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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.collections4.list;
import java.util.Collection;
import java.util.List;
import java.util.ListIterator;
import org.apache.commons.collections4.Predicate;
import org.apache.commons.collections4.collection.PredicatedCollection;
import org.apache.commons.collections4.iterators.AbstractListIteratorDecorator;
/**
* Decorates another List to validate that all additions
* match a specified predicate.
*
* This list exists to provide validation for the decorated list.
* It is normally created to decorate an empty list.
* If an object cannot be added to the list, an IllegalArgumentException is thrown.
*
* One usage would be to ensure that no null entries are added to the list.
*
* {@code
* List list =
* PredicatedList.predicatedList(new ArrayList(), PredicateUtils.notNullPredicate());
* }
*
*
* This class is Serializable from Commons Collections 3.1.
*
* @since 3.0
*/
public class PredicatedList extends PredicatedCollection implements List {
/** Serialization version */
private static final long serialVersionUID = -5722039223898659102L;
/**
* Factory method to create a predicated (validating) list.
*
* If there are any elements already in the list being decorated, they
* are validated.
*
* @param the type of the elements in the list
* @param list the list to decorate, must not be null
* @param predicate the predicate to use for validation, must not be null
* @return a new predicated list
* @throws NullPointerException if list or predicate is null
* @throws IllegalArgumentException if the list contains invalid elements
* @since 4.0
*/
public static PredicatedList predicatedList(final List list, final Predicate predicate) {
return new PredicatedList<>(list, predicate);
}
//-----------------------------------------------------------------------
/**
* Constructor that wraps (not copies).
*
* If there are any elements already in the list being decorated, they
* are validated.
*
* @param list the list to decorate, must not be null
* @param predicate the predicate to use for validation, must not be null
* @throws NullPointerException if list or predicate is null
* @throws IllegalArgumentException if the list contains invalid elements
*/
protected PredicatedList(final List list, final Predicate predicate) {
super(list, predicate);
}
/**
* Gets the list being decorated.
*
* @return the decorated list
*/
@Override
protected List decorated() {
return (List) super.decorated();
}
@Override
public boolean equals(final Object object) {
return object == this || decorated().equals(object);
}
@Override
public int hashCode() {
return decorated().hashCode();
}
//-----------------------------------------------------------------------
@Override
public E get(final int index) {
return decorated().get(index);
}
@Override
public int indexOf(final Object object) {
return decorated().indexOf(object);
}
@Override
public int lastIndexOf(final Object object) {
return decorated().lastIndexOf(object);
}
@Override
public E remove(final int index) {
return decorated().remove(index);
}
//-----------------------------------------------------------------------
@Override
public void add(final int index, final E object) {
validate(object);
decorated().add(index, object);
}
@Override
public boolean addAll(final int index, final Collection coll) {
for (final E aColl : coll) {
validate(aColl);
}
return decorated().addAll(index, coll);
}
@Override
public ListIterator listIterator() {
return listIterator(0);
}
@Override
public ListIterator listIterator(final int i) {
return new PredicatedListIterator(decorated().listIterator(i));
}
@Override
public E set(final int index, final E object) {
validate(object);
return decorated().set(index, object);
}
@Override
public List subList(final int fromIndex, final int toIndex) {
final List sub = decorated().subList(fromIndex, toIndex);
return new PredicatedList<>(sub, predicate);
}
/**
* Inner class Iterator for the PredicatedList
*/
protected class PredicatedListIterator extends AbstractListIteratorDecorator {
/**
* Create a new predicated list iterator.
*
* @param iterator the list iterator to decorate
*/
protected PredicatedListIterator(final ListIterator iterator) {
super(iterator);
}
@Override
public void add(final E object) {
validate(object);
getListIterator().add(object);
}
@Override
public void set(final E object) {
validate(object);
getListIterator().set(object);
}
}
}