Add findbugs exclude filter.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/collections/trunk@1435977 13f79535-47bb-0310-9956-ffa450edef68

findbugs-exclude-filter.xml

@@ -0,0 +1,33 @@
+<?xml version="1.0"?>
+<!--
+   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.
+-->
+
+<!--
+  This file contains some false positive bugs detected by findbugs. Their
+  false positive nature has been analyzed individually and they have been
+  put here to instruct findbugs it must ignore them.
+-->
+<FindBugsFilter>
+
+  <!--  explicit return of a null value for type Boolean is intended -->
+  <Match>
+    <Class name="org.apache.commons.collections.MapUtils" />
+    <Method name="getBoolean" params="java.util.Map, java.lang.Object" returns="java.lang.Boolean" />
+    <Bug pattern="NP_BOOLEAN_RETURN_NULL" />
+  </Match>
+
+</FindBugsFilter>

pom.xml

@@ -505,6 +505,7 @@
         <configuration>
           <threshold>Normal</threshold>
           <effort>Default</effort>
+          <excludeFilterFile>${basedir}/findbugs-exclude-filter.xml</excludeFilterFile>
        </configuration>
       </plugin>
       <plugin>