Add some changes

testing-modules/junit-5/src/main/java/com/baeldung/junit5/nonstatic/BeforeAfterAllNonStaticTest.java

@@ -0,0 +1,25 @@
+package com.baeldung.junit5.nonstatic;
+
+import org.junit.jupiter.api.*;
+
+@TestInstance(TestInstance.Lifecycle.PER_CLASS)
+public class BeforeAfterAllNonStaticTest {
+
+    String input;
+    Long result;
+
+    @BeforeAll
+    public void setup() {
+        input = "77";
+    }
+
+    @AfterAll
+    public void teardown() {
+        Assertions.assertEquals(77l, result);
+    }
+
+    @Test
+    public void testConvertStringToLong() {
+        result = Long.valueOf(input);
+    }
+}