation</code>.  Equal to EAST for horizontal,
     * left-to-right orientations and WEST for horizontal, right-to-left 
     * orientations.
     */
  public static final int LINE_END = 22;

    /**
     * Place the component in the corner of its display area where 
     * the first line of text on a page would normally begin for the current 
     * <code>ComponentOrienation</code>.  Equal to NORTHWEST for horizontal,
     * left-to-right orientations and NORTHEAST for horizontal, right-to-left 
     * orientations.
     */
  public static final int FIRST_LINE_START = 23;

    /**
     * Place the component in the corner of its display area where 
     * the first line of text on a page would normally end for the current 
     * <code>ComponentOrienation</code>.  Equal to NORTHEAST for horizontal,
     * left-to-right orientations and NORTHWEST for horizontal, right-to-left 
     * orientations.
     */
  public static final int FIRST_LINE_END = 24;

    /**
     * Place the component in the corner of its display area where 
     * the last line of text on a page would normally start for the current 
     * <code>ComponentOrienation</code>.  Equal to SOUTHWEST for horizontal,
     * left-to-right orientations and SOUTHEAST for horizontal, right-to-left 
     * orientations.
     */
  public static final int LAST_LINE_START = 25;

    /**
     * Place the component in the corner of its display area where 
     * the last line of text on a page would normally end for the current 
     * <code>ComponentOrienation</code>.  Equal to SOUTHEAST for horizontal,
     * left-to-right orientations and SOUTHWEST for horizontal, right-to-left 
     * orientations.
     */
  public static final int LAST_LINE_END = 26;

   /**
     * Specifies the cell containing the leading edge of the component's 
     * display area, where the first cell in a row has <code>gridx=0</code>. 
     * The leading edge of a component's display area is its left edge for
     * a horizontal, left-to-right container and its right edge for a
     * horizontal, right-to-left container.
     * The value 
     * <code>RELATIVE</code> specifies that the component be placed 
     * immediately following the component that was added to the container 
     * just before this component was added. 
     * <p>
     * The default value is <code>RELATIVE</code>. 
     * <code>gridx</code> should be a non-negative value.
     * @serial
     * @see #clone()
     * @see java.awt.GridBagConstraints#gridy
     * @see java.awt.ComponentOrientation
     */
  public int gridx;

   /**
     * Specifies the cell at the top of the component's display area, 
     * where the topmost cell has <code>gridy=0</code>. The value 
     * <code>RELATIVE</code> specifies that the component be placed just 
     * below the component that was added to the container just before 
     * this component was added. 
     * <p>
     * The default value is <code>RELATIVE</code>.
     * <code>gridy</code> should be a non-negative value.
     * @serial
     * @see #clone() 
     * @see java.awt.GridBagConstraints#gridx
     */
  public int gridy;

   /**
     * Specifies the number of cells in a row for the component's 
     * display area. 
     * <p>
     * Use <code>REMAINDER</code> to specify that the component's
     * display area will be from <code>gridx</code> to the last
     * cell in the row.
     * Use <code>RELATIVE</code> to specify that the component's
     * display area will be from <code>gridx</code> to the next
     * to the last one in its row.
     * <p>
     * <code>gridwidth</code> should be non-negative and the default
     * value is 1.
     * @serial
     * @see #clone() 
     * @see java.awt.GridBagConstraints#gridheight
     */
  public int gridwidth;

   /**
     * Specifies the number of cells in a column for the component's 
     * display area. 
     * <p>
     * Use <code>REMAINDER</code> to specify that the component's
     * display area will be from <code>gridy</code> to the last
     * cell in the column.
     * Use <code>RELATIVE</code> to specify that the component's
     * display area will be from <code>gridy</code> to the next
     * to the last one in its column.
     * <p>
     * <code>gridheight</code> should be a non-negative value and the
     * default value is 1.
     * @serial
     * @see #clone()
     * @see java.awt.GridBagConstraints#gridwidth
     */
  public int gridheight;

