GridBagConstraints

/*GBC - A convenience class to tame the GridBagLayoutCopyright (C) 2002 Cay S. Horstmann (http://horstmann.com)This program is free software; you can redistribute it and/or modifyit under the terms of the GNU General Public License as published bythe Free Software Foundation; either version 2 of the License, or(at your option) any later version.This program is distributed in the hope that it will be useful,but WITHOUT ANY WARRANTY; without even the implied warranty ofMERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See theGNU General Public License for more details.You should have received a copy of the GNU General Public Licensealong with this program; if not, write to the Free SoftwareFoundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA*/import java.awt.*;/** This class simplifies the use of the GridBagConstraints class.*/public class GBC extends GridBagConstraints { /** Constructs a GBC with a given gridx and gridy position and all other grid bag constraint values set to the default. @param gridx the gridx position @param gridy the gridy position */ public GBC(int gridx, int gridy) { this.gridx = gridx; this.gridy = gridy; } /** Sets the cell spans. @param gridwidth the cell span in x-direction @param gridheight the cell span in y-direction @return this object for further modification */ public GBC setSpan(int gridwidth, int gridheight) { this.gridwidth = gridwidth; this.gridheight = gridheight; return this; } /** Sets the anchor. @param anchor the anchor value @return this object for further modification */ public GBC setAnchor(int anchor) { this.anchor = anchor; return this; } /** Sets the fill direction. @param fill the fill direction @return this object for further modification */ public GBC setFill(int fill) { this.fill = fill; return this; } /** Sets the cell weights. @param weightx the cell weight in x-direction @param weighty the cell weight in y-direction @return this object for further modification */ public GBC setWeight(double weightx, double weighty) { this.weightx = weightx; this.weighty = weighty; return this; } /** Sets the insets of this cell. @param distance the spacing to use in all directions @return this object for further modification */ public GBC setInsets(int distance) { this.insets = new java.awt.Insets( distance, distance, distance, distance); return this; } /** Sets the insets of this cell. @param top the spacing to use on top @param left the spacing to use to the left @param bottom the spacing to use on the bottom @param right the spacing to use to the right @return this object for further modification */ public GBC setInsets(int top, int left, int bottom, int right) { this.insets = new java.awt.Insets( top, left, bottom, right); return this; } /** Sets the internal padding @param ipadx the internal padding in x-direction @param ipady the internal padding in y-direction @return this object for further modification */ public GBC setIpad(int ipadx, int ipady) { this.ipadx = ipadx; this.ipady = ipady; return this; }}

引自java2核心技术 因为编写GridBagLayout的约束代码很麻烦，而这个类能够简化。