KAFKA-16413: add FileLockTest

core/src/test/java/kafka/utils/FileLockTest.java

@@ -0,0 +1,97 @@
+/*
+ * 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 kafka.utils;
+
+import org.junit.jupiter.api.Test;
+
+import java.io.File;
+import java.nio.channels.OverlappingFileLockException;
+
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class FileLockTest {
+    @Test
+    void testLock() {
+        File tempFile = TestUtils.tempFile();
+        FileLock lock1 = new FileLock(tempFile);
+        try {
+            lock1.lock();
+            assertThrows(OverlappingFileLockException.class, lock1::lock);
+
+            FileLock lock2 = new FileLock(tempFile);
+            assertThrows(OverlappingFileLockException.class, lock2::lock);
+            assertFalse(lock2.tryLock());
+            lock1.unlock();
+        } finally {
+            lock1.destroy();
+        }
+    }
+
+    @Test
+    void testTryLock() {
+        File tempFile = TestUtils.tempFile();
+        FileLock lock1 = new FileLock(tempFile);
+        try {
+            assertTrue(lock1.tryLock());
+            assertFalse(lock1.tryLock());
+
+            FileLock lock2 = new FileLock(tempFile);
+            assertFalse(lock2.tryLock());
+            assertThrows(OverlappingFileLockException.class, lock2::lock);
+            lock1.unlock();
+        } finally {
+            lock1.destroy();
+        }
+    }
+
+    @Test
+    void testUnlock() {
+        File tempFile = TestUtils.tempFile();
+        FileLock lock1 = new FileLock(tempFile);
+        try {
+            lock1.lock();
+            lock1.unlock();
+            lock1.lock();
+            lock1.unlock();
+
+            assertTrue(lock1.tryLock());
+            lock1.unlock();
+            assertTrue(lock1.tryLock());
+            lock1.unlock();
+
+            FileLock lock2 = new FileLock(tempFile);
+            assertTrue(lock2.tryLock());
+            lock2.unlock();
+            assertDoesNotThrow(lock2::lock);
+            lock2.unlock();
+        } finally {
+            lock1.destroy();
+        }
+    }
+
+    @Test
+    void testDestroy() {
+        File tempFile = TestUtils.tempFile();
+        FileLock lock1 = new FileLock(tempFile);
+        lock1.destroy();
+        assertFalse(tempFile.exists());
+        assertDoesNotThrow(lock1::destroy);
+    }
+}