org.eclipse.nebula.widgets.nattable.extension.glazedlists/src/org/eclipse/nebula/widgets/nattable/extension/glazedlists/NatTableComparatorChooser.java

/*******************************************************************************
 * Copyright (c) 2012 Original authors and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Original authors and others - initial API and implementation
 ******************************************************************************/
package org.eclipse.nebula.widgets.nattable.extension.glazedlists;

import static org.eclipse.nebula.widgets.nattable.sort.SortDirectionEnum.ASC;
import static org.eclipse.nebula.widgets.nattable.sort.SortDirectionEnum.DESC;
import static org.eclipse.nebula.widgets.nattable.sort.SortDirectionEnum.NONE;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.nebula.widgets.nattable.sort.SortDirectionEnum;

import ca.odell.glazedlists.SortedList;
import ca.odell.glazedlists.gui.AbstractTableComparatorChooser;
import ca.odell.glazedlists.gui.TableFormat;

public class NatTableComparatorChooser<T> extends
        AbstractTableComparatorChooser<T> {

    public NatTableComparatorChooser(SortedList<T> sortedList,
            TableFormat<T> tableFormat) {
        super(sortedList, tableFormat);
    }

    void sort(int columnIndex, SortDirectionEnum sortDirection,
            boolean accumulate) {
        if (getComparatorsForColumn(columnIndex).isEmpty()) {
            return;
        }
        if (!accumulate) {
            clearComparator();
        }

        switch (sortDirection) {
            case NONE:
                removeSortingColumnIndex(columnIndex);
                break;
            case ASC:
                removeSortingColumnIndex(columnIndex);
                appendComparator(columnIndex, 0, false);
                break;
            case DESC:
                removeSortingColumnIndex(columnIndex);
                appendComparator(columnIndex, 0, true);
                break;
            default:
                break;
        }
    }

    private void removeSortingColumnIndex(int columnIndex) {
        // Save comparators
        List<ComparatorInfo> comparatorInfos = new ArrayList<ComparatorInfo>();
        for (int sortingColumnIndex : getSortingColumns()) {
            if (sortingColumnIndex != columnIndex) {
                boolean reverse = isColumnReverse(sortingColumnIndex);
                comparatorInfos.add(new ComparatorInfo(sortingColumnIndex,
                        reverse));
            }
        }

        clearComparator();

        // Rebuild comparators
        for (ComparatorInfo comparatorInfo : comparatorInfos) {
            appendComparator(comparatorInfo.columnIndex, 0,
                    comparatorInfo.isReverse);
        }
    }

    public boolean isColumnIndexSorted(int columnIndex) {
        return getSortingColumns().contains(Integer.valueOf(columnIndex));
    }

    public SortDirectionEnum getSortDirectionForColumnIndex(int columnIndex) {
        boolean sorted = getSortingColumns().contains(
                Integer.valueOf(columnIndex));
        if (!sorted) {
            return NONE;
        }
        return isColumnReverse(columnIndex) ? DESC : ASC;
    }

    /**
     * @return The order in which this column was clicked. Zero indexed. -1 if
     *         the column wasn't recently clicked.
     *
     *         Example: If column indexes 20, 10, 25 are clicked in that order,
     *         clickSequence(10) is 2.
     */
    int getClickSequence(int columnIndex) {
        return getSortingColumns().indexOf(Integer.valueOf(columnIndex));
    }

    /**
     * Helper object for tracking existing comparators
     */
    private class ComparatorInfo {
        final int columnIndex;
        final boolean isReverse;

        ComparatorInfo(int columnIndex, boolean reverse) {
            this.columnIndex = columnIndex;
            this.isReverse = reverse;
        }
    }

}