May 16, 2020 - The if statement says "if it's null OR it's empty" So, if the string is null the "isEmpty" part will NOT be executed.

January 8, 2024 - Like Guava, it won’t check if a string only contains whitespace but checks whether a given string is null or empty. There are several ways to check whether a string is empty or not. Often, we also want to check if a string is blank, meaning that it consists of only whitespace characters. The most convenient way is to use Apache Commons Lang, which provides helpers such as StringUtils.isBlank. If we want to stick to plain Java, we can use a combination of String#trim with either String#isEmpty or String#length.

December 17, 2024 - Here, StringUtils.isBlank() checks if str is null, empty, or made solely of whitespace (spaces, tabs, new line characters). Very useful when the mere presence of whitespace should also classify the string as "empty". Recognize the enhancements in Java 11 including new String methods.

February 28, 2023 - String string = "Hello there"; if (string == null || string.equals("") || string.trim().equals("")) System.out.println("String is null, empty or blank"); else System.out.println("String is neither null, empty nor blank"); In much the same fashion as the before, if the trimmed string is "", it was either empty from the get-go, or was a blank string with 0..n whitespaces: ... The Apache Commons is a popular Java library that provides further functionality.

October 11, 2023 - “A null String in Java is literally equal to a reserved word “null”. It means the String that does not point to any physical address.” In Java programming language, a “null” String is used to refer to nothing.

Oracle | Hardware and Software, Engineered to Work Together ... The Java programming language distinguishes between null and empty strings. An empty string is a string instance of zero length, whereas a null string has no value at all.

February 25, 2025 - To prevent this, it is crucial to check for null before performing operations on a variable. An empty String ("") has zero characters but still exists in memory, specifically in the heap where Java stores objects.

August 4, 2025 - The length() method of the String class returns the number of characters in a string. If the length is 0, then the string is empty. The following is an example of checking if a string is null or empty using the length() method:

Answer (1 of 2): You’ve got the Apache StringUtils stuff which has methods like isNotBlank and methods to use a default String. Great for null/empty/space checks on String More generally, there are many ways of conveying empty in Java. None of them are good.

August 2, 2023 - Empty String: An empty string is a string object that exists in memory, but it contains no characters. It has a length of 0. The equals() method can be used to check if a string is null-safe and prevents a NullPointerException.

July 16, 2024 - Apache Commons Lang 3 is a widely used library. Its ArrayUtils class provides a rich set of utilities, making array manipulation easier. The class offers an isEmpty() method to check whether an array is null or empty.

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Become a certified Java programmer. Try Programiz PRO! ... 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 or empty System.out.println("str2 is " + isNullEmpty(str2)); // check if str3 is null or empty System.out.println("str3 is " + isNullEmpty(str3)); } // method check if string is null or empty public static String isNullEmpty(String str) { // check if string is null if (str == null) { return "NULL"; } // check if string is empty else if(str.isEmpty()){ return "EMPTY"; } else { return "neither NULL nor EMPTY"; } } }

if(stirng != null && string.trim().length() > 0){ System.out.println("String is not null and not empty"); } You can use this solution if your program doesn't consider a String with only white-space as a non-empty. If you load data from the database or stored data into the database it's better to trim() them before using them to avoid pesky issues due to whitespaces. That's all about how to check if String is not null and not empty in Java.

March 19, 2025 - What is the best way to check if a String is null or empty in Java? I’m currently parsing HTML data, and sometimes the String can be null or empty when the expected word doesn’t match. To handle this, I wrote the following check: if(string.equals(null) || string.equals("")){ Log.d("iftrue", "seem to be true"); }else{ Log.d("iffalse", "seem to be false"); } However, when I remove string.equals(""), the condition doesn’t work correctly.

The Java programming language distinguishes between null and empty strings. An empty string is a string instance of zero length, whereas a null string has no value at all.

November 28, 2023 - Use Cases: Ideal for straightforward null checks where performance is a concern. In Java 9 and later, you can use Objects.requireNonNullElse from java.util.Objects. ... Objects.requireNonNullElse(str, ""): Returns str if it’s non-null; otherwise, returns an empty string. It’s a clean and readable way to handle null values. Performance: Comparable to the ternary operator, with slightly more overhead due to the method call. Use Cases: Recommended for applications using Java 9 or newer, especially where readability and standard library solutions are preferred.

String myStr1 = "Hello"; String myStr2 = ""; System.out.println(myStr1.isEmpty()); System.out.println(myStr2.isEmpty()); ... The isEmpty() method checks whether a string is empty or not.

February 22, 2024 - However, as a recommendation according ... be used. In Java, you can check if an object is null by using the '==' operator to compare the object reference with null....