diff --git a/BUILDING.txt b/BUILDING.txt index 77561c5546fd3..a98d7049a2b0b 100644 --- a/BUILDING.txt +++ b/BUILDING.txt @@ -315,12 +315,12 @@ Controlling the redistribution of the protobuf-2.5 dependency The protobuf 2.5.0 library is used at compile time to compile the class org.apache.hadoop.ipc.ProtobufHelper; this class known to have been used by - external projects in the past. Protobuf 2.5 is not used elsewhere in + external projects in the past. Protobuf 2.5 is not used directly in the Hadoop codebase; alongside the move to Protobuf 3.x a private successor class, org.apache.hadoop.ipc.internal.ShadedProtobufHelper is now used. The hadoop-common module no longer exports its compile-time dependency on - protobuf-2.5. Hadoop distributions no longer include it. + protobuf-java-2.5. Any application declaring a dependency on hadoop-commmon will no longer get the artifact added to their classpath. If is still required, then they must explicitly declare it: @@ -337,10 +337,14 @@ Controlling the redistribution of the protobuf-2.5 dependency -Dcommon.protobuf2.scope=compile - If this is done then protobuf-2.5.0.jar will again be exported as a + If this is done then protobuf-java-2.5.0.jar will again be exported as a hadoop-common dependency, and included in the share/hadoop/common/lib/ directory of any Hadoop distribution built. + Note that protobuf-java-2.5.0.jar is still placed in + share/hadoop/yarn/timelineservice/lib; this is needed by the hbase client + library. + ---------------------------------------------------------------------------------- Building components separately