Application: gvSIG desktop

/**

 * gvSIG. Desktop Geographic Information System.

 *

 * Copyright (C) 2007-2013 gvSIG Association.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 3

 * of the License, or (at your option) any later version.

 *

 * This program 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 General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 * For any additional information, do not hesitate to contact us

 * at info AT gvsig.com, or visit our website www.gvsig.com.

 */

package org.gvsig.app.gui;

import java.awt.Color;

import java.awt.Component;

import java.awt.Graphics;

import java.awt.event.MouseAdapter;

import java.awt.event.MouseEvent;

import java.awt.event.MouseListener;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Comparator;

import java.util.HashMap;

import java.util.Iterator;

import java.util.List;

import java.util.Map;

import javax.swing.Icon;

import javax.swing.JLabel;

import javax.swing.JTable;

import javax.swing.event.TableModelEvent;

import javax.swing.event.TableModelListener;

import javax.swing.table.AbstractTableModel;

import javax.swing.table.JTableHeader;

import javax.swing.table.TableCellRenderer;

import javax.swing.table.TableColumnModel;

import javax.swing.table.TableModel;

/**

 * 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;

    }

    private int[] getModelToView() {

        if (modelToView == null) {

            int n = getViewToModel().length;

            modelToView = new int[n];

            for (int i = 0; i < n; i++) {

                modelToView[modelIndex(i)] = i;

            }

        }

        return modelToView;

    }

    // TableModel interface methods 

    public int getRowCount() {

        return (tableModel == null) ? 0 : tableModel.getRowCount();

    }

    public int getColumnCount() {

        return (tableModel == null) ? 0 : tableModel.getColumnCount();

    }

    public String getColumnName(int column) {

        return tableModel.getColumnName(column);

    }

    public Class getColumnClass(int column) {

        return tableModel.getColumnClass(column);

    }

    public boolean isCellEditable(int row, int column) {

        return tableModel.isCellEditable(modelIndex(row), column);

    }

    public Object getValueAt(int row, int column) {

        return tableModel.getValueAt(modelIndex(row), column);

    }

    public void setValueAt(Object aValue, int row, int column) {

        tableModel.setValueAt(aValue, modelIndex(row), column);

    }

    // Helper classes

    private class Row implements Comparable {

        private int modelIndex;

        public Row(int index) {

            this.modelIndex = index;

        }

        public int compareTo(Object o) {

            int row1 = modelIndex;

            int row2 = ((Row) o).modelIndex;

            for (Iterator it = sortingColumns.iterator(); it.hasNext();) {

                Directive directive = (Directive) it.next();

                int column = directive.column;

                Object o1 = tableModel.getValueAt(row1, column);

                Object o2 = tableModel.getValueAt(row2, column);

                int comparison = 0;

                // Define null less than everything, except null.

                if (o1 == null && o2 == null) {

                    comparison = 0;

                } else if (o1 == null) {

                    comparison = -1;

                } else if (o2 == null) {

                    comparison = 1;

                } else {

                    comparison = getComparator(column).compare(o1, o2);

                }

                if (comparison != 0) {

                    return directive.direction == DESCENDING ? -comparison : comparison;

                }

            }

            return 0;

        }

    }

    private class TableModelHandler implements TableModelListener {

        public void tableChanged(TableModelEvent e) {

            // If we're not sorting by anything, just pass the event along.             

            if (!isSorting()) {

                clearSortingState();

                fireTableChanged(e);

                return;

            }

            // If the table structure has changed, cancel the sorting; the             

            // sorting columns may have been either moved or deleted from             

            // the model. 

            if (e.getFirstRow() == TableModelEvent.HEADER_ROW) {

                cancelSorting();

                fireTableChanged(e);

                return;

            }

            // We can map a cell event through to the view without widening             

            // when the following conditions apply: 

            // 

            // a) all the changes are on one row (e.getFirstRow() == e.getLastRow()) and, 

            // b) all the changes are in one column (column != TableModelEvent.ALL_COLUMNS) and,

            // c) we are not sorting on that column (getSortingStatus(column) == NOT_SORTED) and, 

            // d) a reverse lookup will not trigger a sort (modelToView != null)

            //

            // Note: INSERT and DELETE events fail this test as they have column == ALL_COLUMNS.

