wholenumberfield.java

这是一个用java和xml编写的流媒体服务器管理软件

/*
 * ====================================================================
 * The Vovida Software License, Version 1.0
 * 
 * Copyright (c) 2000 Vovida Networks, Inc.  All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * 1. Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in
 * the documentation and/or other materials provided with the
 * distribution.
 * 
 * 3. The names "VOCAL", "Vovida Open Communication Application Library",
 * and "Vovida Open Communication Application Library (VOCAL)" must
 * not be used to endorse or promote products derived from this
 * software without prior written permission. For written
 * permission, please contact [e-mail].
 * 
 * 4. Products derived from this software may not be called "VOCAL", nor
 * may "VOCAL" appear in their name, without prior written
 * permission of Vovida Networks, Inc.
 * 
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE AND
 * NON-INFRINGEMENT ARE DISCLAIMED.  IN NO EVENT SHALL VOVIDA
 * NETWORKS, INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT DAMAGES
 * IN EXCESS OF $1,000, NOR FOR ANY INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
 * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 * 
 * ====================================================================
 * 
 * This software consists of voluntary contributions made by Vovida
 * Networks, Inc. and many individuals on behalf of Vovida Networks,
 * Inc.  For more information on Vovida Networks, Inc., please see
 * <http://www.vovida.org/>.
 * 
 */
package vocal.ui;

import javax.swing.text.*;

import java.awt.Toolkit;
import java.text.NumberFormat;
import java.text.ParseException;
import java.util.Locale;

// Shamelessly stolen and adapted (very slightly!) from the Sun swing tutorial

// By default, this one is ok empty (differs from host and user fields!)

public class WholeNumberField extends ValidatingField
{

  private Toolkit toolkit;
  private NumberFormat integerFormatter;

  // this one takes a name for the error box, and sets "emptyOk" to
  // false (requires it to be filled)
  public WholeNumberField(String desc)
  {
    super(desc);

    emptyOk = false;
    toolkit = Toolkit.getDefaultToolkit();
    integerFormatter = NumberFormat.getNumberInstance(Locale.US);

    integerFormatter.setParseIntegerOnly(true);
  }

  public WholeNumberField()
  {
    super("Numeric Field");

    emptyOk = true;
    toolkit = Toolkit.getDefaultToolkit();
    integerFormatter = NumberFormat.getNumberInstance(Locale.US);

    integerFormatter.setParseIntegerOnly(true);
  }

  public WholeNumberField(int value, int columns)
  {
    super(columns, "Numeric Field");

    emptyOk = true;
    toolkit = Toolkit.getDefaultToolkit();
    integerFormatter = NumberFormat.getNumberInstance(Locale.US);

    integerFormatter.setParseIntegerOnly(true);
    setValue(value);
  }

  public int getValue()
  {
    int retVal = 0;

    try
    {
      retVal = integerFormatter.parse(getText()).intValue();
    }
    catch (ParseException e)
    {

      // This should never happen because insertString allows
      // only properly formatted data to get in the field.
      toolkit.beep();
    }

    return retVal;
  }

  public void setValue(int value)
  {
    setText(integerFormatter.format(value));
  }

  protected Document createDefaultModel()
  {
    return new WholeNumberDocument();
  }

  protected class WholeNumberDocument extends PlainDocument
  {
    public void insertString(int offs, String str, 
            AttributeSet a) throws BadLocationException
    {

      char[] source = str.toCharArray();
      char[] result = new char[source.length];
      int j = 0;

      for (int i = 0; i < result.length; i++)
      {
        if (Character.isDigit(source[i]))
        {
          result[j++] = source[i];
        }
        else
        {
          toolkit.beep();
        }
      }

      super.insertString(offs, new String(result, 0, j), a);
    }

  }

  public void verifyContent() throws ParseException
  {

    // since we already know that it contains valid input, just
    // check to assure it isn't empty if emptyOk is false

    String contentString = getText();

    if (!emptyOk && (contentString.length() == 0))
    {
      throw new ParseException(getFieldDescription() + " : " 
              + "Field cannot be empty", 0);
    }

  }

  private boolean emptyOk;

  public void setEmptyOk()
  {
    emptyOk = true;
  }

}