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    1   /*
    2    * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/pattern/UnionPattern.java,v 1.7 2005/06/28 13:44:44 elharo Exp $
    3    * $Revision: 1.7 $
    4    * $Date: 2005/06/28 13:44:44 $
    5    *
    6    * ====================================================================
    7    *
    8    * Copyright (C) 2000-2002 bob mcwhirter & James Strachan.
    9    * All rights reserved.
    10   *
    11   * Redistribution and use in source and binary forms, with or without
    12   * modification, are permitted provided that the following conditions
    13   * are met:
    14   *
    15   * 1. Redistributions of source code must retain the above copyright
    16   *    notice, this list of conditions, and the following disclaimer.
    17   *
    18   * 2. Redistributions in binary form must reproduce the above copyright
    19   *    notice, this list of conditions, and the disclaimer that follows
    20   *    these conditions in the documentation and/or other materials
    21   *    provided with the distribution.
    22   *
    23   * 3. The name "Jaxen" must not be used to endorse or promote products
    24   *    derived from this software without prior written permission.  For
    25   *    written permission, please contact license@jaxen.org.
    26   *
    27   * 4. Products derived from this software may not be called "Jaxen", nor
    28   *    may "Jaxen" appear in their name, without prior written permission
    29   *    from the Jaxen Project Management (pm@jaxen.org).
    30   *
    31   * In addition, we request (but do not require) that you include in the
    32   * end-user documentation provided with the redistribution and/or in the
    33   * software itself an acknowledgement equivalent to the following:
    34   *     "This product includes software developed by the
    35   *      Jaxen Project <http://www.jaxen.org/>."
    36   * Alternatively, the acknowledgment may be graphical using the logos
    37   * available at http://www.jaxen.org/
    38   *
    39   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
    40   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
    41   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    42   * DISCLAIMED.  IN NO EVENT SHALL THE Jaxen AUTHORS OR THE PROJECT
    43   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    44   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
    45   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
    46   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
    47   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
    48   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
    49   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
    50   * SUCH DAMAGE.
    51   *
    52   * ====================================================================
    53   * This software consists of voluntary contributions made by many
    54   * individuals on behalf of the Jaxen Project and was originally
    55   * created by bob mcwhirter <bob@werken.com> and
    56   * James Strachan <jstrachan@apache.org>.  For more information on the
    57   * Jaxen Project, please see <http://www.jaxen.org/>.
    58   *
    59   * $Id: UnionPattern.java,v 1.7 2005/06/28 13:44:44 elharo Exp $
    60   */
    61
    62  package org.jaxen.pattern;
    63
    64  import org.jaxen.Context;
    65  import org.jaxen.JaxenException;
    66
    67  /*** <p><code>UnionPattern</code> represents a union pattern.</p>
    68    *
    69    * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
    70    * @version $Revision: 1.7 $
    71    */
    72  public class UnionPattern extends Pattern {
    73
    74      private Pattern lhs;
    75      private Pattern rhs;
    76      private short nodeType = ANY_NODE;
    77      private String matchesNodeName = null;
    78
    79
    80      public UnionPattern()
    81      {
    82      }
    83
    84      public UnionPattern(Pattern lhs, Pattern rhs)
    85      {
    86          this.lhs = lhs;
    87          this.rhs = rhs;
    88          init();
    89      }
    90
    91
    92      public Pattern getLHS()
    93      {
    94          return lhs;
    95      }
    96
    97      public void setLHS(Pattern lhs)
    98      {
    99          this.lhs = lhs;
    100         init();
    101     }
    102
    103     public Pattern getRHS()
    104     {
    105         return rhs;
    106     }
    107
    108     public void setRHS(Pattern rhs)
    109     {
    110         this.rhs = rhs;
    111         init();
    112     }
    113
    114
    115     // Pattern interface
    116     //-------------------------------------------------------------------------
    117
    118     /*** @return true if the pattern matches the given node
    119       */
    120     public boolean matches( Object node, Context context ) throws JaxenException
    121     {
    122         return lhs.matches( node, context ) || rhs.matches( node, context );
    123     }
    124
    125     public Pattern[] getUnionPatterns()
    126     {
    127         return new Pattern[] { lhs, rhs };
    128     }
    129
    130
    131     public short getMatchType()
    132     {
    133         return nodeType;
    134     }
    135
    136
    137     public String getMatchesNodeName()
    138     {
    139         return matchesNodeName;
    140     }
    141
    142
    143     public Pattern simplify()
    144     {
    145         this.lhs = lhs.simplify();
    146         this.rhs = rhs.simplify();
    147         init();
    148         return this;
    149     }
    150
    151     public String getText()
    152     {
    153         return lhs.getText() + " | " + rhs.getText();
    154     }
    155
    156     public String toString()
    157     {
    158         return super.toString() + "[ lhs: " + lhs + " rhs: " + rhs + " ]";
    159     }
    160
    161     // Implementation methods
    162     //-------------------------------------------------------------------------
    163     private void init()
    164     {
    165         short type1 = lhs.getMatchType();
    166         short type2 = rhs.getMatchType();
    167         this.nodeType = ( type1 == type2 ) ? type1 : ANY_NODE;
    168
    169         String name1 = lhs.getMatchesNodeName();
    170         String name2 = rhs.getMatchesNodeName();
    171
    172         this.matchesNodeName = null;
    173         if ( name1 != null && name2 != null && name1.equals( name2 ) )
    174         {
    175             this.matchesNodeName = name1;
    176         }
    177     }
    178 }