How to write a JTable state with data in xml file using XMLEndcoder in java

Question

I want to save JTable in xml file using XMLEncoder. When we are saving it into a file, getting an exception:

java.lang.InstantiationException: javax.swing.plaf.basic.BasicTableUI$Handler
Continuing ...
java.lang.Exception: XMLEncoder: discarding statement ColorPropertyTable.removeMouseMotionListener(BasicTableUI$Handler);
Continuing ...

you would need to save value (from JTable, better from XxxTableModel) not JTable, required iterating in rows and columns — mKorbel, Oct 08 '14 at 07:14
See [TableModel - JAXB example](http://stackoverflow.com/a/25966347/2587435). May be of interest — Paul Samsotha, Oct 08 '14 at 07:33

score 3 · Answer 1 · answered Jun 08 '15 at 17:55

This answer is based on aterai's example. It is a little more complete because it will also persist the column names:

import java.awt.*;
import java.awt.event.*;
import java.beans.*;
import java.io.*;
import java.util.Vector;
import javax.swing.*;
import javax.swing.table.*;

public class DefaultTableModelPersistenceDelegateTest
{
    private File file = new File("TableModel.xml");
    private final JTextArea textArea = new JTextArea();

    private final String[] columnNames = {"Column1", "Column2"};

    private final Object[][] data =
    {
        {"aaa", new Integer(1)},
        {"bbb\u2600", new Integer(2)}
    };

    private DefaultTableModel model = new DefaultTableModel(data, columnNames);
    private final JTable table = new JTable(model);

    public JComponent makeUI()
    {
        model.setColumnCount(5);
        JSplitPane sp = new JSplitPane(JSplitPane.VERTICAL_SPLIT);
        sp.setResizeWeight(.3);
        sp.setTopComponent(new JScrollPane(table));
        sp.setBottomComponent(new JScrollPane(textArea));

        JPanel p = new JPanel();
        p.add(new JButton(new AbstractAction("XMLEncoder")
        {
            @Override
            public void actionPerformed(ActionEvent e)
            {
                try
                {
                    OutputStream os = new BufferedOutputStream(new FileOutputStream(file));
                    XMLEncoder xe = new XMLEncoder(os);
                    xe.setPersistenceDelegate(DefaultTableModel.class, new DefaultTableModelPersistenceDelegate2());
                    xe.writeObject(model);
                    xe.close();

                    Reader r = new BufferedReader(new InputStreamReader(new FileInputStream(file), "UTF-8"));
                    textArea.read(r, null);
                }
                catch (IOException ex)
                {
                    ex.printStackTrace();
                }
            }
        }));

        p.add(new JButton(new AbstractAction("XMLDecoder")
        {
            @Override
            public void actionPerformed(ActionEvent e)
            {
                try
                {
                    InputStream is = new BufferedInputStream( new FileInputStream( file ));
                    XMLDecoder xd = new XMLDecoder(is);
                    model = (DefaultTableModel)xd.readObject();
                    table.setModel(model);
                }
                catch (IOException ex)
                {
                    ex.printStackTrace();
                }
            }
        }));

        p.add(new JButton(new AbstractAction("clear")
        {
            @Override
            public void actionPerformed(ActionEvent e)
            {
                model = new DefaultTableModel();
                table.setModel(model);
            }
        }));

        JPanel pnl = new JPanel(new BorderLayout());
        pnl.add(sp);
        pnl.add(p, BorderLayout.SOUTH);
        return pnl;
    }

    public static void main(String[] args)
    {
        EventQueue.invokeLater(new Runnable()
        {
            @Override public void run()
            {
                createAndShowGUI();
            }
        });
    }

    public static void createAndShowGUI()
    {
        JFrame f = new JFrame();
        f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        f.getContentPane().add(new DefaultTableModelPersistenceDelegateTest().makeUI());
        f.setSize(420, 340);
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }
}

//http://www.oracle.com/technetwork/java/persistence4-140124.html

class DefaultTableModelPersistenceDelegate extends DefaultPersistenceDelegate
{
    //  Initially creates an empty DefaultTableModel. The columns are created
    //  and finally each row of data is added to the model.

    @Override
    protected void initialize(Class<?> type, Object oldInstance, Object newInstance, Encoder encoder)
    {
        DefaultTableModel model= (DefaultTableModel)oldInstance;

        Vector<String> columnNames = new Vector<String>(model.getColumnCount());

        for (int i = 0; i < model.getColumnCount(); i++)
        {
            columnNames.add( model.getColumnName(i) );
        }

        Object[] columnNamesData = new Object[] { columnNames };
        encoder.writeStatement(new Statement(oldInstance, "setColumnIdentifiers", columnNamesData));

