001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.beanutils;
019
020import org.apache.commons.collections.Predicate;
021import org.apache.commons.logging.Log;
022import org.apache.commons.logging.LogFactory;
023
024import java.lang.reflect.InvocationTargetException;
025
026/**
027 * <p>Predicate implementation that applies the given <code>Predicate</code>
028 * to the result of calling the given property getter.
029 * </p>
030 */
031public class BeanPredicate implements Predicate {
032   
033    private final Log log = LogFactory.getLog(this.getClass());
034    
035    /** Name of the property whose value will be predicated */
036    private String propertyName;
037    /** <code>Predicate</code> to be applied to the property value */
038    private Predicate predicate;
039
040    /**
041     * Constructs a <code>BeanPredicate</code> that applies the given
042     * <code>Predicate</code> to the named property value.
043     * @param propertyName the name of the property whose value is to be predicated,
044     * not null
045     * @param predicate the <code>Predicate</code> to be applied,
046     * not null
047     */
048    public BeanPredicate(String propertyName, Predicate predicate) {
049        this.propertyName = propertyName;
050        this.predicate = predicate;
051    }
052
053    /**
054     * Evaluates the given object by applying the {@link #getPredicate()}
055     * to a property value named by {@link #getPropertyName()}.
056     *
057     * @param object The object being evaluated
058     * @return the result of the predicate evaluation
059     * @throws IllegalArgumentException when the property cannot be evaluated
060     */
061    public boolean evaluate(Object object) {
062       
063        boolean evaluation = false;
064
065        try {
066            Object propValue = PropertyUtils.getProperty( object, propertyName );
067            evaluation = predicate.evaluate(propValue);
068        } catch (IllegalArgumentException e) {
069            final String errorMsg = "Problem during evaluation.";
070            log.error("ERROR: " + errorMsg, e);
071            throw e;
072        } catch (IllegalAccessException e) {
073            final String errorMsg = "Unable to access the property provided.";
074            log.error(errorMsg, e);
075            throw new IllegalArgumentException(errorMsg);
076        } catch (InvocationTargetException e) {
077            final String errorMsg = "Exception occurred in property's getter";
078            log.error(errorMsg, e);
079            throw new IllegalArgumentException(errorMsg);
080        } catch (NoSuchMethodException e) {
081            final String errorMsg = "Property not found.";
082            log.error(errorMsg, e);
083            throw new IllegalArgumentException(errorMsg);
084        }
085
086        return evaluation;
087    }
088
089    /**
090     * Gets the name of the property whose value is to be predicated.
091     * in the evaluation.
092     * @return the property name, not null
093     */ 
094    public String getPropertyName() {
095        return propertyName;
096    }
097
098    /** 
099     * 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}