importjava.util.Scanner;// 导入Scanner类以获取用户输入publicclassEmptyStringExample{publicstaticvoidmain(String[]args){Scannerscanner=newScanner(System.in);// 创建Scanner对象try{System.out.print("请输入一个字符串: ");// 提示用户输入Stringinput=scanner.nextLine();// 读取用户输入的字符串// 检查输...
publicclassStringNullOrEmptyCheck{ publicstaticvoidmain(String[] args){ // 示例1:测试一个为null的字符串 Stringstring1=null; checkString(string1); // 示例2:测试一个空字符串 Stringstring2=""; checkString(string2); // 示例3:测试一个非空非null的字符串 Stringstring3="Hello, World!"; chec...
publicclassStringCheck{publicstaticvoidmain(String[]args){// 示例调用Stringstr1=null;Stringstr2="";Stringstr3="Hello, World!";System.out.println("str1 is empty: "+isStringEmpty(str1));// trueSystem.out.println("str2 is empty: "+isStringEmpty(str2));// trueSystem.out.println("str3...
publicclassStringNullOrEmptyCheck{publicstaticvoidmain(String[] args){// 示例1:测试一个为null的字符串Stringstring1=null; checkString(string1);// 示例2:测试一个空字符串Stringstring2=""; checkString(string2);// 示例3:测试一个非空非null的字符串Stringstring3="Hello, World!"; checkString(stri...
class Main { public static void main(String[] args) { // create null, empty, and regular strings String str1 = null; String str2 = ""; String str3 = " "; // check if str1 is null or empty System.out.println("str1 is " + isNullEmpty(str1)); // check if str2 is null...
public static void main(String[] args) { String str1 = null; String str2 = ""; String str3 = "Hello, World!"; // Check if str1 is null or empty if (str1 == null || str1.length() == 0) { System.out.println("str1 is null or empty."); } else { System.out.println(...
2. StringisBlank()Example Java program to check if a given string is blank or not. "ABC".isBlank() //false " ABC ".isBlank() //false " ".isBlank() //true "".isBlank() ) //true 3. Difference betweenisBlank()andisEmpty()
Check if String is Null or Empty in Java Java: Check if String is Numeric How to Convert String to int in Java Reverse a String in Java Convert int to String in Java How to Split a String in Java: Different Examples Convert Char to String in Java ...
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-199,输出结果将是false; 而第二方式则可以通过修改正则表达式实现校验负数,将正则表达式修改为“^-?[0-...
还是 string ==null || string.isEmpty()一般用string == null || string.trim().length() == ...