View Javadoc

    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   * LE : 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: ASTLENode.java 398203 2006-04-29 16:44:55Z dion $
    29   */
    30  public class ASTLENode extends SimpleNode {
    31      /***
    32       * Create the node given an id.
    33       *
    34       * @param id node id.
    35       */
    36      public ASTLENode(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 ASTLENode(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) {
    65              return Boolean.TRUE;
    66          } else if ((left == null) || (right == null)) {
    67              return Boolean.FALSE;
    68          } else if (Coercion.isFloatingPoint(left)
    69                  || Coercion.isFloatingPoint(right)) {
    70              double leftDouble = Coercion.coerceDouble(left).doubleValue();
    71              double rightDouble = Coercion.coerceDouble(right).doubleValue();
    72
    73              return leftDouble <= rightDouble ? Boolean.TRUE : Boolean.FALSE;
    74          } else if (Coercion.isNumberable(left) || Coercion.isNumberable(right)) {
    75              long leftLong = Coercion.coerceLong(left).longValue();
    76              long rightLong = Coercion.coerceLong(right).longValue();
    77
    78              return leftLong <= rightLong ? Boolean.TRUE : Boolean.FALSE;
    79          } else if (left instanceof String || right instanceof String) {
    80              String leftString = left.toString();
    81              String rightString = right.toString();
    82
    83              return leftString.compareTo(rightString) <= 0 ? Boolean.TRUE
    84                      : Boolean.FALSE;
    85          } else if (left instanceof Comparable) {
    86              return ((Comparable) left).compareTo(right) <= 0 ? Boolean.TRUE
    87                      : Boolean.FALSE;
    88          } else if (right instanceof Comparable) {
    89              return ((Comparable) right).compareTo(left) >= 0 ? Boolean.TRUE
    90                      : Boolean.FALSE;
    91          }
    92
    93          throw new Exception("Invalid comparison : LE ");
    94      }
    95
    96  }