Java... 如何生成一个 4 位整数

Question

I want to make an integer value from the range 1-9999. But the integer values should be always in 4 digits.

Like 0001, 0002, 0015, 0156, 1578

Answer 1

You can probably use String format of the integer you willing to, like this:

String.format("%04d", your integer));

This will always show missing 0 on the left on digits like 01 or 1.

Answer 2

System.out.format("%04d%n", n);

Answer 3

if you want to print 4 digit integer, use like this

System.out.printf("%04d%n",your integer);

if you want to store in a variable, use like this

String str=String.format("%04d", your integer));

Read more details about String format()

Answer 4

使用

String.format("%04d", your integer));