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corejava
Class Format

java.lang.Object
  |
  +--corejava.Format

public class Format
extends java.lang.Object

A class for formatting numbers that follows printf conventions. Also implements C-like atoi and atof functions

Constructor Summary
`Format(java.lang.String s)` Formats the number following `printf` conventions.

Method Summary
`static double`	`atof(java.lang.String s)` Converts a string of digits to a `double`
`static int`	`atoi(java.lang.String s)` Converts a string of digits (decimal, octal or hex) to an integer
`static long`	`atol(java.lang.String s)` Converts a string of digits (decimal, octal or hex) to a long integer
`java.lang.String`	`format(char c)` Formats a character into a string (like sprintf in C)
`java.lang.String`	`format(double x)` Formats a `double` into a string (like sprintf in C)
`java.lang.String`	`format(int x)` Formats an integer into a string (like sprintf in C)
`java.lang.String`	`format(long x)` Formats a long integer into a string (like sprintf in C)
`java.lang.String`	`format(java.lang.String s)` Formats a string into a larger string (like sprintf in C)
`static void`	`main(java.lang.String[] a)` a test stub for the format class
`static void`	`printf(java.lang.String fmt, char x)` prints a formatted number following printf conventions
`static void`	`printf(java.lang.String fmt, double x)` prints a formatted number following printf conventions
`static void`	`printf(java.lang.String fmt, int x)` prints a formatted number following printf conventions
`static void`	`printf(java.lang.String fmt, long x)` prints a formatted number following printf conventions
`static void`	`printf(java.lang.String fmt, java.lang.String x)` prints a formatted number following printf conventions

Methods inherited from class java.lang.Object

clone, 
equals, 
finalize, 
getClass, 
hashCode, 
notify, 
notifyAll, 
toString, 
wait, 
wait, 
wait

Constructor Detail

Format

public Format(java.lang.String s)

Formats the number following printf conventions. Main limitation: Can only handle one format parameter at a time Use multiple Format objects to format more than one number

Parameters:

s - the format string following printf conventions The string has a prefix, a format code and a suffix. The prefix and suffix become part of the formatted output. The format code directs the formatting of the (single) parameter to be formatted. The code has the following structure

a % (required)
a modifier (optional)

+
forces display of + for positive numbers
0
show leading zeroes
-
align left in the field
space
prepend a space in front of positive numbers
#
use "alternate" format. Add 0 or 0x for octal or hexadecimal numbers. Don't suppress trailing zeroes in general floating point format.
an integer denoting field width (optional)
a period followed by an integer denoting precision (optional)
a format descriptor (required)

f
floating point number in fixed format
e, E
floating point number in exponential notation (scientific format). The E format results in an uppercase E for the exponent (1.14130E+003), the e format in a lowercase e.
g, G
floating point number in general format (fixed format for small numbers, exponential format for large numbers). Trailing zeroes are suppressed. The G format results in an uppercase E for the exponent (if any), the g format in a lowercase e.
d, i
integer in decimal
x
integer in hexadecimal
o
integer in octal
s
string
c
character

Throws:

java.lang.IllegalArgumentException - if bad format

Method Detail