자바 문자열 숫자인지 확인

자바 문자열이 숫자인지 확인하기

• Double.parseDouble

  public class NumbericYn {
    public static void main(String[] args) {
        String str = '123.0';
        boolean numberYn = parseDouble(str);
        System.out.println(numberYn);
    }
  
    public static boolean numbericYn(String str) {
        try {
            Double.parseDouble(str);
            return true;
        } catch (NumberFormatException ex) {
            return false;
        }
    }
  }

• Apache Commons Lang

  public class NumbericYn {
    public static void main(String[] args) {
        String str = '123.0';
        boolean numberYn = parseDouble(str);
        System.out.println(numberYn);
    }
  
    public static boolean numbericYn(String str) {
        return NumberUtils.isNumber(str);
    }
  }