package chengyujia;import java.util.regex.Pattern;public class NumberUtil {/*** 判断一个字符串是否是数字。* * @param string* @return*/public static boolean isNumber(String string) {if (string == null)return false;Pattern pattern = pile("^-?\\d+(\\.\\d+)?$");return pattern.matcher(string).matches();}private static void isNumberTest() {System.out.println(isNumber("123"));System.out.println(isNumber("-123.456"));System.out.println(isNumber("123成宇佳456"));}public static void main(String[] args) {isNumberTest();}}
运行测试,控制台输出:
true
true
false