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    1   /*
    2    * Copyright 2002-2006 The Apache Software Foundation.
    3    *
    4    * Licensed under the Apache License, Version 2.0 (the "License");
    5    * you may not use this file except in compliance with the License.
    6    * You may obtain a copy of the License at
    7    *
    8    *      http://www.apache.org/licenses/LICENSE-2.0
    9    *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   */
    16  package org.apache.commons.jexl.parser;
    17
    18  import org.apache.commons.jexl.JexlContext;
    19  import org.apache.commons.jexl.util.Coercion;
    20
    21  /***
    22   * GT : a > b.
    23   *
    24   * Follows A.3.6.1 of the JSTL 1.0 specification
    25   *
    26   * @author <a href="mailto:geirm@apache.org">Geir Magnusson Jr.</a>
    27   * @author <a href="mailto:proyal@apache.org">Peter Royal</a>
    28   * @version $Id: ASTGTNode.java 398197 2006-04-29 16:18:04Z dion $
    29   */
    30  public class ASTGTNode extends SimpleNode {
    31      /***
    32       * Create the node given an id.
    33       *
    34       * @param id node id.
    35       */
    36      public ASTGTNode(int id) {
    37          super(id);
    38      }
    39
    40      /***
    41       * Create a node with the given parser and id.
    42       *
    43       * @param p a parser.
    44       * @param id node id.
    45       */
    46      public ASTGTNode(Parser p, int id) {
    47          super(p, id);
    48      }
    49
    50      /*** {@inheritDoc} */
    51      public Object jjtAccept(ParserVisitor visitor, Object data) {
    52          return visitor.visit(this, data);
    53      }
    54
    55      /*** {@inheritDoc} */
    56      public Object value(JexlContext jc) throws Exception {
    57          /*
    58           * now get the values
    59           */
    60
    61          Object left = ((SimpleNode) jjtGetChild(0)).value(jc);
    62          Object right = ((SimpleNode) jjtGetChild(1)).value(jc);
    63
    64          if ((left == right) || (left == null) || (right == null)) {
    65              return Boolean.FALSE;
    66          } else if (Coercion.isFloatingPoint(left)
    67                  || Coercion.isFloatingPoint(right)) {
    68              double leftDouble = Coercion.coerceDouble(left).doubleValue();
    69              double rightDouble = Coercion.coerceDouble(right).doubleValue();
    70
    71              return leftDouble > rightDouble ? Boolean.TRUE : Boolean.FALSE;
    72          } else if (Coercion.isNumberable(left) || Coercion.isNumberable(right)) {
    73              long leftLong = Coercion.coerceLong(left).longValue();
    74              long rightLong = Coercion.coerceLong(right).longValue();
    75
    76              return leftLong > rightLong ? Boolean.TRUE : Boolean.FALSE;
    77          } else if (left instanceof String || right instanceof String) {
    78              String leftString = left.toString();
    79              String rightString = right.toString();
    80
    81              return leftString.compareTo(rightString) > 0 ? Boolean.TRUE
    82                      : Boolean.FALSE;
    83          } else if (left instanceof Comparable) {
    84              return ((Comparable) left).compareTo(right) > 0 ? Boolean.TRUE
    85                      : Boolean.FALSE;
    86          } else if (right instanceof Comparable) {
    87              return ((Comparable) right).compareTo(left) < 0 ? Boolean.TRUE
    88                      : Boolean.FALSE;
    89          }
    90
    91          throw new Exception("Invalid comparison : GT ");
    92      }
    93  }