import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.text.DateFormat;
import java.util.GregorianCalendar;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.table.DefaultTableModel;

import org.odftoolkit.simple.TextDocument;
import org.odftoolkit.simple.style.DefaultStyleHandler;
import org.odftoolkit.simple.style.Font;
import org.odftoolkit.simple.style.StyleTypeDefinitions.FontStyle;
import org.odftoolkit.simple.style.StyleTypeDefinitions.HorizontalAlignmentType;
import org.odftoolkit.simple.table.Cell;
import org.odftoolkit.simple.table.Table;
import org.odftoolkit.simple.text.Paragraph;

public class JTableToODT {

    private JTable table;
    private Object[] head;
    private String exportFile = "Tabelle.odt";

    public JTableToODT() {
        initGUI();
    }

    private void initGUI() {
        head = new Object[]{ "eins", "zwei", "drei", "vier", "f\u00FCnf" };
        Object[][] content = new Object[20][5];
        for (int i = 0; i < content.length; i++) {
            for (int j = 0; j < content[i].length; j++) {
                content[i][j] = (i + 1) + "." + (j + 1);
            }
        }
        DefaultTableModel model = new DefaultTableModel(content, head);
        table = new JTable(model);
        table.setShowGrid(true);
        table.setAutoCreateRowSorter(true);
        table.setBackground(Color.LIGHT_GRAY);
        JFrame frame = new JFrame("Tabelle zu ODT");
        frame.add(new JScrollPane(table), BorderLayout.CENTER);
        JButton butt = new JButton("Export");
        butt.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                expToODT(exportFile);
            }
        });
        frame.add(butt, BorderLayout.SOUTH);
        frame.pack();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public void expToODT(final String fileName) {
        final DefaultTableModel model = (DefaultTableModel) table.getModel();
        final int clmCnt = table.getColumnCount();
        final int rowCnt = table.getRowCount();
        Thread t = new Thread() {
            @Override
            public void run() {
                TextDocument outputOdt = null;
                try {
                    outputOdt = TextDocument.newTextDocument();

                    // Header
                    Paragraph para = Paragraph.newParagraph(outputOdt);
                    para.applyHeading();
                    DateFormat df = DateFormat.getDateTimeInstance(
                            DateFormat.SHORT, DateFormat.SHORT);
                    para.setTextContent("Testtabelle - "
                            + df.format(new GregorianCalendar().getTime()));
                    outputOdt.getParagraphByIndex(0, false).remove();

                    // Tabelle
                    Table table = outputOdt.addTable(rowCnt + 1, clmCnt);
                    Cell cell;
                    Object value;
                    DefaultStyleHandler styleHandler;
                    Font normal = new Font("Helvetica", FontStyle.REGULAR, 8);
                    Font header = new Font("Helvetica", FontStyle.BOLD, 9);
                    for (int i = 0; i <= rowCnt; i++) {
                        for (int j = 0; j < clmCnt; j++) {
                            cell = table.getCellByPosition(j, i);
                            styleHandler = cell.getStyleHandler();
                            if (i == 0) {
                                styleHandler.getTextPropertiesForWrite()
                                        .setFont(header);
                                cell.setStringValue(head[j].toString());
                            } else {
                                value = model.getValueAt(
                                        JTableToODT.this.table
                                                .convertRowIndexToModel(i - 1),
                                        j);
                                cell.setHorizontalAlignment(
                                        HorizontalAlignmentType.LEFT);
                                styleHandler.getTextPropertiesForWrite()
                                        .setFont(normal);
                                cell.setStringValue(
                                        value == null ? "" : value.toString());
                            }
                        }
                    }
                    outputOdt.save(fileName);
                    String message = "";
                    if(new File(fileName).exists()) {
                        message = " wurde erstellt";
                    } else {
                        message = " konnte nicht erstellt werden";
                    }
                    JOptionPane.showMessageDialog(null, fileName + message);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        };
        t.start();
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> new JTableToODT());
    }
}