Java Swing JTable開(kāi)啟排序功能只需一個(gè)調(diào)用：

JTable table = new JTable();
table.setAutoCreateRowSorter(true);

但這個(gè)排序功能只支持單列排序值依，而多列排序需要自己實(shí)現(xiàn)奋渔。

本文內(nèi)容是使用sorter和renderer實(shí)現(xiàn)點(diǎn)擊表頭進(jìn)行多列排序，第一次點(diǎn)擊的列作為主排序列兽叮，后點(diǎn)擊的列作為次排序列芬骄。建議在開(kāi)始閱讀本文前可以看看官方教程《How to Use Tables》，對(duì)JTable的sorter和renderer有個(gè)概念鹦聪。

分析

TableRowSorter對(duì)象已經(jīng)提供了多列排序的功能：

TableRowSorter<TableModel> sorter 
    = new TableRowSorter<TableModel>(table.getModel());
table.setRowSorter(sorter);

List <RowSorter.SortKey> sortKeys 
    = new ArrayList<RowSorter.SortKey>();
sortKeys.add(new RowSorter.SortKey(1, SortOrder.ASCENDING));
sortKeys.add(new RowSorter.SortKey(0, SortOrder.ASCENDING));
sorter.setSortKeys(sortKeys);  // 執(zhí)行排序

上面是把第1列作為主排序列升序排序账阻，把第0列作為次排序列降序排序。

表格的表頭由JTableHeader對(duì)象維護(hù)泽本，該對(duì)象里維護(hù)著BaseTableHeaderUI對(duì)象淘太，這個(gè)對(duì)象里設(shè)置了mouseInputListener監(jiān)聽(tīng)器進(jìn)行監(jiān)聽(tīng)，當(dāng)點(diǎn)擊表頭后就通知該監(jiān)聽(tīng)器調(diào)用sorter.toggleSortOrder方法進(jìn)行排序规丽。所以我們需要繼承TableRowSorter類重寫(xiě)toggleSortOrder方法實(shí)現(xiàn)自己的排序邏輯蒲牧。

另一個(gè)要考慮的就是表頭的上下箭頭顯示，用于顯示該列是升序或降序排序赌莺。

JTableHeader對(duì)象默認(rèn)使用DefaultTableCellHeaderRenderer對(duì)象作為表頭Renderer冰抢，Renderer的getTableCellRendererComponent方法里設(shè)置上下箭頭圖標(biāo)并返回用于顯示表頭單元格的組件，而該方法里調(diào)用的getColumnSortOrder方法只會(huì)返回主排序列的排序順序艘狭，通過(guò)該方法的返回值只能顯示主排序列的箭頭挎扰。所以需要重寫(xiě)DefaultTableCellHeaderRenderer對(duì)象的相關(guān)方法實(shí)現(xiàn)讓多個(gè)列顯示上下箭頭，再通過(guò)JTable的getTableHeader().setDefaultRenderer(TableCellRenderer defaultRenderer)方法指定我們的表頭Renderer）

實(shí)現(xiàn)

通過(guò)上面的分析巢音，我們通過(guò)編寫(xiě)自己的sorter和renderer實(shí)現(xiàn)多列排序遵倦。
代碼與相關(guān)注釋（在JDK8下測(cè)試運(yùn)行）：
TableSortDemo.java：

package com.test.sort;

import javax.swing.*;
import javax.swing.table.*;
import java.awt.*;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

public class TableSortDemo extends JPanel {
    public TableSortDemo() {
        super(new GridLayout(1, 0));

        JTable table = new JTable(new AbstractTableModel() {
            private String[] columnNames = {"First Name",
                    "Last Name",
                    "Sport",
                    "# of Years",
                    "Vegetarian"};
            private Object[][] data = {
                    {"Kathy", "Smith",
                            "Snowboarding", new Integer(10), new Boolean(false)},
                    {"John", "Doe",
                            "Rowing", new Integer(3), new Boolean(true)},
                    {"Sue", "White",
                            "Knitting", new Integer(2), new Boolean(false)},
                    {"Kathy", "White",
                            "Speed reading", new Integer(20), new Boolean(true)},
                    {"Joe", "Brown",
                            "Pool", new Integer(10), new Boolean(true)}
            };

            public int getColumnCount() {
                return columnNames.length;
            }

            public int getRowCount() {
                return data.length;
            }

            public String getColumnName(int col) {
                return columnNames[col];
            }

            public Object getValueAt(int row, int col) {
                return data[row][col];
            }

            public Class getColumnClass(int c) {
                return getValueAt(0, c).getClass();
            }
        });
        table.setPreferredScrollableViewportSize(new Dimension(500, 70));
        table.setFillsViewportHeight(true);

