tablesorter.java

Semantic Web Ontology Editor

package org.mindswap.swoop.explore;

import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.util.List;

import javax.swing.*;
import javax.swing.event.TableModelEvent;
import javax.swing.event.TableModelListener;
import javax.swing.table.*;

/**
 * TableSorter is a decorator for TableModels; adding sorting
 * functionality to a supplied TableModel. TableSorter does
 * not store or copy the data in its TableModel; instead it maintains
 * a map from the row indexes of the view to the row indexes of the
 * model. As requests are made of the sorter (like getValueAt(row, col))
 * they are passed to the underlying model after the row numbers
 * have been translated via the internal mapping array. This way,
 * the TableSorter appears to hold another copy of the table
 * with the rows in a different order.
 * <p/>
 * TableSorter registers itself as a listener to the underlying model,
 * just as the JTable itself would. Events recieved from the model
 * are examined, sometimes manipulated (typically widened), and then
 * passed on to the TableSorter's listeners (typically the JTable).
 * If a change to the model has invalidated the order of TableSorter's
 * rows, a note of this is made and the sorter will resort the
 * rows the next time a value is requested.
 * <p/>
 * When the tableHeader property is set, either by using the
 * setTableHeader() method or the two argument constructor, the
 * table header may be used as a complete UI for TableSorter.
 * The default renderer of the tableHeader is decorated with a renderer
 * that indicates the sorting status of each column. In addition,
 * a mouse listener is installed with the following behavior:
 * <ul>
 * <li>
 * Mouse-click: Clears the sorting status of all other columns
 * and advances the sorting status of that column through three
 * values: {NOT_SORTED, ASCENDING, DESCENDING} (then back to
 * NOT_SORTED again).
 * <li>
 * SHIFT-mouse-click: Clears the sorting status of all other columns
 * and cycles the sorting status of the column through the same
 * three values, in the opposite order: {NOT_SORTED, DESCENDING, ASCENDING}.
 * <li>
 * CONTROL-mouse-click and CONTROL-SHIFT-mouse-click: as above except
 * that the changes to the column do not cancel the statuses of columns
 * that are already sorting - giving a way to initiate a compound
 * sort.
 * </ul>
 * <p/>
 * This is a long overdue rewrite of a class of the same name that
 * first appeared in the swing table demos in 1997.
 * 
 * @author Philip Milne
 * @author Brendon McLean 
 * @author Dan van Enckevort
 * @author Parwinder Sekhon
 * @version 2.0 02/27/04
 */

public class TableSorter extends AbstractTableModel {
    protected TableModel tableModel;

    public static final int DESCENDING = -1;
    public static final int NOT_SORTED = 0;
    public static final int ASCENDING = 1;

    private static Directive EMPTY_DIRECTIVE = new Directive(-1, NOT_SORTED);

    public static final Comparator COMPARABLE_COMAPRATOR = new Comparator() {
        public int compare(Object o1, Object o2) {
            return ((Comparable) o1).compareTo(o2);
        }
    };
    public static final Comparator LEXICAL_COMPARATOR = new Comparator() {
        public int compare(Object o1, Object o2) {
            return o1.toString().compareTo(o2.toString());
        }
    };

    private Row[] viewToModel;
    private int[] modelToView;

    private JTableHeader tableHeader;
    private MouseListener mouseListener;
    private TableModelListener tableModelListener;
    private Map columnComparators = new HashMap();
    private List sortingColumns = new ArrayList();

    public TableSorter() 
    {
        this.mouseListener = new MouseHandler();
        this.tableModelListener = new TableModelHandler();
    }

    public TableSorter(TableModel tableModel) 
    {    	
        this();
        setTableModel(tableModel);
    }

    public TableSorter(TableModel tableModel, JTableHeader tableHeader) {
        this();
        setTableHeader(tableHeader);
        setTableModel(tableModel);
    }

    private void clearSortingState() {
        viewToModel = null;
        modelToView = null;
    }

    public TableModel getTableModel() {
        return tableModel;
    }

    public void setTableModel(TableModel tableModel) {
        if (this.tableModel != null) {
            this.tableModel.removeTableModelListener(tableModelListener);
        }

        this.tableModel = tableModel;
        if (this.tableModel != null) {
            this.tableModel.addTableModelListener(tableModelListener);
        }

        clearSortingState();
        fireTableStructureChanged();
    }

    public JTableHeader getTableHeader() {
        return tableHeader;
    }

    public void setTableHeader(JTableHeader tableHeader) {
        if (this.tableHeader != null) {
            this.tableHeader.removeMouseListener(mouseListener);
            TableCellRenderer defaultRenderer = this.tableHeader.getDefaultRenderer();
            if (defaultRenderer instanceof SortableHeaderRenderer) {
                this.tableHeader.setDefaultRenderer(((SortableHeaderRenderer) defaultRenderer).tableCellRenderer);
            }
        }
        this.tableHeader = tableHeader;
        if (this.tableHeader != null) {
            this.tableHeader.addMouseListener(mouseListener);
            this.tableHeader.setDefaultRenderer(
                    new SortableHeaderRenderer(this.tableHeader.getDefaultRenderer()));
        }
    }

    public boolean isSorting() {
        return sortingColumns.size() != 0;
    }

    private Directive getDirective(int column) {
        for (int i = 0; i < sortingColumns.size(); i++) {
            Directive directive = (Directive)sortingColumns.get(i);
            if (directive.column == column) {
                return directive;
            }
        }
        return EMPTY_DIRECTIVE;
    }

    public int getSortingStatus(int column) {
        return getDirective(column).direction;
    }

    private void sortingStatusChanged() {
        clearSortingState();
        fireTableDataChanged();
        if (tableHeader != null) {
            tableHeader.repaint();
        }
    }

    public void setSortingStatus(int column, int status) {
        Directive directive = getDirective(column);
        if (directive != EMPTY_DIRECTIVE) {
            sortingColumns.remove(directive);
        }
        if (status != NOT_SORTED) {
            sortingColumns.add(new Directive(column, status));
        }
        sortingStatusChanged();
    }

    protected Icon getHeaderRendererIcon(int column, int size) {
        Directive directive = getDirective(column);
        if (directive == EMPTY_DIRECTIVE) {
            return null;
        }
        return new Arrow(directive.direction == DESCENDING, size, sortingColumns.indexOf(directive));
    }

    private void cancelSorting() {
        sortingColumns.clear();
        sortingStatusChanged();
    }

    public void setColumnComparator(Class type, Comparator comparator) {
        if (comparator == null) {
            columnComparators.remove(type);
        } else {
            columnComparators.put(type, comparator);
        }
    }

    protected Comparator getComparator(int column) {
        Class columnType = tableModel.getColumnClass(column);
        Comparator comparator = (Comparator) columnComparators.get(columnType);
        if (comparator != null) {
            return comparator;
        }
        if (Comparable.class.isAssignableFrom(columnType)) {
            return COMPARABLE_COMAPRATOR;
        }
        return LEXICAL_COMPARATOR;
    }

    private Row[] getViewToModel() {
        if (viewToModel == null) {
            int tableModelRowCount = tableModel.getRowCount();
            viewToModel = new Row[tableModelRowCount];
            for (int row = 0; row < tableModelRowCount; row++) {
                viewToModel[row] = new Row(row);
            }

            if (isSorting()) {
                Arrays.sort(viewToModel);
            }
        }
        return viewToModel;
    }

    public int modelIndex(int viewIndex) {
        return getViewToModel()[viewIndex].modelIndex;
    }