cvs commit: jakarta-ant/src/main/org/apache/tools/ant EnumeratedAttribute.java

[bo...@locus.apache.org]

bodewig     00/07/12 07:06:18

  Added:       src/main/org/apache/tools/ant EnumeratedAttribute.java
  Log:
  The new helper class itself.
  
  Revision  Changes    Path
  1.1                  jakarta-ant/src/main/org/apache/tools/ant/EnumeratedAttribute.java
  
  Index: EnumeratedAttribute.java
  ===================================================================
  /*
   * The Apache Software License, Version 1.1
   *
   * Copyright (c) 2000 The Apache Software Foundation.  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 end-user documentation included with the redistribution, if
   *    any, must include the following acknowlegement:
   *       "This product includes software developed by the
   *        Apache Software Foundation (http://www.apache.org/)."
   *    Alternately, this acknowlegement may appear in the software itself,
   *    if and wherever such third-party acknowlegements normally appear.
   *
   * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
   *    Foundation" must not be used to endorse or promote products derived
   *    from this software without prior written permission. For written
   *    permission, please contact apache@apache.org.
   *
   * 5. Products derived from this software may not be called "Apache"
   *    nor may "Apache" appear in their names without prior written
   *    permission of the Apache Group.
   *
   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 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 many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   */
  
  package org.apache.tools.ant;
  
  /**
   * Helper class for attributes that can only take one of a fixed list
   * of values.
   *
   * <p>See {@link org.apache.tools.ant.taskdefs.FixCRLF FixCRLF} for an
   * example.
   *
   * @author Stefan Bodewig <a href="mailto:stefan.bodewig@megabit.net">stefan.bodewig@megabit.net</a> 
   */
  public abstract class EnumeratedAttribute {
  
      protected String value;
  
      /**
       * This is the only method a subclass needs to implement.
       *
       * @return an array holding all possible values of the enumeration.
       */
      public abstract String[] getValues();
  
      public EnumeratedAttribute() {}
  
      /**
       * Invoked by {@link IntrospectionHelper IntrospectionHelper}.
       */
      public final void setValue(String value) throws BuildException {
          if (!containsValue(value)) {
              throw new BuildException(value+" is not a legal value for this attribute");
          }
          this.value = value;
      }
  
      /**
       * Is this value included in the enumeration?
       */
      public final boolean containsValue(String value) {
          String[] values = getValues();
          if (values == null || value == null) {
              return false;
          }
          
          for (int i=0; i<values.length; i++) {
              if (value.equals(values[i])) {
                  return true;
              }
          }
          return false;
      }
  
      /**
       * Retrieves the value.
       */
      public final String getValue() {
          return value;
      }
  }