DepartmentGrouper.java

/**
 * Copyright 1999-2009 The Pegadi Team
 *
 * Licensed 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.pegadi.articlelist;

import org.pegadi.model.Article;
import org.pegadi.model.Section;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.TreeSet;

public class DepartmentGrouper implements Grouper {
    private String name;

    private final Logger log = LoggerFactory.getLogger(getClass());

    public boolean equals(Object obj) {
        return obj instanceof DepartmentGrouper;
    }

    public DepartmentGrouper(String name) {
        this.name = name;
    }

    public DepartmentGrouper() {
        this("Section");
    }

    public String toString() {
        return this.getName();
    }

    public String getName() {
        return name;
    }

    public GroupedArticles group(Article[] articles, Comparator comparator) {

        // first, lets find all departments in the incoming set.
        // we use TreeSet, since this class doesn't permit duplicates,
        // and also automagically sorts the objects for us, for the given comparator.

        ArrayList[] tempArrayListOut;
        String[] tempHeaders;
        ArticleSum[] tempSums;
        TreeSet actualSortObjects = new TreeSet();
        boolean hasNulls = false;
        GroupedArticles groupedArticles = new GroupedArticles();
        ArrayList groupIndexes;

        for (Article article1 : articles) {
            if (article1 != null) {
                if (article1.getSection() != null)
                    actualSortObjects.add(article1.getSection());
                else
                    hasNulls = true;
            }
        }

        // then, we convert the TreeSet to a Vector
        // so that we get a sorted and indexed list of departments.
        // if there are articles without Section, create a "empty"
        // folder at the end.

        groupIndexes = new ArrayList(actualSortObjects);
        if (hasNulls)
            groupIndexes.add(new Section(0, "No department", ""));

        // initalize the ArrayLists

        int numberOfGroups = groupIndexes.size();
        groupedArticles.setNumberOfGroups(numberOfGroups);
        tempArrayListOut = new ArrayList[numberOfGroups];
        for (int i = 0; i < tempArrayListOut.length; i++)
            tempArrayListOut[i] = new ArrayList();

        // now, iterate over all the articles, and duplicating
        // them into the correct ArrayList

        for (Article article : articles) {
            if (article != null) {
                Section tempSection = article.getSection();
                int tempIndex = groupIndexes.indexOf(tempSection);
                if (tempIndex == -1) // no such department, put it in "empt dep."
                    tempArrayListOut[numberOfGroups - 1].add(article);
                else
                    tempArrayListOut[tempIndex].add(article);
            }
        }

        // Sort all the arraylists
        for (ArrayList aTempArrayListOut : tempArrayListOut) Collections.sort(aTempArrayListOut, comparator);

        // update the group headers

        tempHeaders = new String[numberOfGroups];
        for (int i = 0; i < numberOfGroups; i++) {
            Section tempSection2 = (Section) groupIndexes.get(i);
            tempHeaders[i] = tempSection2.getName();
        }
        groupedArticles.setGroupHeaders(tempHeaders);

        // update the group sums
        tempSums = new ArticleSum[numberOfGroups];
        for (int i = 0; i < numberOfGroups; i++) {
            tempSums[i] = new ArticleSum();
            for (Object o : tempArrayListOut[i]) {
                Article tempArticle = (Article) o;
                int tempInt = tempArticle.getWantedNumberOfCharacters();
                tempSums[i].add(tempInt);

            }
        }

        // update, and return the results.
        groupedArticles.setGroupedArticles(tempArrayListOut);
        groupedArticles.setGroupHeaders(tempHeaders);
        groupedArticles.setGroupSums(tempSums);
        return groupedArticles;
    }
}