如何实现在JTable的某列标题栏上单击,则根据这列排序?绝对给分!!

http://java.sun.com/docs/books/tutorial/uiswing/components/table.htmltake a look at TableMap.java 、TableSorter.java and TableSorterDemo.java.

//看这个
package uemc.common.component;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.util.List;
import java.util.ArrayList;
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 revieved 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 a different 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>
*
* @author Philip Milne
* @author Brendon McLean
* @author Dan van Enckevort
* @author Parwinder Sekhon
*
*/ /*
*  This is a, long overdue, rewrite of a class of the same name that
*  first appeared in the swing table demos in 1997. This version was
*  last updated on: 25:2:2004
*/
public class TableSorter extends DefaultTableModel {
    protected DefaultTableModel tableModel;
    /*降序排列*/
    public static final int DESCENDING = -1;
    /*没有排序*/
    public static final int NOT_SORTED = 0;
    /*升序排列*/
    public static final int ASCENDING = 1;
    /**/
    private static Directive EMPTY_DIRECTIVE = new Directive(-1, NOT_SORTED);
    /*比较的接口*/
    public static final Comparator COMPARABLE_COMAPRATOR = new Comparator() {
        public int compare(Object o1, Object o2) {
            return ((Comparable) o1).compareTo(o2);
        }
    };
    /*比较的接口*/
    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(DefaultTableModel tableModel) {
        this();
        setTableModel(this.getChangedM(tableModel));
    }
    /**/
    public TableSorter(DefaultTableModel tableModel, JTableHeader tableHeader) {
        this();
        setTableHeader(tableHeader);
        setTableModel(this.getChangedM(tableModel));
    }
    /**/
    private void clearSortingState() {
        viewToModel = null;
        modelToView = null;
    }
    /**/
    public TableModel getTableModel() {
        return tableModel;
    }
    /**/
    public void setTableModel(DefaultTableModel 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();
        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
    /*得到行数值*/
    public int getRowCount() {
        return (tableModel == null) ? 0 : tableModel.getRowCount();
    }
    /*得到列数值*/
    public int getColumnCount() {
        return (tableModel == null) ? 0 : tableModel.getColumnCount();
    }
    /*获得某列的名字，而目前各列的名字保存在字符串数组columnNames中*/
    public String getColumnName(int column) {
        return tableModel.getColumnName(column);
    }
    /*判断每个单元格的类型*/
    public Class getColumnClass(int column) {
        return tableModel.getColumnClass(column);
    }
    /*将表格声明为可编辑的*/
    public boolean isCellEditable(int row, int column) {
        return tableModel.isCellEditable(modelIndex(row), column);
    }
    /*获得某行某列的数据，而数据保存在对象数组TableModel中*/
    public Object getValueAt(int row, int column) {
        return tableModel.getValueAt(modelIndex(row), column);
    }
    /*改变某个数据的值*/
    public void setValueAt(Object aValue, int row, int column) {
        tableModel.setValueAt(aValue, modelIndex(row), column);
    }    // 辅助类；    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()) {
                fireTableChanged(e);
                return;
            }

调试易

如何实现在JTable的某列标题栏上单击,则根据这列排序?绝对给分!!

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