netty: Add test for AbstractHttp2Headers

This increases line coverage by 1.3%.

netty/src/test/java/io/grpc/netty/AbstractHttp2HeadersTest.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright 2016, Google Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *    * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *    * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *
+ *    * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package io.grpc.netty;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
+
+import com.google.common.base.Defaults;
+
+import io.netty.handler.codec.http2.Http2Headers;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+
+/** Unit tests for {@link AbstractHttp2Headers}. */
+@RunWith(JUnit4.class)
+public class AbstractHttp2HeadersTest {
+  @Test
+  public void allMethodsAreUnsupported() {
+    Http2Headers headers = new AbstractHttp2Headers() {};
+    for (Method method : Http2Headers.class.getMethods()) {
+      // Avoid Java 8 default methods, without requiring Java 8 with isDefault()
+      if (!Modifier.isAbstract(method.getModifiers())) {
+        continue;
+      }
+      Class<?>[] params = method.getParameterTypes();
+      Object[] args = new Object[params.length];
+      for (int i = 0; i < params.length; i++) {
+        args[i] = Defaults.defaultValue(params[i]);
+      }
+      try {
+        method.invoke(headers, args);
+        fail("Expected exception for method: " + method);
+      } catch (InvocationTargetException ex) {
+        assertEquals("For method: " + method,
+            UnsupportedOperationException.class, ex.getCause().getClass());
+      } catch (Throwable t) {
+        throw new RuntimeException("Failure with method: " + method, t);
+      }
+    }
+  }
+}