    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 *
    031 * @version $Id$
    032 */
    033public class BeanPredicate implements Predicate {
    034
    035    private final Log log = LogFactory.getLog(this.getClass());
    036
    037    /** Name of the property whose value will be predicated */
    038    private String propertyName;
    039    /** <code>Predicate</code> to be applied to the property value */
    040    private Predicate predicate;
    041
    042    /**
    043     * Constructs a <code>BeanPredicate</code> that applies the given
    044     * <code>Predicate</code> to the named property value.
    045     * @param propertyName the name of the property whose value is to be predicated,
    046     * not null
    047     * @param predicate the <code>Predicate</code> to be applied,
    048     * not null
    049     */
    050    public BeanPredicate(final String propertyName, final Predicate predicate) {
    051        this.propertyName = propertyName;
    052        this.predicate = predicate;
    053    }
    054
    055    /**
    056     * Evaluates the given object by applying the {@link #getPredicate()}
    057     * to a property value named by {@link #getPropertyName()}.
    058     *
    059     * @param object The object being evaluated
    060     * @return the result of the predicate evaluation
    061     * @throws IllegalArgumentException when the property cannot be evaluated
    062     */
    063    public boolean evaluate(final Object object) {
    064
    065        boolean evaluation = false;
    066
    067        try {
    068            final Object propValue = PropertyUtils.getProperty( object, propertyName );
    069            evaluation = predicate.evaluate(propValue);
    070        } catch (final IllegalArgumentException e) {
    071            final String errorMsg = "Problem during evaluation.";
    072            log.error("ERROR: " + errorMsg, e);
    073            throw e;
    074        } catch (final IllegalAccessException e) {
    075            final String errorMsg = "Unable to access the property provided.";
    076            log.error(errorMsg, e);
    077            throw new IllegalArgumentException(errorMsg);
    078        } catch (final InvocationTargetException e) {
    079            final String errorMsg = "Exception occurred in property's getter";
    080            log.error(errorMsg, e);
    081            throw new IllegalArgumentException(errorMsg);
    082        } catch (final NoSuchMethodException e) {
    083            final String errorMsg = "Property not found.";
    084            log.error(errorMsg, e);
    085            throw new IllegalArgumentException(errorMsg);
    086        }
    087
    088        return evaluation;
    089    }
    090
    091    /**
    092     * Gets the name of the property whose value is to be predicated.
    093     * in the evaluation.
    094     * @return the property name, not null
    095     */
    096    public String getPropertyName() {
    097        return propertyName;
    098    }
    099
    100    /**
    101     * Sets the name of the property whose value is to be predicated.
    102     * @param propertyName the name of the property whose value is to be predicated,
    103     * not null
    104     */
    105    public void setPropertyName(final String propertyName) {
    106        this.propertyName = propertyName;
    107    }
    108
    109    /**
    110     * Gets the <code>Predicate</code> to be applied to the value of the named property
    111     * during {@link #evaluate}.
    112     * @return <code>Predicate</code>, not null
    113     */
    114    public Predicate getPredicate() {
    115        return predicate;
    116    }
    117
    118    /**
    119     * Sets the <code>Predicate</code> to be applied to the value of the named property
    120     * during {@link #evaluate(Object)}.
    121     * @param predicate <code>Predicate</code>, not null
    122     */
    123    public void setPredicate(final Predicate predicate) {
    124        this.predicate = predicate;
    125    }
    126
    127}