/*
* $Id: SortIteratorFilter.java 651946 2008-04-27 13:41:38Z apetrelli $
*
* 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.struts2.util;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import com.opensymphony.xwork2.Action;
import com.opensymphony.xwork2.util.logging.LoggerFactory;
/**
* A bean that takes a source and comparator then attempt to sort the source
* utilizing the comparator. It is being used in SortIteratorTag.
*
* @see org.apache.struts2.views.jsp.iterator.SortIteratorTag
*/
public class SortIteratorFilter extends IteratorFilterSupport implements Iterator, Action {
Comparator comparator;
Iterator iterator;
List list;
// Attributes ----------------------------------------------------
Object source;
public void setComparator(Comparator aComparator) {
this.comparator = aComparator;
}
public List getList() {
return list;
}
// Public --------------------------------------------------------
public void setSource(Object anIterator) {
source = anIterator;
}
// Action implementation -----------------------------------------
public String execute() {
if (source == null) {
return ERROR;
} else {
try {
if (!MakeIterator.isIterable(source)) {
LoggerFactory.getLogger(SortIteratorFilter.class.getName()).warn("Cannot create SortIterator for source " + source);
return ERROR;
}
list = new ArrayList();
Iterator i = MakeIterator.convert(source);
while (i.hasNext()) {
list.add(i.next());
}
// Sort it
Collections.sort(list, comparator);
iterator = list.iterator();
return SUCCESS;
} catch (Exception e) {
LoggerFactory.getLogger(SortIteratorFilter.class.getName()).warn("Error creating sort iterator.", e);
return ERROR;
}
}
}
// Iterator implementation ---------------------------------------
public boolean hasNext() {
return (source == null) ? false : iterator.hasNext();
}
public Object next() {
return iterator.next();
}
public void remove() {
throw new UnsupportedOperationException("Remove is not supported in SortIteratorFilter.");
}
}
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