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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.commons.beanutils;

import java.lang.reflect.InvocationTargetException;

import org.apache.commons.collections.Predicate;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;


/**
 * 

Predicate that evaluates a property value against a specified value.

*

* An implementation of org.apache.commons.collections.Predicate that evaluates a * property value on the object provided against a specified value and returns true * if equal; false otherwise. * The BeanPropertyValueEqualsPredicate constructor takes two parameters which * determine what property will be evaluated on the target object and what its expected value should * be. *

*
* *
public BeanPropertyValueEqualsPredicate( String propertyName, Object propertyValue )
*
*
*
* Will create a Predicate that will evaluate the target object and return * true if the property specified by propertyName has a value which * is equal to the the value specified by propertyValue. Or return * false otherwise. *
*
*

*

* Note: Property names can be a simple, nested, indexed, or mapped property as defined by * org.apache.commons.beanutils.PropertyUtils. If any object in the property path * specified by propertyName is null then the outcome is based on the * value of the ignoreNull attribute. *

*

* A typical usage might look like: *

 * // create the closure
 * BeanPropertyValueEqualsPredicate predicate =
 *    new BeanPropertyValueEqualsPredicate( "activeEmployee", Boolean.FALSE );
 *
 * // filter the Collection
 * CollectionUtils.filter( peopleCollection, predicate );
 * 
*

*

* This would take a Collection of person objects and filter out any people whose * activeEmployee property is false. Assuming... *

    *
  • * The top level object in the peeopleCollection is an object which represents a * person. *
  • *
  • * The person object has a getActiveEmployee() method which returns * the boolean value for the object's activeEmployee property. *
  • *
*

*

* Another typical usage might look like: *

 * // create the closure
 * BeanPropertyValueEqualsPredicate predicate =
 *    new BeanPropertyValueEqualsPredicate( "personId", "456-12-1234" );
 *
 * // search the Collection
 * CollectionUtils.find( peopleCollection, predicate );
 * 
*

*

* This would search a Collection of person objects and return the first object whose * personId property value equals 456-12-1234. Assuming... *

    *
  • * The top level object in the peeopleCollection is an object which represents a * person. *
  • *
  • * The person object has a getPersonId() method which returns * the value for the object's personId property. *
  • *
*

* * @version $Id$ * @see org.apache.commons.beanutils.PropertyUtils * @see org.apache.commons.collections.Predicate */ public class BeanPropertyValueEqualsPredicate implements Predicate { /** For logging. */ private final Log log = LogFactory.getLog(this.getClass()); /** * The name of the property which will be evaluated when this Predicate is executed. */ private String propertyName; /** * The value that the property specified by propertyName * will be compared to when this Predicate executes. */ private Object propertyValue; /** *

Should null objects in the property path be ignored?

*

* Determines whether null objects in the property path will genenerate an * IllegalArgumentException or not. If set to true then if any objects * in the property path evaluate to null then the * IllegalArgumentException throw by PropertyUtils will be logged but * not rethrown and false will be returned. If set to false then if * any objects in the property path evaluate to null then the * IllegalArgumentException throw by PropertyUtils will be logged and * rethrown. *

