tablesorter.java

JAVA数据库编程实例源码及其一些Java基本介绍

package testdatabase;

import java.util.*;

import javax.swing.table.TableModel;
import javax.swing.event.TableModelEvent;
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.TableColumn;
import javax.swing.table.TableColumnModel;

/**
 * Title:        测试数据库
 * Description:  Java语言演示程序：测试数据库，用于北京师范大学计算机系Java课程教学示范。
 * Copyright:    Copyright (c) 2002
 * Company:      北京师范大学计算机系
 * @author 孙一林
 * @version 1.0
 */

public class TableSorter extends TableMap{
    int             indexes[];
    Vector          sortingColumns = new Vector();
    boolean         ascending = true;
    int compares;

    public TableSorter(){
        indexes = new int[0];
    }

    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;

        Object o1 = data.getValueAt(row1, column);
        Object o2 = data.getValueAt(row2, column);

        if (o1 == null && o2 == null) {
            return 0;
        }
        else if (o1 == null) {
            return -1;
        }
        else if (o2 == null) {
            return 1;
        }

        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)
                    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();

        indexes = new int[rowCount];

        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()) {
            System.err.println("Sorter not informed of a change in model.");
        }
    }

    public void  sort(Object sender) {
        checkModel();

        compares = 0;
        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);
                }
            }
        }
    }

    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;

        if (high - low >= 4 && compare(from[middle-1], from[middle]) <= 0) {
            for (int i = low; i < high; i++) {
                to[i] = from[i];
            }
            return;
        }

        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;
    }

    public Object getValueAt(int aRow, int aColumn) {
        checkModel();
        return model.getValueAt(indexes[aRow], aColumn);
    }

    public void setValueAt(Object aValue, int aRow, int aColumn){
        checkModel();
        model.setValueAt(aValue, indexes[aRow], aColumn);
    }

    public void sortByColumn(int column) {
        sortByColumn(column, true);
    }

    public void sortByColumn(int column, boolean ascending) {
        this.ascending = ascending;
        sortingColumns.removeAllElements();
        sortingColumns.addElement(new Integer(column));
        sort(this);
        super.tableChanged(new TableModelEvent(this));
    }

    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);
    }
}