RATIS-2124. Remove the use of org.junit.After/Rule.

Author: fanshilun

ratis-common/src/test/java/org/apache/ratis/BaseTest.java

@@ -26,16 +26,13 @@
 import org.apache.ratis.util.StringUtils;
 import org.apache.ratis.util.TimeDuration;
 import org.apache.ratis.util.function.CheckedRunnable;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Rule;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Assumptions;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.TestInfo;
 import org.junit.jupiter.api.Timeout;
-import org.junit.rules.TestName;
+import org.junit.jupiter.api.extension.RegisterExtension;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.slf4j.event.Level;
@@ -87,8 +84,7 @@ public void setup(TestInfo testInfo) {
         + "." + (method == null? null : method.getName());
   }
 
-  // @Before annotation is retained to support junit 4 tests.
-  @Before
+  @BeforeEach
   public void checkAssumptions() {
     final int leaks = ReferenceCountedLeakDetector.getLeakDetector().getLeakCount();
     Assumptions.assumeFalse(0 < leaks, () -> "numLeaks " + leaks + " > 0");
@@ -100,8 +96,6 @@ public void checkAssumptions() {
     Assumptions.assumeTrue(exited == null, () -> "Already exited with " + exited);
   }
 
-  // @After annotation is retained to support junit 4 tests.
-  @After
   @AfterEach
   public void assertNoFailures() {
     final Throwable e = firstException.get();
@@ -112,8 +106,7 @@ public void assertNoFailures() {
     ExitUtils.assertNotTerminated();
   }
 
-  // Retained to support junit 4 tests.
-  @Rule
+  @RegisterExtension
   public final TestName testName = new TestName();
 
   private static final Supplier<File> ROOT_TEST_DIR = JavaUtils.memoize(

ratis-common/src/test/java/org/apache/ratis/TestName.java

@@ -0,0 +1,39 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ *  or more contributor license agreements.  See the NOTICE file
+ *  distributed with this work for additional information
+ *  regarding copyright ownership.  The ASF licenses this file
+ *  to you under the Apache License, Version 2.0 (the
+ *  "License"); you may not use this file except in compliance
+ *  with the License.  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package org.apache.ratis;
+
+import org.junit.jupiter.api.extension.BeforeEachCallback;
+import org.junit.jupiter.api.extension.ExtensionContext;
+
+/**
+ * This is a custom JUnit5 `RegisterExtension`
+ * we created to obtain the methond name of the executing function.
+ */
+public class TestName implements BeforeEachCallback {
+
+  private volatile String name;
+
+  @Override
+  public void beforeEach(ExtensionContext extensionContext) throws Exception {
+    name = extensionContext.getTestMethod().get().getName();
+  }
+
+  public String getMethodName() {
+    return this.name;
+  }
+}

ratis-server/src/test/java/org/apache/ratis/statemachine/RaftSnapshotBaseTest.java

@@ -50,10 +50,10 @@
 import org.apache.ratis.util.JavaUtils;
 import org.apache.ratis.util.LifeCycle;
 import org.apache.ratis.util.Slf4jUtils;
-import org.junit.After;
 import org.junit.Assert;
-import org.junit.Before;
 import org.junit.Test;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -124,7 +124,7 @@ public static void assertLogContent(RaftServer.Division server, boolean isLeader
 
   public abstract MiniRaftCluster.Factory<?> getFactory();
 
-  @Before
+  @BeforeEach
   public void setup() throws IOException {
     final RaftProperties prop = new RaftProperties();
     prop.setClass(MiniRaftCluster.STATEMACHINE_CLASS_KEY,
@@ -136,7 +136,7 @@ public void setup() throws IOException {
     cluster.start();
   }
 
-  @After
+  @AfterEach
   public void tearDown() {
     if (cluster != null) {
       cluster.shutdown();