java - 在私有(private) DefaultTableModel 中引用

Question

这是我的带有多个搜索和排序的简单 JTable 的代码。这可能是一个相对简单的问题，但是当我运行代码时，在“私有(private) DefaultTableModel 模型”中引用“aData”和“aHeaders”时出现错误。另外，在这个小问题解决之后，我还会遇到其他错误或异常吗？ IE。空指针异常

import javax.swing.*;
import java.awt.*;
import java.io.*;
import java.lang.*;
import java.awt.event.*;
///////////
import javax.swing.border.EmptyBorder;
import javax.swing.event.*;
import javax.swing.text.Document;
import javax.swing.table.TableRowSorter;
import java.util.List;
import java.util.ArrayList;
import java.util.Comparator;
///////////
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;
import java.util.logging.Level;
import java.util.logging.Logger;
import static javax.swing.JFrame.EXIT_ON_CLOSE;
import javax.swing.table.*;

public class JtableIe
{
    JFrame myMainWindow = new JFrame("Compare Tables");

    JPanel  firstPanel = new JPanel();

    JScrollPane myScrollTable;
    JTable myTable;
    JTextField srchFld1;
    JTextField srchFld2;
    TableRowSorter sorter;
    JLabel srchLbl1 = new JLabel();
    JLabel srchLbl2 = new JLabel();

    public void runGUI()
    {
        myMainWindow.setBounds(10, 10, 1296, 756);

        myMainWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        myMainWindow.setLayout(new GridLayout(1,1));

        createFirstPanel();

        myMainWindow.getContentPane().add(firstPanel);

        myMainWindow.setVisible(true);
    }

    public void createFirstPanel()
    {
        firstPanel.setLayout(null);

        srchLbl1.setLocation(0,0);
        srchLbl1.setSize(150,26);
        srchLbl1.setText("Name Search:");
        firstPanel.add(srchLbl1);

        srchLbl2.setLocation(660,0);
        srchLbl2.setSize(150,26);
        srchLbl2.setText("ID Search:");
        firstPanel.add(srchLbl2);

        String[] aHeaders = {"Name","ID","Number 1","Number 2","Time","Date"};
        Object[][] aData = new Object[15][6];
        myTable = new JTable(model);
        ///////Data////////
        aData[0][0] = "John";
        aData[0][1] = "JS96";
        aData[0][2] = "1";
        aData[0][3] = "186";
        aData[0][4] = "1h 23m";
        aData[0][5] = getJavaDate("12-11-2015");

        aData[1][0] = "David";
        aData[1][1] = "DB36";
        aData[1][2] = "2";
        aData[1][3] = "111852";
        aData[1][4] = "2h 55m";
        aData[1][5] = getJavaDate("12-11-2020");

        aData[2][0] = "Daniel";
        aData[2][1] = "DK73";
        aData[2][2] = "3";
        aData[2][3] = "2921";
        aData[2][4] = "1h 55m";
        aData[2][5] = getJavaDate("12-11-2014");

        aData[3][0] = "Janis";
        aData[3][1] = "JW84";
        aData[3][2] = "4";
        aData[3][3] = "6512";
        aData[3][4] = "12h 26m";
        aData[3][5] = getJavaDate("13-11-2015");

        aData[4][0] = "Adam";
        aData[4][1] = "AF98";
        aData[4][2] = "5";
        aData[4][3] = "7524";
        aData[4][4] = "5h 47m";
        aData[4][5] = getJavaDate("11-11-2015");

        aData[5][0] = "Matthew";
        aData[5][1] = "MB55";
        aData[5][2] = "6";
        aData[5][3] = "4989";
        aData[5][4] = "80h 30m";
        aData[5][5] = getJavaDate("11-11-2015");

        aData[6][0] = "Lewis";
        aData[6][1] = "LS23";
        aData[6][2] = "7";
        aData[6][3] = "56321";
        aData[6][4] = "880h 20m";
        aData[6][5] = getJavaDate("11-11-2015");

        aData[7][0] = "Mark";
        aData[7][1] = "ML49";
        aData[7][2] = "8";
        aData[7][3] = "97456";
        aData[7][4] = "8h 42m";
        aData[7][5] = getJavaDate("11-11-2015");

        aData[8][0] = "Josh";
        aData[8][1] = "JT67";
        aData[8][2] = "9";
        aData[8][3] = "82135";
        aData[8][4] = "56h 13m";
        aData[8][5] = getJavaDate("11-11-2015");

        aData[9][0] = "Oliver";
        aData[9][1] = "OC98";
        aData[9][2] = "10";
        aData[9][3] = "152";
        aData[9][4] = "9h 9m";
        aData[9][5] = getJavaDate("11-11-2015");

