Ho to fill JTable in such a way that each cell contains a `String` consisted of two lines?

Question

Is it possible to fill JTable in such a way that each cell contains a String consisted of two lines?

String cellText = "Line 1 \n Line 2";

In my JTable I see cellText displayed as a single line.

Answer 1

You'll want to use a custom JTextArea renderer.

http://www.coderanch.com/t/340609/GUI/java/JTable-Custom-Cell-Renderer-JTextArea

This is one I've used over the years:

import javax.swing.*;
import javax.swing.table.*;
import java.awt.*;
import java.util.*;

public class TextAreaRenderer extends JTextArea implements TableCellRenderer {

    private final DefaultTableCellRenderer adaptee = new DefaultTableCellRenderer();
    /** map from table to map of rows to map of column heights */
    private final Map cellSizes = new HashMap();


    public TextAreaRenderer() {
        setLineWrap(true);
        setWrapStyleWord(true);
    }

    public Component getTableCellRendererComponent(
            JTable table, Object obj, boolean isSelected,
            boolean hasFocus, int row, int column) {

        // set the colours, etc. using the standard for that platform
        adaptee.getTableCellRendererComponent(table, obj,
                isSelected, hasFocus, row, column);
        setForeground(adaptee.getForeground());
        setBackground(adaptee.getBackground());
        setBorder(adaptee.getBorder());
        setFont(adaptee.getFont());
        setText(adaptee.getText());


        // This line was very important to get it working with JDK1.4
        TableColumnModel columnModel = table.getColumnModel();
        setSize(columnModel.getColumn(column).getWidth(), 100000);
        int height_wanted = (int) getPreferredSize().getHeight();
        addSize(table, row, column, height_wanted);
        height_wanted = findTotalMaximumRowSize(table, row);
        if (height_wanted != table.getRowHeight(row)) {
            table.setRowHeight(row, height_wanted);
        }
        return this;
    }

    @SuppressWarnings("unchecked")
    private void addSize(JTable table, int row, int column, int height) {
        Map rows = (Map) cellSizes.get(table);
        if (rows == null) {
            cellSizes.put(table, rows = new HashMap());
        }
        Map rowheights = (Map) rows.get(new Integer(row));
        if (rowheights == null) {
            rows.put(new Integer(row), rowheights = new HashMap());
        }
        rowheights.put(new Integer(column), new Integer(height));
    }

    /**
     * Look through all columns and get the renderer.  If it is
     * also a TextAreaRenderer, we look at the maximum height in
     * its hash table for this row.
     */
    private int findTotalMaximumRowSize(JTable table, int row) {
        int maximum_height = 0;
        Enumeration columns = table.getColumnModel().getColumns();
        while (columns.hasMoreElements()) {
            TableColumn tc = (TableColumn) columns.nextElement();
            TableCellRenderer cellRenderer = tc.getCellRenderer();
            if (cellRenderer instanceof TextAreaRenderer) {
                TextAreaRenderer tar = (TextAreaRenderer) cellRenderer;
                maximum_height = Math.max(maximum_height,
                        tar.findMaximumRowSize(table, row));
            }
        }
        return maximum_height;
    }

    private int findMaximumRowSize(JTable table, int row) {
        Map rows = (Map) cellSizes.get(table);
        if (rows == null) {
            return 0;
        }
        Map rowheights = (Map) rows.get(new Integer(row));
        if (rowheights == null) {
            return 0;
        }
        int maximum_height = 0;
        for (Iterator it = rowheights.entrySet().iterator();
                it.hasNext();) {
            Map.Entry entry = (Map.Entry) it.next();
            int cellHeight = ((Integer) entry.getValue()).intValue();
            maximum_height = Math.max(maximum_height, cellHeight);
        }
        return maximum_height;
    }
}

which you would call with something like this:

table.getColumn("Column").setCellRenderer(new TextAreaRenderer());

Answer 2

JTable Cell data follows html syntax and rules. So you can use <br> to put line separator. hope this helps.