In this example, we take a look at a JUnit example of failing a test on NullPointerException.
Code Example:
import org.junit.jupiter.api.Test;
import static org.junit.jupiter.api.Assertions.assertThrows;
import static org.junit.jupiter.api.Assertions.fail;
public class JunitExceptionExample {
@Test
public void test() {
try {
String str = null;
str.toLowerCase();
} catch (NullPointerException nullPointerException) {
assertThrows(NullPointerException.class, () -> {
throw nullPointerException;
});
} catch (Exception exception) {
fail("Expected NullPointerException, but caught: " + exception.getClass().getSimpleName());
}
}
}
In the above example, we have made use of the assertThrows method from org.junit.jupiter.api.Assertions class of Junit 5.
For this example: The method asserts that execution of the supplied executable throws an exception of the expectedType (NullPointerException) and returns the exception. If there is no exception thrown by your code, or a different expectation other than NullPointerException is thrown assertThrows method will fail.
Facing issues? Have Questions? Post them here! I am happy to answer!
Rakesh (He/Him) has over 14+ years of experience in Web and Application development. He is the author of insightful How-To articles for Code2care.
Follow him on: X
You can also reach out to him via e-mail: rakesh@code2care.org
- Get the current timestamp in Java
- Java Stream with Multiple Filters Example
- Java SE JDBC with Prepared Statement Parameterized Select Example
- Fix: UnsupportedClassVersionError: Unsupported major.minor version 63.0
- [Fix] Java Exception with Lambda - Cannot invoke because object is null
- 7 deadly java.lang.OutOfMemoryError in Java Programming
- How to Calculate the SHA Hash Value of a File in Java
- Java JDBC Connection with Database using SSL (https) URL
- How to Add/Subtract Days to the Current Date in Java
- Create Nested Directories using Java Code
- Spring Boot: JDBCTemplate BatchUpdate Update Query Example
- What is CA FE BA BE 00 00 00 3D in Java Class Bytecode
- Save Java Object as JSON file using Jackson Library
- Adding Custom ASCII Text Banner in Spring Boot Application
- [Fix] Java: Type argument cannot be of primitive type generics
- List of New Features in Java 11 (JEPs)
- Java: How to Add two Maps with example
- Java JDBC Transition Management using PreparedStatement Examples
- Understanding and Handling NullPointerException in Java: Tips and Tricks for Effective Debugging
- Steps of working with Stored Procedures using JDBCTemplate Spring Boot
- Java 8 java.util.Function and BiFunction Examples
- The Motivation Behind Generics in Java Programming
- Get Current Local Date and Time using Java 8 DateTime API
- Java: Convert Char to ASCII
- Deep Dive: Why avoid java.util.Date and Calendar Classes
- Python Program: Use NumPy to generate a random number between 0 and 1 - Python-Programs
- Fix: Eclipse Connection time out: github.com - Eclipse
- MacBook - Time Limit - You have reached your time limit, Ignore Limit - MacOS
- Create Custom Android AlertDialog - Android
- Python: Pandas Rename Columns with List Example - Python
- How to configure PDF iFilter for SharePoint - SharePoint
- Upload Pdf file using PHP Script - PHP
- Align html element at the center of page vertically and horizontally - Html