TableSorter.java revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
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*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
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/*
* Copyright 2000 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*
* ident "%Z%%M% %I% %E% SMI"
*/
package com.sun.dhcpmgr.ui;
/*
* @(#)TableSorter.java 1.5 97/12/17
*/
/**
* A sorter for TableModels. The sorter has a model (conforming to TableModel)
* and itself implements TableModel. TableSorter does not store or copy
* the data in the TableModel, instead it maintains an array of
* integers which it keeps the same size as the number of rows in its
* model. When the model changes it notifies the sorter that something
* has changed eg. "rowsAdded" so that its internal array of integers
* can be reallocated. As requests are made of the sorter (like
* getValueAt(row, col) it redirects them to its model via the mapping
* array. That way the TableSorter appears to hold another copy of the table
* with the rows in a different order. The sorting algorthm used is stable
* which means that it does not move around rows when its comparison
* function returns 0 to denote that they are equivalent.
*
* @version 1.5 12/17/97
* @author Philip Milne
*/
import java.util.*;
import javax.swing.table.TableModel;
import javax.swing.event.TableModelEvent;
import com.sun.dhcpmgr.data.IPAddress;
// Imports for picking up mouse events from the JTable.
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.InputEvent;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JTable;
import javax.swing.table.JTableHeader;
import javax.swing.table.TableColumn;
import javax.swing.table.TableColumnModel;
public class TableSorter extends TableMap
{
int indexes[] = new int[0];
Vector sortingColumns = new Vector();
boolean ascending = true;
int compares;
Vector listeners = new Vector();
public TableSorter() {
indexes = new int[0]; // For consistency.
}
public TableSorter(TableModel model) {
setModel(model);
}
public void setModel(TableModel model) {
super.setModel(model);
reallocateIndexes();
}
public int compareRowsByColumn(int row1, int row2, int column) {
Class type = model.getColumnClass(column);
TableModel data = model;
// Check for nulls
Object o1 = data.getValueAt(row1, column);
Object o2 = data.getValueAt(row2, column);
// If both values are null return 0
if (o1 == null && o2 == null) {
return 0;
} else if (o1 == null) { // Define null less than everything.
return -1;
} else if (o2 == null) {
return 1;
}
/*
* We copy all returned values from the getValue call in case
* an optimised model is reusing one object to return many values.
* The Number subclasses in the JDK are immutable and so will not be
* used in this way but other subclasses of Number might want to do
* this to save space and avoid unnecessary heap allocation.
*/
if (type.getSuperclass() == java.lang.Number.class) {
Number n1 = (Number)data.getValueAt(row1, column);
double d1 = n1.doubleValue();
Number n2 = (Number)data.getValueAt(row2, column);
double d2 = n2.doubleValue();
if (d1 < d2)
return -1;
else if (d1 > d2)
return 1;
else
return 0;
} else if (type == java.util.Date.class) {
Date d1 = (Date)data.getValueAt(row1, column);
long n1 = d1.getTime();
Date d2 = (Date)data.getValueAt(row2, column);
long n2 = d2.getTime();
// Handle negatives specially
if (n1 < 0) {
return 1;
} else if (n2 < 0) {
return -1;
}
if (n1 < n2)
return -1;
else if (n1 > n2)
return 1;
else
return 0;
} else if (type == String.class) {
String s1 = (String)data.getValueAt(row1, column);
String s2 = (String)data.getValueAt(row2, column);
int result = s1.compareTo(s2);
if (result < 0)
return -1;
else if (result > 0)
return 1;
else return 0;
} else if (type == Boolean.class) {
Boolean bool1 = (Boolean)data.getValueAt(row1, column);
boolean b1 = bool1.booleanValue();
Boolean bool2 = (Boolean)data.getValueAt(row2, column);
boolean b2 = bool2.booleanValue();
if (b1 == b2)
return 0;
else if (b1) // Define false < true
return 1;
else
return -1;
} else if (type == IPAddress.class) {
IPAddress addr1 = (IPAddress)data.getValueAt(row1, column);
IPAddress addr2 = (IPAddress)data.getValueAt(row2, column);
byte [] a1 = addr1.getAddress();
byte [] a2 = addr2.getAddress();
int c1, c2;
for (int i = 0; i < a1.length; ++i) {
/*
* Promote and mask because bytes are signed and 128-255
* will be done wrong
*/
c1 = a1[i] & 0xff;
c2 = a2[i] & 0xff;
if (c1 < c2) {
return -1;
} else if (c1 > c2) {
return 1;
}
}
return 0;
} else {
Object v1 = data.getValueAt(row1, column);
String s1 = v1.toString();
Object v2 = data.getValueAt(row2, column);
String s2 = v2.toString();
int result = s1.compareTo(s2);
if (result < 0)
return -1;
else if (result > 0)
return 1;
else return 0;
}
}
public int compare(int row1, int row2) {
compares++;
for (int level = 0; level < sortingColumns.size(); level++) {
Integer column = (Integer)sortingColumns.elementAt(level);
int result = compareRowsByColumn(row1, row2, column.intValue());
if (result != 0)
return ascending ? result : -result;
}
return 0;
}
public void reallocateIndexes() {
int rowCount = model.getRowCount();
// Set up a new array of indexes with the right number of elements
// for the new data model.
indexes = new int[rowCount];
// Initialise with the identity mapping.
