/**
* 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
* @modified Keita Fujii
*/
package jdumper.ui;
import java.util.*;
import javax.swing.table.TableModel;
import javax.swing.event.TableModelEvent;
// 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 javax.swing.JTable;
import javax.swing.table.JTableHeader;
import javax.swing.table.TableColumnModel;
public class TableSorter extends TableMap {
int indexes[];
Vector sortingColumns = new Vector();
boolean ascending = true;
int compares;
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;
}
if(o1.getClass() != o2.getClass())
return -1;
Class type=o1.getClass();
/*
* 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();
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 {
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();
super.tableChanged(e);
}
public void checkModel() {
if (indexes.length != model.getRowCount()) {
reallocateIndexes();
//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 mus
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