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    1   /*
    2    * Licensed to the Apache Software Foundation (ASF) under one or more
    3    * contributor license agreements.  See the NOTICE file distributed with
    4    * this work for additional information regarding copyright ownership.
    5    * The ASF licenses this file to You under the Apache License, Version 2.0
    6    * (the "License"); you may not use this file except in compliance with
    7    * the License.  You may obtain a copy of the License at
    8    *
    9    *      http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   * Unless required by applicable law or agreed to in writing, software
    12   * distributed under the License is distributed on an "AS IS" BASIS,
    13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   * See the License for the specific language governing permissions and
    15   * limitations under the License.
    16   */
    17
    18  package org.apache.commons.beanutils;
    19
    20  import org.apache.commons.collections.Predicate;
    21  import org.apache.commons.logging.Log;
    22  import org.apache.commons.logging.LogFactory;
    23
    24  import java.lang.reflect.InvocationTargetException;
    25
    26  /***
    27   * <p>Predicate implementation that applies the given <code>Predicate</code>
    28   * to the result of calling the given property getter.
    29   * </p>
    30   */
    31  public class BeanPredicate implements Predicate {
    32
    33      private final Log log = LogFactory.getLog(this.getClass());
    34
    35      /*** Name of the property whose value will be predicated */
    36      private String propertyName;
    37      /*** <code>Predicate</code> to be applied to the property value */
    38      private Predicate predicate;
    39
    40      /***
    41       * Constructs a <code>BeanPredicate</code> that applies the given
    42       * <code>Predicate</code> to the named property value.
    43       * @param propertyName the name of the property whose value is to be predicated,
    44       * not null
    45       * @param predicate the <code>Predicate</code> to be applied,
    46       * not null
    47       */
    48      public BeanPredicate(String propertyName, Predicate predicate) {
    49          this.propertyName = propertyName;
    50          this.predicate = predicate;
    51      }
    52
    53      /***
    54       * Evaluates the given object by applying the {@link #getPredicate()}
    55       * to a property value named by {@link #getPropertyName()}.
    56       *
    57       * @param object The object being evaluated
    58       * @return the result of the predicate evaluation
    59       * @throws IllegalArgumentException when the property cannot be evaluated
    60       */
    61      public boolean evaluate(Object object) {
    62
    63          boolean evaluation = false;
    64
    65          try {
    66              Object propValue = PropertyUtils.getProperty( object, propertyName );
    67              evaluation = predicate.evaluate(propValue);
    68          } catch (IllegalArgumentException e) {
    69              final String errorMsg = "Problem during evaluation.";
    70              log.error("ERROR: " + errorMsg, e);
    71              throw e;
    72          } catch (IllegalAccessException e) {
    73              final String errorMsg = "Unable to access the property provided.";
    74              log.error(errorMsg, e);
    75              throw new IllegalArgumentException(errorMsg);
    76          } catch (InvocationTargetException e) {
    77              final String errorMsg = "Exception occurred in property's getter";
    78              log.error(errorMsg, e);
    79              throw new IllegalArgumentException(errorMsg);
    80          } catch (NoSuchMethodException e) {
    81              final String errorMsg = "Property not found.";
    82              log.error(errorMsg, e);
    83              throw new IllegalArgumentException(errorMsg);
    84          }
    85
    86          return evaluation;
    87      }
    88
    89      /***
    90       * Gets the name of the property whose value is to be predicated.
    91       * in the evaluation.
    92       * @return the property name, not null
    93       */
    94      public String getPropertyName() {
    95          return propertyName;
    96      }
    97
    98      /***
    99       * Sets the name of the property whose value is to be predicated.
    100      * @param propertyName the name of the property whose value is to be predicated,
    101      * not null
    102      */
    103     public void setPropertyName(String propertyName) {
    104         this.propertyName = propertyName;
    105     }
    106
    107     /***
    108      * Gets the <code>Predicate</code> to be applied to the value of the named property
    109      * during {@link #evaluate}.
    110      * @return <code>Predicate</code>, not null
    111      */
    112     public Predicate getPredicate() {
    113         return predicate;
    114     }
    115
    116     /***
    117      * Sets the <code>Predicate</code> to be applied to the value of the named property
    118      * during {@link #evaluate(Object)}.
    119      * @param predicate <code>Predicate</code>, not null
    120      */
    121     public void setPredicate(Predicate predicate) {
    122         this.predicate = predicate;
    123     }
    124
    125 }