HDFS-12431. [JDK17] Upgrade JUnit from 4 to 5 in hadoop-hdfs Part4. (#7647)

* HDFS-12431. [JDK17] Upgrade JUnit from 4 to 5 in hadoop-hdfs Part4.

Co-authored-by: Chris Nauroth <cnauroth@apache.org>
Co-authored-by: Shilun Fan <slfan1989@apache.org>
Reviewed-by: Chris Nauroth <cnauroth@apache.org>
Reviewed-by: Shilun Fan <slfan1989@apache.org>
Signed-off-by: Shilun Fan <slfan1989@apache.org>

Author: 3 people

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/tools/TestAdminHelper.java

@@ -17,8 +17,10 @@
  */
 package org.apache.hadoop.hdfs.tools;
 
-import org.junit.Assert;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
  * Test class to test Admin Helper.
@@ -28,11 +30,10 @@ public class TestAdminHelper {
   @Test
   public void prettifyExceptionWithNpe() {
     String pretty = AdminHelper.prettifyException(new NullPointerException());
-    Assert.assertTrue(
+    assertTrue(pretty.startsWith("NullPointerException at org.apache.hadoop.hdfs.tools"
+            + ".TestAdminHelper.prettifyExceptionWithNpe"),
         "Prettified exception message doesn't contain the required exception "
-            + "message",
-        pretty.startsWith("NullPointerException at org.apache.hadoop.hdfs.tools"
-            + ".TestAdminHelper.prettifyExceptionWithNpe"));
+            + "message");
   }
 
   @Test
@@ -42,7 +43,7 @@ public void prettifyException() {
         new IllegalArgumentException("Something is wrong",
             new IllegalArgumentException("Something is illegal")));
 
-    Assert.assertEquals(
+    assertEquals(
         "IllegalArgumentException: Something is wrong",
         pretty);