RegexFormatter.java

/*
 *
 * Copyright (c) 1998 Sun Microsystems, Inc. All Rights Reserved.
 *
 * Sun grants you ("Licensee") a non-exclusive, royalty free, license to use,
 * modify and redistribute this software in source and binary code form,
 * provided that i) this copyright notice and license appear on all copies of
 * the software; and ii) Licensee does not utilize the software in a manner
 * which is disparaging to Sun.
 *
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING ANY
 * IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR
 * NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE
 * LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING
 * OR DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR ITS
 * LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT,
 * INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER
 * CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF
 * OR INABILITY TO USE SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 *
 * This software is not designed or intended for use in on-line control of
 * aircraft, air traffic, aircraft navigation or aircraft communications; or in
 * the design, construction, operation or maintenance of any nuclear
 * facility. Licensee represents and warrants that it will not use or
 * redistribute the Software for such purposes.
 */    
    
package cz.cvut.fel.restauracefel.library.library_gui;

import java.text.ParseException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.regex.PatternSyntaxException;
import javax.swing.text.DefaultFormatter;

/**
 * A regular expression based implementation of AbstractFormatter.
 */
public class RegexFormatter extends DefaultFormatter {
  private Pattern pattern;

  private Matcher matcher;

  public RegexFormatter() {
    super();
  }

  /**
   * Creates a regular expression based AbstractFormatter.
   * pattern specifies the regular expression that will be used
   * to determine if a value is legal.
   */
  public RegexFormatter(String pattern) throws PatternSyntaxException {
    this();
    setPattern(Pattern.compile(pattern));
  }

  /**
   * Creates a regular expression based AbstractFormatter.
   * pattern specifies the regular expression that will be used
   * to determine if a value is legal.
   */
  public RegexFormatter(Pattern pattern) {
    this();
    setPattern(pattern);
  }

  /**
   * Sets the pattern that will be used to determine if a value is legal.
   */
  public void setPattern(Pattern pattern) {
    this.pattern = pattern;
  }

  /**
   * Returns the Pattern used to determine if a value is legal.
   */
  public Pattern getPattern() {
    return pattern;
  }

  /**
   * Sets the Matcher used in the most recent test if a value is
   * legal.
   */
  protected void setMatcher(Matcher matcher) {
    this.matcher = matcher;
  }

  /**
   * Returns the Matcher from the most test.
   */
  protected Matcher getMatcher() {
    return matcher;
  }

  /**
   * Parses text returning an arbitrary Object. Some formatters
   * may return null.
   * 
   * If a Pattern has been specified and the text completely
   * matches the regular expression this will invoke setMatcher.
   * 
   * @throws ParseException
   *           if there is an error in the conversion
   * @param text
   *          String to convert
   * @return Object representation of text
   */
    @Override
  public Object stringToValue(String text) throws ParseException {
    Pattern pattern = getPattern();

    if (pattern != null) {
      Matcher matcher = pattern.matcher(text);

      if (matcher.matches()) {
        setMatcher(matcher);
        return super.stringToValue(text);
      }
      throw new ParseException("Pattern did not match", 0);
    }
    return text;
  }
}