*/ private boolean ignoreNull; /** * Constructor which takes the name of the property, its expected value to be used in evaluation, * and assumes ignoreNull to be false. * * @param propertyName The name of the property that will be evaluated against the expected value. * @param propertyValue The value to use in object evaluation. * @throws IllegalArgumentException If the property name provided is null or empty. */ public BeanPropertyValueEqualsPredicate(final String propertyName, final Object propertyValue) { this(propertyName, propertyValue, false); } /** * Constructor which takes the name of the property, its expected value * to be used in evaluation, and a boolean which determines whether null objects in * the property path will genenerate an IllegalArgumentException or not. * * @param propertyName The name of the property that will be evaluated against the expected value. * @param propertyValue The value to use in object evaluation. * @param ignoreNull Determines whether null objects in the property path will * genenerate an IllegalArgumentException or not. * @throws IllegalArgumentException If the property name provided is null or empty. */ public BeanPropertyValueEqualsPredicate(final String propertyName, final Object propertyValue, final boolean ignoreNull) { super(); if ((propertyName != null) && (propertyName.length() > 0)) { this.propertyName = propertyName; this.propertyValue = propertyValue; this.ignoreNull = ignoreNull; } else { throw new IllegalArgumentException("propertyName cannot be null or empty"); } } /** * Evaulates the object provided against the criteria specified when this * BeanPropertyValueEqualsPredicate was constructed. Equality is based on * either reference or logical equality as defined by the property object's equals method. If * any object in the property path leading up to the target property is null then * the outcome will be based on the value of the ignoreNull attribute. By default, * ignoreNull is false and would result in an * IllegalArgumentException if an object in the property path leading up to the * target property is null. * * @param object The object to be evaluated. * @return True if the object provided meets all the criteria for this Predicate; * false otherwise. * @throws IllegalArgumentException If an IllegalAccessException, InvocationTargetException, or * NoSuchMethodException is thrown when trying to access the property specified on the object * provided. Or if an object in the property path provided is null and * ignoreNull is set to false. */ public boolean evaluate(final Object object) { boolean evaluation = false; try { evaluation = evaluateValue(propertyValue, PropertyUtils.getProperty(object, propertyName)); } catch (final IllegalArgumentException e) { final String errorMsg = "Problem during evaluation. Null value encountered in property path..."; if (ignoreNull) { log.warn("WARNING: " + errorMsg + e); } else { final IllegalArgumentException iae = new IllegalArgumentException(errorMsg); if (!BeanUtils.initCause(iae, e)) { log.error(errorMsg, e); } throw iae; } } catch (final IllegalAccessException e) { final String errorMsg = "Unable to access the property provided."; final IllegalArgumentException iae = new IllegalArgumentException(errorMsg); if (!BeanUtils.initCause(iae, e)) { log.error(errorMsg, e); } throw iae; } catch (final InvocationTargetException e) { final String errorMsg = "Exception occurred in property's getter"; final IllegalArgumentException iae = new IllegalArgumentException(errorMsg); if (!BeanUtils.initCause(iae, e)) { log.error(errorMsg, e); } throw iae; } catch (final NoSuchMethodException e) { final String errorMsg = "Property not found."; final IllegalArgumentException iae = new IllegalArgumentException(errorMsg); if (!BeanUtils.initCause(iae, e)) { log.error(errorMsg, e); } throw iae; } return evaluation; } /** * Utility method which evaluates whether the actual property value equals the expected property * value. * * @param expected The expected value. * @param actual The actual value. * @return True if they are equal; false otherwise. */ protected boolean evaluateValue(final Object expected, final Object actual) { return (expected == actual) || ((expected != null) && expected.equals(actual)); } /** * Returns the name of the property which will be evaluated when this Predicate is * executed. * * @return The name of the property which will be evaluated when this Predicate is * executed. */ public String getPropertyName() { return propertyName; } /** * Returns the value that the property specified by propertyName will be compared to * when this Predicate executes. * * @return The value that the property specified by propertyName will be compared to * when this Predicate executes. */ public Object getPropertyValue() { return propertyValue; } /** * Returns the flag which determines whether null objects in the property path will * genenerate an IllegalArgumentException or not. If set to true then * if any objects in the property path evaluate to null then the * IllegalArgumentException throw by PropertyUtils will be logged but * not rethrown and false will be returned. If set to false then if * any objects in the property path evaluate to null then the * IllegalArgumentException throw by PropertyUtils will be logged and * rethrown. * * @return The flag which determines whether null objects in the property path will * genenerate an IllegalArgumentException or not. */ public boolean isIgnoreNull() { return ignoreNull; } }




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