JUnit 5 assertNotSame Example

JUnit 5 Tutorial

In this article, we will learn about assertNotSame() static method which belongs to JUnit 5 org.junit.jupiter.api.Assertions Class. Note that in JUnit 5 all JUnit 4 assertion methods are moved to org.junit.jupiter.api.Assertions class.

There are many overloaded version of assertNotSame() methods present in org.junit.jupiter.api.Assertions class.

Let me list out tools and technologies that I have used to develop JUnit 5 assertNotSame Example.

Tools and Technologies Used

Eclipse photon (only this eclipse version supports JUnit 5)
Maven
JUnit 5
JDK 8 or late

assertNotSame(Object unexpected, Object actual) method asserts that two objects do not refer to the same object. If they do refer to the same object, an AssertionError without a message is thrown.

assertNotSame() Method Example

import static org.junit.Assert.assertNotSame;

import java.util.HashMap;
import java.util.Map;

import org.junit.jupiter.api.Test;

public class JUnit5AssertNotSameExample {
 private String processMap(final String key) {
  final Map<String, String> map = new HashMap<>();
  map.put("key1", "value1");
  map.put("key2", "value2");
  map.put("key3", "value3");
  map.put("key4", "value4");
  map.put("key5", "value5");
  map.put("key6", "value6");
  map.put("key7", "value7");
  map.put("key8", "value8");
  return map.get(key);
 }

 @Test
 public void checkSameReferenceTest() {
  final JUnit5AssertNotSameExample example = new JUnit5AssertNotSameExample();
  assertNotSame(example.processMap("key1"), example.processMap("key2"));
 }
}