public static boolean isNumeric(String str)Checks if the String contains only unicode digits. A decimal point is not a unicode digit and returns false. null will return false. An empty String ("") will return true. StringUtils.isNumeric(null) = false StringUtils.isNumeric("") = true String...
http://jakarta.apache.org/commons/lang/api-release/index.html下面的解释:isNumericpublicstaticbooleanisNumeric(String str)Checksifthe String contains only unicode digits. A decimal point is not a unicode digit and returnsfalse.nullwillreturnfalse. An empty String ("") willreturntrue. StringUtils.is...
3.StringUtils.isNumeric public static boolean isNumeric7(String str) { return StringUtils.isNumeric(str); } 1. 2. 3. 4.StringUtils.isNumericSpace public static boolean isNumeric8(String str) { return StringUtils.isNumericSpace(str); } 1. 2. 3. 测试并比较 默认情况下,文章中的数字都指的是...
StringUtils.isNumeric("12 3") = false StringUtils.isNumeric("ab2c") = false StringUtils.isNumeric("12-3") = false StringUtils.isNumeric("12.3") = false 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. Parameters: str - the String to check, may be null Returns: true if only contains ...
class Test { public static void main(String[] args) { String str = "129843875"; boolean containsOnlyDigits = true; for (int i = 0; i < str.length(); i++) { if (!Character.isDigit(str.charAt(i))) { // in case that a char is NOT a digit, enter to the if code block cont...
StringUtils.isNumeric("12-3") = false StringUtils.isNumeric("12.3") = false Parameters:str - the String to check, may be null Returns:true if only contains digits, and is non-null 上面三种方式中，第二种方式比较灵活。第一、三种方式只能校验不含负号“-”的数字，即输入一个负数...
public class CheckDigit { private static Scanner input; public static void main(String[] args) { System.out.print("Enter a String:"); input = new Scanner(System.in); String str = input.nextLine(); if (CheckString(str)) { System.out.println(str + " is numeric"); } else { System...
public static boolean isNumeric(String strNum) { if (strNum == null) { return false; } try { double d = Double.parseDouble(strNum); } catch (NumberFormatException nfe) { return false; } return true; } Let’s see this method in action: ...
Original String: 123456 Check the said string is a valid hex code or not? false Original String: #eaecff Check the said string is a valid hex code or not? true Original String: #FF0000 Check the said string is a valid hex code or not? true Original String: #DD5C5C Check the said ...
In this quick tutorial, we’ll illustrate how we cancheck if aStringis containing at least one of each of the following: uppercase letter, lowercase letter, digit or special character in Java. 2. Using Regular Expressions One of the ways to perform our check is by using regular expressions...