org.apache.commons.collections.functors.FunctorUtils Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of commons-collections Show documentation
Show all versions of commons-collections Show documentation
Types that extend and augment the Java Collections Framework.
/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2001-2004 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowledgement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgement may appear in the software itself,
* if and wherever such third-party acknowledgements normally appear.
*
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact [email protected].
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* .
*/
package org.apache.commons.collections.functors;
import java.util.Collection;
import java.util.Iterator;
import org.apache.commons.collections.Closure;
import org.apache.commons.collections.Predicate;
import org.apache.commons.collections.Transformer;
/**
* Internal utilities for functors.
*
* @since Commons Collections 3.0
* @version $Revision: 1.5 $ $Date: 2004/01/14 21:43:09 $
*
* @author Stephen Colebourne
*/
class FunctorUtils {
/**
* Restricted constructor.
*/
private FunctorUtils() {
}
/**
* Clone the predicates to ensure that the internal reference can't be messed with.
*
* @param predicates the predicates to copy
* @return the cloned predicates
*/
static Predicate[] copy(Predicate[] predicates) {
if (predicates == null) {
return null;
}
return (Predicate[]) predicates.clone();
}
/**
* Validate the predicates to ensure that all is well.
*
* @param predicates the predicates to validate
*/
static void validate(Predicate[] predicates) {
if (predicates == null) {
throw new IllegalArgumentException("The predicate array must not be null");
}
for (int i = 0; i < predicates.length; i++) {
if (predicates[i] == null) {
throw new IllegalArgumentException("The predicate array must not contain a null predicate, index " + i + " was null");
}
}
}
/**
* Validate the predicates to ensure that all is well.
*
* @param predicates the predicates to validate
*/
static void validateMin2(Predicate[] predicates) {
if (predicates == null) {
throw new IllegalArgumentException("The predicate array must not be null");
}
if (predicates.length < 2) {
throw new IllegalArgumentException(
"At least 2 predicates must be specified in the predicate array, size was " + predicates.length);
}
for (int i = 0; i < predicates.length; i++) {
if (predicates[i] == null) {
throw new IllegalArgumentException("The predicate array must not contain a null predicate, index " + i + " was null");
}
}
}
/**
* Validate the predicates to ensure that all is well.
*
* @param predicates the predicates to validate
* @return predicate array
*/
static Predicate[] validate(Collection predicates) {
if (predicates == null) {
throw new IllegalArgumentException("The predicate collection must not be null");
}
if (predicates.size() < 2) {
throw new IllegalArgumentException(
"At least 2 predicates must be specified in the predicate collection, size was " + predicates.size());
}
// convert to array like this to guarantee iterator() ordering
Predicate[] preds = new Predicate[predicates.size()];
int i = 0;
for (Iterator it = predicates.iterator(); it.hasNext();) {
preds[i] = (Predicate) it.next();
if (preds[i] == null) {
throw new IllegalArgumentException("The predicate collection must not contain a null predicate, index " + i + " was null");
}
i++;
}
return preds;
}
/**
* Clone the closures to ensure that the internal reference can't be messed with.
*
* @param closures the closures to copy
* @return the cloned closures
*/
static Closure[] copy(Closure[] closures) {
if (closures == null) {
return null;
}
return (Closure[]) closures.clone();
}
/**
* Validate the closures to ensure that all is well.
*
* @param closures the closures to validate
*/
static void validate(Closure[] closures) {
if (closures == null) {
throw new IllegalArgumentException("The closure array must not be null");
}
for (int i = 0; i < closures.length; i++) {
if (closures[i] == null) {
throw new IllegalArgumentException("The closure array must not contain a null closure, index " + i + " was null");
}
}
}
/**
* Copy method
*
* @param transformers the transformers to copy
*/
static Transformer[] copy(Transformer[] transformers) {
if (transformers == null) {
return null;
}
return (Transformer[]) transformers.clone();
}
/**
* Validate method
*
* @param transformers the transformers to validate
*/
static void validate(Transformer[] transformers) {
if (transformers == null) {
throw new IllegalArgumentException("The transformer array must not be null");
}
for (int i = 0; i < transformers.length; i++) {
if (transformers[i] == null) {
throw new IllegalArgumentException(
"The transformer array must not contain a null transformer, index " + i + " was null");
}
}
}
}