for (int row = 0; row < rowCount; row++)
indexes[row] = row;
}
public void tableChanged(TableModelEvent e) {
// System.out.println("Sorter: tableChanged");
reallocateIndexes();
sort(this);
super.tableChanged(e);
}
public void checkModel() {
if (indexes.length != model.getRowCount()) {
System.err.println("Sorter not informed of a change in model.");
}
}
public void sort(Object sender) {
checkModel();
compares = 0;
// n2sort();
// qsort(0, indexes.length-1);
shuttlesort((int[])indexes.clone(), indexes, 0, indexes.length);
// System.out.println("Compares: "+compares);
}
public void n2sort() {
for (int i = 0; i < getRowCount(); i++) {
for (int j = i+1; j < getRowCount(); j++) {
if (compare(indexes[i], indexes[j]) == -1) {
swap(i, j);
}
}
}
}
/*
* This is a home-grown implementation which we have not had time
* to research - it may perform poorly in some circumstances. It
* requires twice the space of an in-place algorithm and makes
* NlogN assigments shuttling the values between the two
* arrays. The number of compares appears to vary between N-1 and
* NlogN depending on the initial order but the main reason for
* using it here is that, unlike qsort, it is stable.
*/
public void shuttlesort(int from[], int to[], int low, int high) {
if (high - low < 2) {
return;
}
int middle = (low + high)/2;
shuttlesort(to, from, low, middle);
shuttlesort(to, from, middle, high);
int p = low;
int q = middle;
/*
* This is an optional short-cut; at each recursive call,
* check to see if the elements in this subset are already
* ordered. If so, no further comparisons are needed; the
* sub-array can just be copied. The array must be copied rather
* than assigned otherwise sister calls in the recursion might
* get out of sinc. When the number of elements is three they
* are partitioned so that the first set, [low, mid), has one
* element and and the second, [mid, high), has two. We skip the
* optimisation when the number of elements is three or less as
* the first compare in the normal merge will produce the same
* sequence of steps. This optimisation seems to be worthwhile
* for partially ordered lists but some analysis is needed to
* find out how the performance drops to Nlog(N) as the initial
* order diminishes - it may drop very quickly.
*/
if (high - low >= 4 && compare(from[middle-1], from[middle]) <= 0) {
for (int i = low; i < high; i++) {
to[i] = from[i];
}
return;
}
// A normal merge.
for (int i = low; i < high; i++) {
if (q >= high || (p < middle && compare(from[p], from[q]) <= 0)) {
to[i] = from[p++];
} else {
to[i] = from[q++];
}
}
}
public void swap(int i, int j) {
int tmp = indexes[i];
indexes[i] = indexes[j];
indexes[j] = tmp;
}
/*
* The mapping only affects the contents of the data rows.
* Pass all requests to these rows through the mapping array: "indexes".
*/
public Object getValueAt(int aRow, int aColumn)
{
checkModel();
return model.getValueAt(indexes[aRow], aColumn);
}
public int mapRowAt(int aRow) {
checkModel();
if (aRow < indexes.length) {
return indexes[aRow];
} else {
return -1;
}
}
public void setValueAt(Object aValue, int aRow, int aColumn) {
checkModel();
model.setValueAt(aValue, indexes[aRow], aColumn);
}
public void sortByColumn(int column) {
// Re-sort on this column, but don't change sort order
sortByColumn(column, this.ascending);
}
public void sortByColumn(int column, boolean ascending) {
this.ascending = ascending;
sortingColumns.removeAllElements();
sortingColumns.addElement(new Integer(column));
sort(this);
super.tableChanged(new TableModelEvent(this));
fireActionPerformed();
}
/*
* There is no-where else to put this.
* Add a mouse listener to the Table to trigger a table sort
* when a column heading is clicked in the JTable.
*/
public void addMouseListenerToHeaderInTable(JTable table) {
final TableSorter sorter = this;
final JTable tableView = table;
tableView.setColumnSelectionAllowed(false);
MouseAdapter listMouseListener = new MouseAdapter() {
public void mouseClicked(MouseEvent e) {
TableColumnModel columnModel = tableView.getColumnModel();
int viewColumn = columnModel.getColumnIndexAtX(e.getX());
int column = tableView.convertColumnIndexToModel(viewColumn);
if (e.getClickCount() == 1 && column != -1) {
// System.out.println("Sorting ...");
int shiftPressed = e.getModifiers()&InputEvent.SHIFT_MASK;
boolean ascending = (shiftPressed == 0);
sorter.sortByColumn(column, ascending);
}
}
};
JTableHeader th = tableView.getTableHeader();
th.addMouseListener(listMouseListener);
}
// Allow others to be notified when re-sorting is done
public void addActionListener(ActionListener l) {
listeners.addElement(l);
}
// Take me off the notify list
public void removeActionListener(ActionListener l) {
listeners.removeElement(l);
}
/*
* Notify listeners of sort events; we just use ActionEvent as it's a
* good all-purpose event
*/
protected void fireActionPerformed() {
ActionEvent e = new ActionEvent(this, ActionEvent.ACTION_PERFORMED,
sortingColumns.firstElement().toString());
Enumeration en = listeners.elements();
while (en.hasMoreElements()) {
ActionListener l = (ActionListener)en.nextElement();
l.actionPerformed(e);
}
}
}