        aData[10][0] = "Tom";
        aData[10][1] = "TS97";
        aData[10][2] = "11";
        aData[10][3] = "100";
        aData[10][4] = "0h 0m";
        aData[10][5] = getJavaDate("11-11-2015");

        aData[11][0] = "Emma";
        aData[11][1] = "EBS74";
        aData[11][2] = "12";
        aData[11][3] = "200";
        aData[11][4] = "0h 30m";
        aData[11][5] = getJavaDate("11-11-2015");

        aData[12][0] = "Lucy";
        aData[12][1] = "LK02";
        aData[12][2] = "13";
        aData[12][3] = "256";
        aData[12][4] = "7h 00m";
        aData[12][5] = getJavaDate("11-11-2015");

        aData[13][0] = "Patrick";
        aData[13][1] = "PM38";
        aData[13][2] = "14";
        aData[13][3] = "258";
        aData[13][4] = "2h 00m";
        aData[13][5] = getJavaDate("11-11-2015");

        aData[14][0] = "Nicola";
        aData[14][1] = "NB70";
        aData[14][2] = "15";
        aData[14][3] = "987";
        aData[14][4] = "100h 56m";
        aData[14][5] = getJavaDate("11-11-2015");
        //////////////

        myTable.setAutoCreateRowSorter(true);

        sorter = new TableRowSorter(myTable.getModel());
        List sortKeys = new ArrayList();
        sortKeys.add(new RowSorter.SortKey(0, SortOrder.ASCENDING));
        sorter.setSortKeys(sortKeys);
        sorter.setComparator(2, new AlphanumComparator());
        sorter.setComparator(3, new AlphanumComparator());
        sorter.setComparator(4, new AlphanumComparator());
        setRenderers();
        myTable.setRowSorter(sorter);



        DefaultRowSorter sorter = (DefaultRowSorter) myTable.getRowSorter();


        myScrollTable = new JScrollPane(myTable); 
        myScrollTable.setSize(1296,756); 
        myScrollTable.setLocation(0,25); 
        System.out.println("Creating compare table");

        srchFld1 = new JTextField(10);
        srchFld1.setSize(550,26); 
        srchFld1.setLocation(100,0);
        srchFld1.setToolTipText("Enter Name");
        firstPanel.add(srchFld1);

        srchFld2 = new JTextField(10);
        srchFld2.setSize(550,26); 
        srchFld2.setLocation(740,0);
        srchFld2.setToolTipText("Enter ID");
        firstPanel.add(srchFld2);

        //////////////////////
        Document doc = srchFld1.getDocument();
        DocumentListener listener = new DocumentListener() {

            @Override
            public void insertUpdate(DocumentEvent e) 
            {
                newFilter();
            }

            @Override
            public void removeUpdate(DocumentEvent e) 
            {
                newFilter();
            }

            @Override
            public void changedUpdate(DocumentEvent e) 
            {
                newFilter();
            }
        };
        doc.addDocumentListener(listener);

        ///////////////
        Document docb = srchFld2.getDocument();
        DocumentListener listenerb = new DocumentListener() {

            @Override
            public void insertUpdate(DocumentEvent e) 
            {
                newFilter();
            }

            @Override
            public void removeUpdate(DocumentEvent e) 
            {
                newFilter();
            }

            @Override
            public void changedUpdate(DocumentEvent e) 
            {
                newFilter();
            }
        };
        docb.addDocumentListener(listenerb);
        ///////////////

        firstPanel.add(myScrollTable);
    }

    private DefaultTableModel model = new DefaultTableModel(aData, aHeaders) {
        @Override
        public Class<?> getColumnClass(int column) 
        {
                return getValueAt(5, column).getClass();
        }
    };

    private static final DateFormat DATE_FORMAT = new SimpleDateFormat("dd/MM/yyyy");

    private void setRenderers() {
        myTable.setDefaultRenderer(Date.class, new DateRenderer());
    }

    private Date getJavaDate(String s) {
        try 
        {
            SimpleDateFormat sdf = new SimpleDateFormat("dd-MM-yyyy");
            Date d = sdf.parse(s);
            return d;
        } 

        catch (ParseException ex) 
        {
            Logger.getLogger(TableBasic.class.getName()).log(Level.SEVERE, null, ex);
            return null;
        }
    }

    private void newFilter()
    {
        RowFilter rf = null;
        try 
        {
            List<RowFilter<Object,Object>> filters = new ArrayList<RowFilter<Object,Object>>(2);
            filters.add(RowFilter.regexFilter(srchFld1.getText(), 0));
            filters.add(RowFilter.regexFilter(srchFld2.getText(), 1));
            rf = RowFilter.andFilter(filters);
        } 
        catch (java.util.regex.PatternSyntaxException e) 
        {
            return;
        }
        sorter.setRowFilter(rf);
    }

    public static void main(String[] args)
    {
        JtableIe ji = new JtableIe();
        ji.runGUI();
    }

    private class DateRenderer extends DefaultTableCellRenderer 
    {

        private static final long serialVersionUID = 1L;

