Java判断字符串是不是数字

描述：通过Java判断一个字符串，是不是数字。这里包括正数、负数、浮点数、科学计数法

代码：

import java.util.regex.Pattern;

public class Test {

    public static void main(String[] args) {
        System.out.println(isNumeric("12.23"));
        System.out.println(isNumeric("+10"));
        System.out.println(isNumeric("-0.12"));
        System.out.println(isNumeric("1.2E5"));
        System.out.println(isNumeric("1.2D5"));
        System.out.println(isNumeric("dasd"));
    }

    public static boolean isNumeric(String str) {
        if (null == str || "".equals(str)) {
            return false;
        }
        String regx = "[+-]*\\d+\\.?\\d*[Ee]*[+-]*\\d+";
        Pattern pattern = Pattern.compile(regx);
        boolean isNumber = pattern.matcher(str).matches();
        if (isNumber) {
            return isNumber;
        }
        regx = "^[-\\+]?[.\\d]*$";
        pattern = Pattern.compile(regx);
        return pattern.matcher(str).matches();
    }
}

执行结果：