   /**
     * Specifies how to distribute extra horizontal space. 
     * <p>
     * The grid bag layout manager calculates the weight of a column to 
     * be the maximum <code>weightx</code> of all the components in a 
     * column. If the resulting layout is smaller horizontally than the area 
     * it needs to fill, the extra space is distributed to each column in 
     * proportion to its weight. A column that has a weight of zero receives 
     * no extra space. 
     * <p>
     * If all the weights are zero, all the extra space appears between 
     * the grids of the cell and the left and right edges. 
     * <p>
     * The default value of this field is <code>0</code>.
     * <code>weightx</code> should be a non-negative value.
     * @serial
     * @see #clone() 
     * @see java.awt.GridBagConstraints#weighty
     */
  public double weightx;

   /**
     * Specifies how to distribute extra vertical space. 
     * <p>
     * The grid bag layout manager calculates the weight of a row to be 
     * the maximum <code>weighty</code> of all the components in a row. 
     * If the resulting layout is smaller vertically than the area it 
     * needs to fill, the extra space is distributed to each row in 
     * proportion to its weight. A row that has a weight of zero receives no 
     * extra space. 
     * <p>
     * If all the weights are zero, all the extra space appears between 
     * the grids of the cell and the top and bottom edges. 
     * <p>
     * The default value of this field is <code>0</code>. 
     * <code>weighty</code> should be a non-negative value.
     * @serial
     * @see #clone()
     * @see java.awt.GridBagConstraints#weightx
     */
  public double weighty;

   /** 
    * This field is used when the component is smaller than its display
     * area. It determines where, within the display area, to place the
     * component. 
     * <p>
     * There are two kinds of possible values: relative and 
     * absolute.  Relative values are interpreted relative to the container's
     * component orientation property while absolute values are not.  The absolute
     * values are:
     * <code>CENTER</code>, <code>NORTH</code>, <code>NORTHEAST</code>,
     * <code>EAST</code>, <code>SOUTHEAST</code>, <code>SOUTH</code>,
     * <code>SOUTHWEST</code>, <code>WEST</code>, and <code>NORTHWEST</code>.
     * The relative values are: <code>PAGE_START</code>, <code>PAGE_END</code>,
     * <code>LINE_START</code>, <code>LINE_END</code>, 
     * <code>FIRST_LINE_START</code>, <code>FIRST_LINE_END</code>, 
     * <code>LAST_LINE_START</code> and <code>LAST_LINE_END</code>.
     * The default value is <code>CENTER</code>. 
     * @serial
     * @see #clone() 
     * @see java.awt.ComponentOrientation
     */
  public int anchor;

   /**
     * This field is used when the component's display area is larger 
     * than the component's requested size. It determines whether to 
     * resize the component, and if so, how. 
     * <p>
     * The following values are valid for <code>fill</code>: 
     * <p>
     * <ul>
     * <li>
     * <code>NONE</code>: Do not resize the component. 
     * <li>
     * <code>HORIZONTAL</code>: Make the component wide enough to fill 
     *         its display area horizontally, but do not change its height. 
     * <li>
     * <code>VERTICAL</code>: Make the component tall enough to fill its 
     *         display area vertically, but do not change its width. 
     * <li>
     * <code>BOTH</code>: Make the component fill its display area 
     *         entirely. 
     * </ul>
     * <p>
     * The default value is <code>NONE</code>. 
     * @serial
     * @see #clone()
     */
  public int fill;

   /**
     * This field specifies the external padding of the component, the 
     * minimum amount of space between the component and the edges of its 
     * display area. 
     * <p>
     * The default value is <code>new Insets(0, 0, 0, 0)</code>. 
     * @serial
     * @see #clone()
     */
  public Insets insets;

   /**
     * This field specifies the internal padding of the component, how much 
     * space to add to the minimum width of the component. The width of 
     * the component is at least its minimum width plus 
     * <code>ipadx</code> pixels. 
     * <p>
     * The default value is <code>0</code>. 
     * @serial
     * @see #clone()
     * @see java.awt.GridBagConstraints#ipady
     */
  public int ipadx;

