HADOOP-15886. Fix findbugs warnings in RegistryDNS.java.

hadoop-common-project/hadoop-registry/dev-support/findbugs-exclude.xml

@@ -0,0 +1,33 @@
+<!--
+   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.
+-->
+<FindBugsFilter>
+  <Match>
+    <Class name="org.apache.hadoop.registry.server.dns.RegistryDNS" />
+    <Method name="addNIOTCP" />
+    <Bug pattern="RV_RETURN_VALUE_IGNORED_BAD_PRACTICE" />
+  </Match>
+  <Match>
+    <Class name="org.apache.hadoop.registry.server.dns.RegistryDNS" />
+    <Method name="addNIOUDP" />
+    <Bug pattern="RV_RETURN_VALUE_IGNORED_BAD_PRACTICE" />
+  </Match>
+  <Match>
+    <Class name="org.apache.hadoop.registry.server.dns.RegistryDNS" />
+    <Method name="serveNIOTCP" />
+    <Bug pattern="RV_RETURN_VALUE_IGNORED_BAD_PRACTICE" />
+  </Match>
+</FindBugsFilter>

hadoop-common-project/hadoop-registry/pom.xml

@@ -162,6 +162,16 @@
       </resource>
     </resources>
     <plugins>
+      <plugin>
+        <groupId>org.codehaus.mojo</groupId>
+        <artifactId>findbugs-maven-plugin</artifactId>
+        <configuration>
+          <findbugsXmlOutput>true</findbugsXmlOutput>
+          <xmlOutput>true</xmlOutput>
+          <excludeFilterFile>${project.basedir}/dev-support/findbugs-exclude.xml</excludeFilterFile>
+          <effort>Max</effort>
+        </configuration>
+      </plugin>
       <plugin>
         <groupId>org.apache.rat</groupId>
         <artifactId>apache-rat-plugin</artifactId>

hadoop-yarn-project/hadoop-yarn/dev-support/findbugs-exclude.xml

@@ -639,22 +639,6 @@
     <Bug pattern="MS_EXPOSE_REP" />
   </Match>
 
-  <Match>
-    <Class name="org.apache.hadoop.registry.server.dns.RegistryDNS" />
-    <Method name="addNIOTCP" />
-    <Bug pattern="RV_RETURN_VALUE_IGNORED_BAD_PRACTICE" />
-  </Match>
-  <Match>
-    <Class name="org.apache.hadoop.registry.server.dns.RegistryDNS" />
-    <Method name="addNIOUDP" />
-    <Bug pattern="RV_RETURN_VALUE_IGNORED_BAD_PRACTICE" />
-  </Match>
-  <Match>
-    <Class name="org.apache.hadoop.registry.server.dns.RegistryDNS" />
-    <Method name="serveNIOTCP" />
-    <Bug pattern="RV_RETURN_VALUE_IGNORED_BAD_PRACTICE" />
-  </Match>
-
   <!-- EQ_OVERRIDING_EQUALS_NOT_SYMMETRIC -->
   <Match>
     <Class name="org.apache.hadoop.yarn.server.nodemanager.containermanager.resourceplugin.gpu.AssignedGpuDevice" />