HADOOP-9279. Merging change r1449543 from trunk

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1449544 13f79535-47bb-0310-9956-ffa450edef68

BUILDING.txt

@@ -87,6 +87,33 @@ Maven build goals:
   * -Dtest.exclude=<TESTCLASSNAME>
   * -Dtest.exclude.pattern=**/<TESTCLASSNAME1>.java,**/<TESTCLASSNAME2>.java
 
+----------------------------------------------------------------------------------
+Building components separately
+
+If you are building a submodule directory, all the hadoop dependencies this
+submodule has will be resolved as all other 3rd party dependencies. This is,
+from the Maven cache or from a Maven repository (if not available in the cache
+or the SNAPSHOT 'timed out').
+An alternative is to run 'mvn install -DskipTests' from Hadoop source top
+level once; and then work from the submodule. Keep in mind that SNAPSHOTs
+time out after a while, using the Maven '-nsu' will stop Maven from trying
+to update SNAPSHOTs from external repos.
+
+----------------------------------------------------------------------------------
+Importing projects to eclipse
+
+When you import the project to eclipse, install hadoop-maven-plugins at first.
+
+  $ cd hadoop-maven-plugins
+  $ mvn install
+
+Then, generate ecplise project files.
+
+  $ mvn eclipse:eclipse -DskipTests
+
+At last, import to eclipse by specifying the root directory of the project via
+[File] > [Import] > [Existing Projects into Workspace].
+
 ----------------------------------------------------------------------------------
 Building distributions:
 

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -18,6 +18,9 @@ Release 2.0.4-beta - UNRELEASED
 
     HADOOP-9117. replace protoc ant plugin exec with a maven plugin. (tucu)
 
+    HADOOP-9279. Document the need to build hadoop-maven-plugins for
+    eclipse and separate project builds. (Tsuyoshi Ozawa via suresh)
+
   OPTIMIZATIONS
 
   BUG FIXES