        Vector row = model.getDataVector();

        for (int i = 0; i < model.getRowCount(); i++)
        {
            Object[] rowData = new Object[] { row.get(i) };
            encoder.writeStatement(new Statement(oldInstance, "addRow", rowData));
        }
    }
}

aterai · Answer 2 · 2014-10-12T18:26:41.500

http://java.sun.com/products/jfc/tsc/articles/persistence4/
http://www.oracle.com/technetwork/java/persistence4-140124.html
Registering for Exception Notifications
Both XMLEncoder and XMLDecoder catch exceptions and are typically able to recover from them, allowing the parts of the archive not affected by the exception to be written or read. You can find out more about any exceptions raised in the encoding and decoding processes by registering an ExceptionListener as follows:
...

enter image description here

Example

import java.awt.*;
import java.awt.event.*;
import java.beans.*;
import java.io.*;
import java.util.Vector;
import javax.swing.*;
import javax.swing.table.*;

public class DefaultTableModelPersistenceDelegateTest {
  private final JTextArea textArea = new JTextArea();

  private final String[] columnNames = {"A", "B"};
  private final Object[][] data = {
    {"aaa", "ccccccc"}, {"bbb", "\u2600\u2601\u2602\u2603"}
  };
  private DefaultTableModel model = new DefaultTableModel(data, columnNames);
  private final JTable table = new JTable(model);

  public JComponent makeUI() {
    JSplitPane sp = new JSplitPane(JSplitPane.VERTICAL_SPLIT);
    sp.setResizeWeight(.5);
    sp.setTopComponent(new JScrollPane(table));
    sp.setBottomComponent(new JScrollPane(textArea));

    JPanel p = new JPanel();
    p.add(new JButton(new AbstractAction("XMLEncoder") {
      @Override public void actionPerformed(ActionEvent e) {
        try {
          File file = File.createTempFile("output", ".xml");
          try (OutputStream os = new BufferedOutputStream(new FileOutputStream(file))) {
            XMLEncoder xe = new XMLEncoder(os);
            xe.setPersistenceDelegate(
                DefaultTableModel.class, new DefaultTableModelPersistenceDelegate());
//          xe.setExceptionListener(new ExceptionListener() {
//              @Override public void exceptionThrown(Exception exception) {
//                  //XXX: exception.printStackTrace();
//              }
//          });
//          xe.writeObject(table);
            xe.writeObject(model);
            //xe.flush();
            xe.close();
          }
          try (Reader r = new BufferedReader(
              new InputStreamReader(new FileInputStream(file), "UTF-8"))) {
            textArea.read(r, "temp");
          }
        } catch (IOException ex) {
          ex.printStackTrace();
        }
      }
    }));
    p.add(new JButton(new AbstractAction("XMLDecoder") {
      @Override public void actionPerformed(ActionEvent e) {
        try (InputStream is = new BufferedInputStream(
            new ByteArrayInputStream(textArea.getText().getBytes("UTF-8")))) {
          XMLDecoder xd = new XMLDecoder(is);
          model = (DefaultTableModel) xd.readObject();
          table.setModel(model);
        } catch (IOException ex) {
          ex.printStackTrace();
        }
      }
    }));
    p.add(new JButton(new AbstractAction("clear") {
      @Override public void actionPerformed(ActionEvent e) {
        model = new DefaultTableModel();
        table.setModel(model);
      }
    }));

    JPanel pnl = new JPanel(new BorderLayout());
    pnl.add(sp);
    pnl.add(p, BorderLayout.SOUTH);
    return pnl;
  }
  public static void main(String[] args) {
    EventQueue.invokeLater(new Runnable() {
      @Override public void run() {
        createAndShowGUI();
      }
    });
  }
  public static void createAndShowGUI() {
    JFrame f = new JFrame();
    f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    f.getContentPane().add(new DefaultTableModelPersistenceDelegateTest().makeUI());
    f.setSize(320, 240);
    f.setLocationRelativeTo(null);
    f.setVisible(true);
  }
}
//http://web.archive.org/web/20090806075316/http://java.sun.com/products/jfc/tsc/articles/persistence4/
//http://www.oracle.com/technetwork/java/persistence4-140124.html
class DefaultTableModelPersistenceDelegate extends DefaultPersistenceDelegate {
  @Override protected void initialize(
      Class<?> type, Object oldInstance, Object newInstance, Encoder encoder) {
    super.initialize(type, oldInstance,  newInstance, encoder);
    DefaultTableModel m = (DefaultTableModel) oldInstance;
//         Vector v = m.getDataVector();
//         for (int i = 0; i < m.getRowCount(); i++) {
//             encoder.writeStatement(
//               new Statement(oldInstance, "addRow", new Object[] { (Vector) v.get(i) }));
//         }
    for (int row = 0; row < m.getRowCount(); row++) {
      for (int col = 0; col < m.getColumnCount(); col++) {
        Object[] o = new Object[] {m.getValueAt(row, col), row, col};
        encoder.writeStatement(new Statement(oldInstance, "setValueAt", o));
      }
    }
  }
}

Hi aterai, xml file not created. – Arvind Singh Oct 11 '14 at 05:42 — Arvind Singh, Oct 11 '14 at 05:42
@ArvindSingh I fixed the suffix. – aterai Oct 11 '14 at 05:57 — aterai, Oct 11 '14 at 05:57

How to write a JTable state with data in xml file using XMLEndcoder in java

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