学步园

项目需要这样一个转换，找了找，没找到现成的，只好自己写了个。

import java.util.Arrays;<br /> public class TestEx {<br /> public static void main(String[] args) {<br /> for (int i = 1; i < 21; i++) {<br /> char[] c = new char[i];<br /> Arrays.fill(c, '1');<br /> String tmpStr = new String(c);<br /> System.out.println(tmpStr + ": " + translate(tmpStr));<br /> }<br /> }<br /> public static String translate(String testStr) {<br /> int commaNum = (testStr.length() - 1) / 3;<br /> for (int i = 0; i < commaNum; i++) {<br /> testStr = testStr.replaceAll("(//d{3},)*//d{3}$", ",$0");<br /> }<br /> return testStr;<br /> }<br /> }<br />

注： 将正则表达式中的//换回\\

结果：<br /> 1: 1<br /> 11: 11<br /> 111: 111<br /> 1111: 1,111<br /> 11111: 11,111<br /> 111111: 111,111<br /> 1111111: 1,111,111<br /> 11111111: 11,111,111<br /> 111111111: 111,111,111<br /> 1111111111: 1,111,111,111<br /> 11111111111: 11,111,111,111<br /> 111111111111: 111,111,111,111<br /> 1111111111111: 1,111,111,111,111<br /> 11111111111111: 11,111,111,111,111<br /> 111111111111111: 111,111,111,111,111<br /> 1111111111111111: 1,111,111,111,111,111<br /> 11111111111111111: 11,111,111,111,111,111<br /> 111111111111111111: 111,111,111,111,111,111<br /> 1111111111111111111: 1,111,111,111,111,111,111<br /> 11111111111111111111: 11,111,111,111,111,111,111