What is ObjectUtils.requireNonEmpty() in Java?
requireNonEmpty() is a ObjectUtils class that is used to check whether a specified object reference is not null or not empty according to the isEmpty() method. If the specified object reference is either null or empty, the method throws an exception with the specified message.
How to import ObjectUtils
The definition of ObjectUtils can be found in the Apache Commons Lang package, which we can add to the Maven project by adding the following dependency to the pom.xml file:
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.12.0</version>
</dependency>
For other versions of the commons-lang package, refer to the Maven Repository.
You can import the ObjectUtils class as follows:
import org.apache.commons.lang3.ObjectUtils;
Syntax
public static <T> T requireNonEmpty(T obj, String message)
Parameters
obj: The object to check of typeT.message: The exception message if the object isnullor empty.
Return value
This method returns the input object if it is not null.
Code
import org.apache.commons.lang3.ObjectUtils;public class Main{public static void main(String[] args) {// Example 1String object = "hello";System.out.printf("ObjectUtils.requireNonEmpty(%s) = %s", object, ObjectUtils.requireNonEmpty(object));System.out.println();// Example 2object = "";String message = "Object must not be empty/null";System.out.printf("ObjectUtils.requireNonEmpty(%s) = %s", object, ObjectUtils.requireNonEmpty(object, message));System.out.println();}}
Output
The output of the code will be as follows:
ObjectUtils.requireNonEmpty(hello) = hello
Exception in thread "main" java.lang.IllegalArgumentException: Object must not be empty/null
at org.apache.commons.lang3.ObjectUtils.requireNonEmpty(ObjectUtils.java:1241)
at Main.main(Main.java:12)
Explanation
Example 1
object="hello"
The method returns hello because the object is neither empty nor null.
Example 2
object=""
The method throws an IllegalArgumentException with the exception message, as Object must not be empty/null.