com.anrisoftware.prefdialog.miscswing.comboboxhistory.HistoryComboBoxModel.java Source code

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Here is the source code for com.anrisoftware.prefdialog.miscswing.comboboxhistory.HistoryComboBoxModel.java

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/*
 * Copyright 2013-2016 Erwin Mller <erwin.mueller@deventm.org>
 *
 * This file is part of prefdialog-misc-swing.
 *
 * prefdialog-misc-swing is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published by the
 * Free Software Foundation, either version 3 of the License, or (at your
 * option) any later version.
 *
 * prefdialog-misc-swing is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with prefdialog-misc-swing. If not, see <http://www.gnu.org/licenses/>.
 */
package com.anrisoftware.prefdialog.miscswing.comboboxhistory;

import static java.util.Collections.synchronizedSet;
import static org.apache.commons.lang3.StringUtils.isEmpty;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import javax.inject.Inject;
import javax.swing.MutableComboBoxModel;
import javax.swing.event.ListDataListener;

import com.google.inject.assistedinject.Assisted;

/**
 * Retains a history of added items in the model. In addition a set of default
 * items can be set that can not be removed from the model.
 *
 * @author Erwin Mueller, erwin.mueller@deventm.org
 * @since 1.0
 */
@SuppressWarnings({ "serial", "rawtypes", "unchecked" })
public class HistoryComboBoxModel implements MutableComboBoxModel, Serializable {

    /**
     * @see HistoryComboBoxModelFactory#create(MutableComboBoxModel, Set)
     */
    public static HistoryComboBoxModel decorate(MutableComboBoxModel model, Set defaultItems) {
        return ComboBoxHistoryModule.InstanceHolder.injector.getInstance(HistoryComboBoxModelFactory.class)
                .create(model, defaultItems);
    }

    private final MutableComboBoxModel model;

    private final Set<Object> defaultItems;

    private final Set<Object> items;

    private transient ItemDefaultFactory itemDefaultFactory;

    private int maximum;

    /**
     * @see HistoryComboBoxModelFactory#create(MutableComboBoxModel, Collection)
     */
    @Inject
    HistoryComboBoxModel(ItemDefaultFactory itemDefaultFactory, @Assisted MutableComboBoxModel model,
            @Assisted Collection defaultItems) {
        this.maximum = 5;
        this.model = model;
        this.itemDefaultFactory = itemDefaultFactory;
        Collection<Object> defaultItemsCollection = convertDefaultItems(defaultItems);
        this.defaultItems = new HashSet<Object>(defaultItemsCollection);
        this.items = synchronizedSet(fromModel(model));
        insertDefaultItems(defaultItemsCollection);
        setSelectedItem(model.getSelectedItem());
    }

    private Collection<Object> convertDefaultItems(Collection items) {
        List<Object> set = new ArrayList<Object>();
        for (Object item : items) {
            set.add(itemDefaultFactory.create(item));
        }
        return set;
    }

    private Set<Object> fromModel(MutableComboBoxModel model) {
        Set<Object> set = new HashSet<Object>(model.getSize());
        for (int i = 0; i < model.getSize(); i++) {
            set.add(model.getElementAt(i));
        }
        return set;
    }

    private void insertDefaultItems(Collection defaultItems) {
        items.addAll(defaultItems);
        for (Object item : defaultItems) {
            model.addElement(item);
        }
    }

    public void setMaximum(int maximum) {
        this.maximum = maximum;
        while (getCustomItemsSize() >= maximum) {
            removeElementAt(getLastItemIndex());
        }
    }

    public int getMaximum() {
        return maximum;
    }

    @Override
    public void addElement(Object item) {
        if (items.contains(itemDefaultFactory.create(item))) {
            setSelectedItem(item);
        } else {
            if (item instanceof String && isEmpty((String) item)) {
                return;
            }
            removeCustomElementFromEnd();
            model.insertElementAt(item, 0);
            items.add(item);
        }
    }

    private void removeCustomElementFromEnd() {
        if (getCustomItemsSize() == maximum) {
            Object item = getElementAt(getLastItemIndex());
            items.remove(item);
            model.removeElement(item);
        }
    }

    @Override
    public void removeElement(Object obj) {
        if (!defaultItems.contains(obj)) {
            model.removeElement(obj);
            items.remove(obj);
        }
    }

    private int getCustomItemsSize() {
        return getSize() - defaultItems.size();
    }

    private int getLastItemIndex() {
        int i = getSize() - 1;
        for (; i >= 0; i--) {
            if (!defaultItems.contains(getElementAt(i))) {
                break;
            }
        }
        return i;
    }

    @Override
    public int getSize() {
        return model.getSize();
    }

    @Override
    public void setSelectedItem(Object anItem) {
        model.setSelectedItem(anItem);
    }

    @Override
    public Object getElementAt(int index) {
        return model.getElementAt(index);
    }

    @Override
    public void addListDataListener(ListDataListener l) {
        model.addListDataListener(l);
    }

    @Override
    public void insertElementAt(Object item, int index) {
        Object idxitem = getElementAt(index);
        if (items.contains(idxitem)) {
            model.setSelectedItem(item);
        } else {
            if (item instanceof String && isEmpty((String) item)) {
                return;
            }
            model.insertElementAt(item, index);
            items.add(item);
        }
    }

    @Override
    public Object getSelectedItem() {
        return model.getSelectedItem();
    }

    @Override
    public void removeListDataListener(ListDataListener l) {
        model.removeListDataListener(l);
    }

    @Override
    public void removeElementAt(int index) {
        Object item = getElementAt(index);
        if (!defaultItems.contains(item)) {
            model.removeElement(item);
            items.remove(item);
        }
    }

}