update to Guava 20

java/pom.xml

@@ -82,7 +82,7 @@
       <dependency>
         <groupId>com.google.guava</groupId>
         <artifactId>guava</artifactId>
-        <version>19.0</version>
+        <version>20.0</version>
       </dependency>
     </dependencies>
   </dependencyManagement>