Java tutorial
/* * Copyright (c) 1995, 2008, Oracle and/or its affiliates. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * - Neither the name of Oracle or the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ package components; 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; } 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 = h.columnAtPoint(e.getPoint()); 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; } } }