JDK5.0的11个主要新特征

Flag

Purpose

Example

+

Prints sign for positive and negative numbers

+3333.33

space

Adds a space before positive numbers

| 3333.33|

0

Adds leading zeroes

003333.33

-

Left-justifies field

|3333.33 |

(

Encloses negative number in parentheses

(3333.33)

,

Adds group separators

3,333.33

# (for f format)

Always includes a decimal point

3,333.

# (for x or oformat)

Adds 0x or 0 prefix

0xcafe

^

Converts to upper case

0XCAFE

$

Specifies the index of the argument to be formatted; for example, %1$d %1$x prints the first argument in decimal and hexadecimal

159 9F

<

Formats the same value as the previous specification; for example, %d %<x prints the same number in decimal and hexadecimal