        // 設(shè)置自己的Sorter
        MultiColumnTableRowSorter<TableModel> tableRowSorter = new MultiColumnTableRowSorter<>(table.getModel());
        table.setRowSorter(tableRowSorter);

        // 設(shè)置自己的表頭Render
        table.getTableHeader().setDefaultRenderer(new MutilColumnTableCellHeaderRenderer());

        // 設(shè)置監(jiān)聽(tīng)，輸出排序列調(diào)試信息
        table.getTableHeader().addMouseListener(new MouseAdapter() {
            @Override
            public void mouseClicked(MouseEvent e) {
                if (e.getClickCount() % 2 == 1 && SwingUtilities.isLeftMouseButton(e)) {
                    JTableHeader header = table.getTableHeader();
                    RowSorter sorter;
                    if ((sorter = table.getRowSorter()) != null) {
                        int columnIndex = header.columnAtPoint(e.getPoint());
                        if (columnIndex != -1) {
                            for (Object key: sorter.getSortKeys()) {
                                RowSorter.SortKey sortKey = (RowSorter.SortKey)key;
                                System.out.print(sortKey.getColumn() + ":" + sortKey.getSortOrder().name() + "  |  ");
                            }
                            System.out.println("\n--------------");
                        }
                    }
                }
            }
        });

        JScrollPane scrollPane = new JScrollPane(table);
        add(scrollPane);
    }

    private static void createAndShowGUI() {
        JFrame frame = new JFrame("TableSortDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        TableSortDemo newContentPane = new TableSortDemo();
        newContentPane.setOpaque(true); //content panes must be opaque
        frame.setContentPane(newContentPane);

        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
}

MultiColumnTableRowSorter.java：

package com.test.sort;

import javax.swing.*;
import javax.swing.table.TableModel;
import javax.swing.table.TableRowSorter;
import java.util.ArrayList;
import java.util.List;

public class MultiColumnTableRowSorter<M extends TableModel> extends TableRowSorter<M> {
    public MultiColumnTableRowSorter(M model) {
        super(model);
    }

    @Override
    public void toggleSortOrder(int column) {
        checkColumn(column);
        if (isSortable(column)) {
            List<SortKey> keys = new ArrayList<SortKey>(getSortKeys());
            SortKey sortKey;
            int sortIndex;
            for (sortIndex = keys.size() - 1; sortIndex >= 0; sortIndex--) {
                if (keys.get(sortIndex).getColumn() == column) {
                    break;
                }
            }
            if (sortIndex == -1) {
                // Key doesn't exist
                sortKey = new SortKey(column, SortOrder.ASCENDING);
                keys.add(sortKey);
            }
            else {
                SortKey key = keys.get(sortIndex);
                if(key.getSortOrder() == SortOrder.ASCENDING){
                    key = new SortKey(key.getColumn(), SortOrder.DESCENDING);
                    keys.set(sortIndex, key);
                }
                else if(key.getSortOrder() == SortOrder.DESCENDING){
                    keys.remove(sortIndex);
                }
            }

            if (keys.size() > getMaxSortKeys()) {
                keys = keys.subList(getMaxSortKeys(), keys.size());
            }
            setSortKeys(keys);
        }
    }

    private void checkColumn(int column) {
        if (column < 0 || column >= getModelWrapper().getColumnCount()) {
            throw new IndexOutOfBoundsException(
                    "column beyond range of TableModel");
        }
    }
}

MutilColumnTableCellHeaderRenderer.java（因?yàn)?code>sun.swing.table.DefaultTableCellRenderer的getColumnSortOrder方法是靜態(tài)方法不能被覆蓋官撼，所以直接復(fù)制DefaultTableCellRenderer類的代碼修改getColumnSortOrder方法）:

package com.test.sort;

import sun.swing.DefaultLookup;

import javax.swing.*;
import javax.swing.border.Border;
import javax.swing.plaf.UIResource;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.JTableHeader;
import java.awt.*;
import java.io.Serializable;
import java.util.List;


public class MutilColumnTableCellHeaderRenderer extends DefaultTableCellRenderer implements UIResource {
    private boolean horizontalTextPositionSet;
    private Icon sortArrow;
    private MutilColumnTableCellHeaderRenderer.EmptyIcon emptyIcon = new MutilColumnTableCellHeaderRenderer.EmptyIcon();

    public MutilColumnTableCellHeaderRenderer() {
        this.setHorizontalAlignment(0);
    }

    public void setHorizontalTextPosition(int textPosition) {
        this.horizontalTextPositionSet = true;
        super.setHorizontalTextPosition(textPosition);
    }

    public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
        Icon icon = null;
        boolean var8 = false;
        if (table != null) {
            JTableHeader header = table.getTableHeader();
            if (header != null) {
                Color var10 = null;
                Color var11 = null;
                if (hasFocus) {
                    var10 = DefaultLookup.getColor(this, this.ui, "TableHeader.focusCellForeground");
                    var11 = DefaultLookup.getColor(this, this.ui, "TableHeader.focusCellBackground");
                }

                if (var10 == null) {
                    var10 = header.getForeground();
                }

                if (var11 == null) {
                    var11 = header.getBackground();
                }

                this.setForeground(var10);
                this.setBackground(var11);
                this.setFont(header.getFont());
                var8 = header.isPaintingForPrint();
            }

            if (!var8 && table.getRowSorter() != null) {
                if (!this.horizontalTextPositionSet) {
                    this.setHorizontalTextPosition(10);
                }

