KAFKA-2316: Drop java 1.6 support; patched by Sriharsha Chintalapani reviewed by Ismael Juma and Gwen Shapira

build.gradle

@@ -4,9 +4,9 @@
 // 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.
@@ -74,7 +74,7 @@ subprojects {
   apply plugin: 'maven'
   apply plugin: 'signing'
 
-  sourceCompatibility = 1.6
+  sourceCompatibility = 1.7
 
   uploadArchives {
     repositories {