java.util

Interface Formattable

public interface Formattable

The Formattable interface is used to provide customised formatting to arbitrary objects via the Formatter. The formatTo(java.util.Formatter, int, int, int) method is called for Formattable objects used with the 's' conversion operator, allowing the object to provide its own formatting of its internal data.

Thread safety is left up to the implementing class. Thus, Formattable objects are not guaranteed to be thread-safe, and users should make their own provisions for multiple thread access.

Since:

1.5

Author:

Tom Tromey (tromey@redhat.com), Andrew John Hughes (gnu_andrew@member.fsf.org)

Method Summary

Modifier and Type	Method and Description
void	formatTo(Formatter formatter, int flags, int width, int precision) Formats the object using the supplied formatter to the specification provided by the given flags, width and precision.

Method Detail

formatTo

void formatTo(Formatter formatter,
              int flags,
              int width,
              int precision)

Formats the object using the supplied formatter to the specification provided by the given flags, width and precision.

Parameters:

formatter - the formatter to use for formatting the object. The formatter gives access to the output stream and locale via Formatter.out() and Formatter.locale() respectively.

flags - a bit mask constructed from the flags in the FormattableFlags class. When no flags are set, the implementing class should use its defaults.

width - the minimum number of characters to include. A value of -1 indicates no minimum. The remaining space is padded with ' ' either on the left (the default) or right (if left justification is specified by the flags).

precision - the maximum number of characters to include. A value of -1 indicates no maximum. This value is applied prior to the minimum (the width). Thus, a value may meet the minimum width initially, but not when the width value is applied, due to characters being removed by the precision value.

Throws:

IllegalFormatException - if there is a problem with the syntax of the format specification or a mismatch between it and the arguments.