Java输出格式

Question

I was wondering if Java has some sort of class to help on output formatting. I know in C++, in iomanip, there is a method call setw. I was wondering if Java has something similar to this.

Answer 1

Have a look at java.util.Formatter .

String.format() provides a convenient wrapper.

For example (modified from an example on the link):

   String s = String.format("e = %+10.4f", Math.E);

It goes beyond C's ?printf formats. For example, it supports an optional locale, and format symbols can be associated with an argument by explicit index rather than implicit.

Edit: Fixed the link above.

Answer 2

String.format(..)和可能的java.text.*

Answer 3

有Formatter类及其变体：String.format，PrintStream.printf。

Answer 4

The simplest approach is to use printf() which works much the same as printf() in C.

double pi = Math.PI;
System.out.printf ("pi = %5.3f%n", pi);