                SortOrder var12 = getColumnSortOrder(table, column);
                if (var12 != null) {
                    switch(var12) {
                        case ASCENDING:
                            icon = DefaultLookup.getIcon(this, this.ui, "Table.ascendingSortIcon");
                            break;
                        case DESCENDING:
                            icon = DefaultLookup.getIcon(this, this.ui, "Table.descendingSortIcon");
                            break;
                        case UNSORTED:
                            icon = DefaultLookup.getIcon(this, this.ui, "Table.naturalSortIcon");
                    }
                }
            }
        }

        this.setText(value == null ? "" : value.toString());
        this.setIcon(icon);
        this.sortArrow = icon;
        Border var13 = null;
        if (hasFocus) {
            var13 = DefaultLookup.getBorder(this, this.ui, "TableHeader.focusCellBorder");
        }

        if (var13 == null) {
            var13 = DefaultLookup.getBorder(this, this.ui, "TableHeader.cellBorder");
        }

        this.setBorder(var13);
        return this;
    }

    public static SortOrder getColumnSortOrder(JTable table, int columnIndex) {
        SortOrder sortOrder = null;
        if (table != null && table.getRowSorter() != null) {
            List sortKeys = table.getRowSorter().getSortKeys();
            columnIndex = table.convertColumnIndexToModel(columnIndex);
            if (sortKeys.size() > 0) {
                for(Object sortKey:sortKeys){
                    if(columnIndex == ((RowSorter.SortKey)sortKey).getColumn()){
                        sortOrder = ((RowSorter.SortKey)sortKey).getSortOrder();
                        break;
                    }
                }
            }
            return sortOrder;
        } else {
            return sortOrder;
        }
    }

    public void paintComponent(Graphics var1) {
        // 若配置TableHeader.rightAlignSortArrow為true梧躺，表頭單元格里的箭頭將居右顯示
        boolean var2 = DefaultLookup.getBoolean(this, this.ui, "TableHeader.rightAlignSortArrow", false);
        if (var2 && this.sortArrow != null) {
            this.emptyIcon.width = this.sortArrow.getIconWidth();
            this.emptyIcon.height = this.sortArrow.getIconHeight();
            this.setIcon(this.emptyIcon);
            super.paintComponent(var1);
            Point var3 = this.computeIconPosition(var1);
            this.sortArrow.paintIcon(this, var1, var3.x, var3.y);
        } else {
            super.paintComponent(var1);
        }

    }

    private Point computeIconPosition(Graphics var1) {
        FontMetrics var2 = var1.getFontMetrics();
        Rectangle var3 = new Rectangle();
        Rectangle var4 = new Rectangle();
        Rectangle var5 = new Rectangle();
        Insets var6 = this.getInsets();
        var3.x = var6.left;
        var3.y = var6.top;
        var3.width = this.getWidth() - (var6.left + var6.right);
        var3.height = this.getHeight() - (var6.top + var6.bottom);
        SwingUtilities.layoutCompoundLabel(this, var2, this.getText(), this.sortArrow, this.getVerticalAlignment(), this.getHorizontalAlignment(), this.getVerticalTextPosition(), this.getHorizontalTextPosition(), var3, var5, var4, this.getIconTextGap());
        int var7 = this.getWidth() - var6.right - this.sortArrow.getIconWidth();
        int var8 = var5.y;
        return new Point(var7, var8);
    }

    private class EmptyIcon implements Icon, Serializable {
        int width;
        int height;

        private EmptyIcon() {
            this.width = 0;
            this.height = 0;
        }

        public void paintIcon(Component var1, Graphics var2, int var3, int var4) {
        }

        public int getIconWidth() {
            return this.width;
        }

        public int getIconHeight() {
            return this.height;
        }
    }
}

運(yùn)行效果：

demo.png

圖中以第0列為主排序列，第1列為次排序列進(jìn)行排序傲绣。（若需要實(shí)現(xiàn)通過(guò)顯示1掠哥、2、3表明主排序列和次排序列秃诵，重寫(xiě)Renderer的getTableCellRendererComponent方法）