        @Override
        public Component getTableCellRendererComponent(JTable myTable, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
            super.getTableCellRendererComponent(myTable, value, isSelected, hasFocus, row, column);
            if (!(value instanceof Date)) {
                return this;
            }
            setText(DATE_FORMAT.format((Date) value));
            return this;
        }
    }
}

AlphanumComparator 代码

 /*
 * The Alphanum Algorithm is an improved sorting algorithm for strings
 * containing numbers.  Instead of sorting numbers in ASCII order like
 * a standard sort, this algorithm sorts numbers in numeric order.
 *
 * The Alphanum Algorithm is discussed at http://www.DaveKoelle.com
 *
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

import java.util.Comparator;

/**
 * This is an updated version with enhancements made by Daniel Migowski,
 * Andre Bogus, and David Koelle
 *
 * To convert to use Templates (Java 1.5+):
 *   - Change "implements Comparator" to "implements Comparator<String>"
 *   - Change "compare(Object o1, Object o2)" to "compare(String s1, String s2)"
 *   - Remove the type checking and casting in compare().
 *
 * To use this class:
 *   Use the static "sort" method from the java.util.Collections class:
 *   Collections.sort(your list, new AlphanumComparator());
 */
public class AlphanumComparator implements Comparator
{
    private final boolean isDigit(char ch)
    {
        return ch >= 48 && ch <= 57;
    }

    /** Length of string is passed in for improved efficiency (only need to calculate it once) **/
    private final String getChunk(String s, int slength, int marker)
    {
        StringBuilder chunk = new StringBuilder();
        char c = s.charAt(marker);
        chunk.append(c);
        marker++;
        if (isDigit(c))
        {
            while (marker < slength)
            {
                c = s.charAt(marker);
                if (!isDigit(c))
                    break;
                chunk.append(c);
                marker++;
            }
        } else
        {
            while (marker < slength)
            {
                c = s.charAt(marker);
                if (isDigit(c))
                    break;
                chunk.append(c);
                marker++;
            }
        }
        return chunk.toString();
    }

    public int compare(Object o1, Object o2)
    {
        if (!(o1 instanceof String) || !(o2 instanceof String))
        {
            return 0;
        }
        String s1 = (String)o1;
        String s2 = (String)o2;

        int thisMarker = 0;
        int thatMarker = 0;
        int s1Length = s1.length();
        int s2Length = s2.length();

        while (thisMarker < s1Length && thatMarker < s2Length)
        {
            String thisChunk = getChunk(s1, s1Length, thisMarker);
            thisMarker += thisChunk.length();

            String thatChunk = getChunk(s2, s2Length, thatMarker);
            thatMarker += thatChunk.length();

            // If both chunks contain numeric characters, sort them numerically
            int result = 0;
            if (isDigit(thisChunk.charAt(0)) && isDigit(thatChunk.charAt(0)))
            {
                // Simple chunk comparison by length.
                int thisChunkLength = thisChunk.length();
                result = thisChunkLength - thatChunk.length();
                // If equal, the first different number counts
                if (result == 0)
                {
                    for (int i = 0; i < thisChunkLength; i++)
                    {
                        result = thisChunk.charAt(i) - thatChunk.charAt(i);
                        if (result != 0)
                        {
                            return result;
                        }
                    }
                }
            } else
            {
                result = thisChunk.compareTo(thatChunk);
            }

            if (result != 0)
                return result;
        }

        return s1Length - s2Length;
    }
}

Answer 1

你不能像这样引用“模型”。

您的代码顺序错误。首先需要创建包含列名称的列数组，然后创建包含数据的数据数组。然后，您使用这些变量来创建表模型并将表模型添加到表中。

代码可能类似于:

String[] aHeaders = {"Name","ID","Number 1","Number 2","Time","Date"};

Object[][] aData = new Object[15][6];

///////Data////////
aData[0][0] = "John";
aData[0][1] = "JS96";
aData[0][2] = "1";
aData[0][3] = "186";
aData[0][4] = "1h 23m";
aData[0][5] = getJavaDate("12-11-2015");
...

DefaultTableModel model = new DefaultTableModel(aData, aHeaders)
{
         @Override
        public Class<?> getColumnClass(int column) 
        {
            switch (column)
            {
                case 5: return Date.class;
                default: return Object.class;
            }
        }
};

myTable = new JTable( model );