            // 

            // The last check, for (modelToView != null) is to see if modelToView 

            // is already allocated. If we don't do this check; sorting can become 

            // a performance bottleneck for applications where cells  

            // change rapidly in different parts of the table. If cells 

            // change alternately in the sorting column and then outside of             

            // it this class can end up re-sorting on alternate cell updates - 

            // which can be a performance problem for large tables. The last 

            // clause avoids this problem. 

            int column = e.getColumn();

            if (e.getFirstRow() == e.getLastRow()

                    && column != TableModelEvent.ALL_COLUMNS

                    && getSortingStatus(column) == NOT_SORTED

                    && modelToView != null) {

                int viewIndex = getModelToView()[e.getFirstRow()];

                fireTableChanged(new TableModelEvent(TableSorter.this, 

                                                     viewIndex, viewIndex, 

                                                     column, e.getType()));

                return;

            }

            // Something has happened to the data that may have invalidated the row order. 

            clearSortingState();

            fireTableDataChanged();

            return;

        }

    }

    private class MouseHandler extends MouseAdapter {

        public void mouseClicked(MouseEvent e) {

            JTableHeader h = (JTableHeader) e.getSource();

            TableColumnModel columnModel = h.getColumnModel();

            int viewColumn = columnModel.getColumnIndexAtX(e.getX());

            int column = columnModel.getColumn(viewColumn).getModelIndex();

            if (column != -1) {

                int status = getSortingStatus(column);

                if (!e.isControlDown()) {

                    cancelSorting();

                }

                // Cycle the sorting states through {NOT_SORTED, ASCENDING, DESCENDING} or 

                // {NOT_SORTED, DESCENDING, ASCENDING} depending on whether shift is pressed. 

                status = status + (e.isShiftDown() ? -1 : 1);

                status = (status + 4) % 3 - 1; // signed mod, returning {-1, 0, 1}

                setSortingStatus(column, status);

            }

        }

    }

    private static class Arrow implements Icon {

        private boolean descending;

        private int size;

        private int priority;

        public Arrow(boolean descending, int size, int priority) {

            this.descending = descending;

            this.size = size;

            this.priority = priority;

        }

        public void paintIcon(Component c, Graphics g, int x, int y) {

            Color color = c == null ? Color.GRAY : c.getBackground();             

            // In a compound sort, make each succesive triangle 20% 

            // smaller than the previous one. 

            int dx = (int)(size/2*Math.pow(0.8, priority));

            int dy = descending ? dx : -dx;

            // Align icon (roughly) with font baseline. 

            y = y + 5*size/6 + (descending ? -dy : 0);

            int shift = descending ? 1 : -1;

            g.translate(x, y);

            // Right diagonal. 

            g.setColor(color.darker());

            g.drawLine(dx / 2, dy, 0, 0);

            g.drawLine(dx / 2, dy + shift, 0, shift);

            // Left diagonal. 

            g.setColor(color.brighter());

            g.drawLine(dx / 2, dy, dx, 0);

            g.drawLine(dx / 2, dy + shift, dx, shift);

            // Horizontal line. 

            if (descending) {

                g.setColor(color.darker().darker());

            } else {

                g.setColor(color.brighter().brighter());

            }

            g.drawLine(dx, 0, 0, 0);

            g.setColor(color);

            g.translate(-x, -y);

        }

        public int getIconWidth() {

            return size;

        }

        public int getIconHeight() {

            return size;

        }

    }

    private class SortableHeaderRenderer implements TableCellRenderer {

        private TableCellRenderer tableCellRenderer;

        public SortableHeaderRenderer(TableCellRenderer tableCellRenderer) {

            this.tableCellRenderer = tableCellRenderer;

        }

        public Component getTableCellRendererComponent(JTable table, 

                                                       Object value,

                                                       boolean isSelected, 

                                                       boolean hasFocus,

                                                       int row, 

                                                       int column) {

            Component c = tableCellRenderer.getTableCellRendererComponent(table, 

                    value, isSelected, hasFocus, row, column);

            if (c instanceof JLabel) {

                JLabel l = (JLabel) c;

                l.setHorizontalTextPosition(JLabel.LEFT);

                int modelColumn = table.convertColumnIndexToModel(column);

                l.setIcon(getHeaderRendererIcon(modelColumn, l.getFont().getSize()));

            }

            return c;

        }

    }

    private static class Directive {

        private int column;

        private int direction;

        public Directive(int column, int direction) {

            this.column = column;

            this.direction = direction;

        }

    }

}