Here you can find a Formatter-Implementation which is able to format double values in JFormattedTextfield as time format like “01:30″ and vice versa, i.e. needed for duration inputs. Furthermore you don’t need to input the :-separator, “0130″ will be automatically translated to “01:30″ . The formatter is also able to allow ‘native’ double inputs like “1.5″ or even “1,5″.

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74

import java.text.ParseException;
import javax.swing.text.DefaultFormatter;
 
/**
 * <p>
 * This format converts a double value into a time format like 10:30 and vice versa.
 * </p>
 * <p>
 * Furthermore it checks if the input string<br />
 * a) can be assumed as time format without :-separator ("1030" -> 10:30)<br />
 * or<br />
 * b) is parseble as 'native' double value (like "0.5" = 00:30). It allows also inputs like "1,5".
 * </p>
 * 
 * @author denis[@]ibs-aachen.de
 */
public class DoubleTimeFormatter extends DefaultFormatter {
	private static final long serialVersionUID = -60169060463898543L;
 
	@Override
	public Object stringToValue(String string) throws ParseException {
		string = string.replace(',', '.');
 
		if (string.length() == 4) {
			try {
				Integer.parseInt(string); // check that it does only contain numbers
				String newString = string.substring(0, 2);
				newString += ":";
				newString += string.substring(2, 4);
				string = newString;
			} catch (NumberFormatException e) {
				// not possible/necessary to manipulate string to time-format
			}
		}
 
		Double d;
		try {
			d = Double.parseDouble(string);
			return d;
		} catch (NumberFormatException e) {
			// continue trying to parse time-format
		}
 
		d = new Double(0.);
		if (string.contains(":")) {
			String[] parts = string.split("[:]");
			if (parts.length > 0) {
				d += ("".equals(parts[0].trim()) ? 0 : Integer.parseInt(parts[0].trim()));
			}
			if (parts.length == 2) {
				d += ("".equals(parts[1].trim()) ? 0 : Integer.parseInt(parts[1].trim()) / 60.);
			}
		} else {
			d += ("".equals(string.trim()) ? 0 : Integer.parseInt(string.trim()));
		}
		return d;
	}
 
	@Override
	public String valueToString(Object value) throws ParseException {
		if (value == null) {
			return "";
		}
		StringBuffer toAppendTo = new StringBuffer();
		try {
			Double d = (Double) value;
			int n = d.intValue();
			toAppendTo.append(String.format("%02d:%02d", n, (int) ((d - n) * 60)));
		} catch (ClassCastException e) {
			throw new NumberFormatException("Need double value!");
		}
		return toAppendTo.toString();
	}
}

Add it to your textfield like this:

1

JFormattedTextField textfield = new JFormattedTextField(new DoubleTimeFormatter());

Feedback appreciated ;o)