doublearrayeditor.java

corejava核心技术第8版

package com.horstmann.corejava;

import java.awt.*;
import java.awt.font.*;
import java.awt.geom.*;
import java.beans.*;

/**
 * A custom editor for an array of floating-point numbers.
 * @version 1.21 2007-10-03
 * @author Cay Horstmann
 */
public class DoubleArrayEditor extends PropertyEditorSupport
{
   @Override
   public void setValue(Object value)
   {
      super.setValue(value);
   }
   
   public Component getCustomEditor()
   {
      return new DoubleArrayEditorPanel(this);
   }

   public boolean supportsCustomEditor()
   {
      return true;
   }

   public boolean isPaintable()
   {
      return true;
   }

   public String getAsText()
   {
      return null;
   }

   public void paintValue(Graphics g, Rectangle box)
   {
      Graphics2D g2 = (Graphics2D) g;
      g2.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING,
            RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
      double[] values = (double[]) getValue();
      StringBuilder s = new StringBuilder();
      for (int i = 0; i < 3; i++)
      {
         if (values.length > i) s.append(values[i]);
         if (values.length > i + 1) s.append(", ");
      }
      if (values.length > 3) s.append("...");

      g2.setPaint(Color.white);
      g2.fill(box);
      g2.setPaint(Color.black);
      FontRenderContext context = g2.getFontRenderContext();
      Rectangle2D stringBounds = g2.getFont().getStringBounds(s.toString(), context);
      double w = stringBounds.getWidth();
      double x = box.x;
      if (w < box.width) x += (box.width - w) / 2;
      double ascent = -stringBounds.getY();
      double y = box.y + (box.height - stringBounds.getHeight()) / 2 + ascent;
      g2.drawString(s.toString(), (float) x, (float) y);
   }

   public String getJavaInitializationString()
   {
      double[] values = (double[]) getValue();
      StringBuilder s = new StringBuilder();
      s.append("new double[] {");
      for (int i = 0; i < values.length; i++)
      {
         if (i > 0) s.append(", ");
         s.append(values[i]);
      }
      s.append("}");
      return s.toString();
   }
}