   /**
     * This field specifies the internal padding, that is, how much 
     * space to add to the minimum height of the component. The height of 
     * the component is at least its minimum height plus 
     * <code>ipady</code> pixels. 
     * <p>
     * The default value is 0. 
     * @serial
     * @see #clone()
     * @see java.awt.GridBagConstraints#ipadx
     */
  public int ipady;

   /**
     * Temporary place holder for the x coordinate.
     * @serial
     */
  int tempX;
   /**
     * Temporary place holder for the y coordinate.
     * @serial
     */
  int tempY;
   /**
     * Temporary place holder for the Width of the component.
     * @serial
     */
  int tempWidth;
   /**
     * Temporary place holder for the Height of the component.
     * @serial
     */
  int tempHeight;
   /**
     * The minimum width of the component.  It is used to calculate
     * <code>ipady</code>, where the default will be 0.
     * @serial
     * @see #ipady
     */
  int minWidth;
   /**
     * The minimum height of the component. It is used to calculate
     * <code>ipadx</code>, where the default will be 0.
     * @serial
     * @see #ipadx
     */
  int minHeight;

  /*
   * JDK 1.1 serialVersionUID 
   */
  private static final long serialVersionUID = -1000070633030801713L;

   /**
     * Creates a <code>GridBagConstraint</code> object with 
     * all of its fields set to their default value. 
     */
  public GridBagConstraints () {
    gridx = RELATIVE;
    gridy = RELATIVE;
    gridwidth = 1;
    gridheight = 1;

    weightx = 0;
    weighty = 0;
    anchor = CENTER;
    fill = NONE;

    insets = new Insets(0, 0, 0, 0);
    ipadx = 0;
    ipady = 0;
  }

  /**
    * Creates a <code>GridBagConstraints</code> object with
    * all of its fields set to the passed-in arguments.
    * 
    * Note: Because the use of this constructor hinders readability
    * of source code, this constructor should only be used by
    * automatic source code generation tools.
    * 
    * @param gridx	The initial gridx value.
    * @param gridy	The initial gridy value.
    * @param gridwidth	The initial gridwidth value.
    * @param gridheight	The initial gridheight value.
    * @param weightx	The initial weightx value.
    * @param weighty	The initial weighty value.
    * @param anchor	The initial anchor value.
    * @param fill	The initial fill value.
    * @param insets	The initial insets value.
    * @param ipadx	The initial ipadx value.
    * @param ipady	The initial ipady value.
    * 
    * @see java.awt.GridBagConstraints#gridx
    * @see java.awt.GridBagConstraints#gridy
    * @see java.awt.GridBagConstraints#gridwidth
    * @see java.awt.GridBagConstraints#gridheight
    * @see java.awt.GridBagConstraints#weightx
    * @see java.awt.GridBagConstraints#weighty
    * @see java.awt.GridBagConstraints#anchor
    * @see java.awt.GridBagConstraints#fill
    * @see java.awt.GridBagConstraints#insets
    * @see java.awt.GridBagConstraints#ipadx
    * @see java.awt.GridBagConstraints#ipady
    * 
    * @since 1.2
    */
  public GridBagConstraints(int gridx, int gridy,
                            int gridwidth, int gridheight,
                            double weightx, double weighty,
                            int anchor, int fill,
                            Insets insets, int ipadx, int ipady) {
    this.gridx = gridx;
    this.gridy = gridy;
    this.gridwidth = gridwidth;
    this.gridheight = gridheight;
    this.fill = fill;
    this.ipadx = ipadx;
    this.ipady = ipady;
    this.insets = insets;
    this.anchor  = anchor;
    this.weightx = weightx;
    this.weighty = weighty;
  }

   /**
    * Creates a copy of this grid bag constraint.
    * @return     a copy of this grid bag constraint
    */
  public Object clone () {
      try { 
	  GridBagConstraints c = (GridBagConstraints)super.clone();
	  c.insets = (Insets)insets.clone();
	  return c;
      } catch (CloneNotSupportedException e) { 
	  // this shouldn't happen, since we are Cloneable
	  throw new InternalError();
      }
  }
}