Unit test for TriggerOnErrorOrWorseLogAppender

sdccc/src/test/java/com/draeger/medical/sdccc/util/TriggerOnErrorOrWorseLogAppenderTest.java

@@ -0,0 +1,67 @@
+/*
+ * This Source Code Form is subject to the terms of the MIT License.
+ * Copyright (c) 2023 Draegerwerk AG & Co. KGaA.
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+package com.draeger.medical.sdccc.util;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+import org.apache.logging.log4j.Level;
+import org.apache.logging.log4j.core.Filter;
+import org.apache.logging.log4j.core.LogEvent;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Unit tests for the {@linkplain TriggerOnErrorOrWorseLogAppender}.
+ */
+public class TriggerOnErrorOrWorseLogAppenderTest {
+
+    /**
+     * Test if the append method handles all Log Levels appropriately.
+     */
+    @Test
+    public void testAppendWithDifferentLogLevels() {
+        testAppend(Level.ALL, false);
+        testAppend(Level.TRACE, false);
+        testAppend(Level.DEBUG, false);
+        testAppend(Level.INFO, false);
+        testAppend(Level.WARN, false);
+        testAppend(Level.ERROR, true);
+        testAppend(Level.FATAL, true);
+        testAppend(Level.OFF, true);
+    }
+
+    /**
+     * Used by the unit test testAppendWithDifferentLogLevels().
+     * @param level the Log Level to test
+     * @param expectHandlerCall true if it is expected that the Handler is called, false otherwise.
+     */
+    private void testAppend(final Level level, final boolean expectHandlerCall) {
+
+        final AtomicBoolean flag = new AtomicBoolean(false);
+
+        // given
+        final Filter filter = mock(Filter.class);
+        final TriggerOnErrorOrWorseLogAppender classUnderTest = new TriggerOnErrorOrWorseLogAppender("log", filter);
+        classUnderTest.setOnErrorOrWorseHandler((LogEvent event) -> flag.set(true));
+        final LogEvent event = mock(LogEvent.class);
+        when(event.getLevel()).thenReturn(level);
+
+        // when
+        classUnderTest.append(event);
+
+        // then
+        if (expectHandlerCall) {
+            assertTrue(flag.get());
+        } else {
+            assertFalse(flag.get());
+        }
+    }
+}