[SPARK-13579][BUILD] Stop building the main Spark assembly.

This change modifies the "assembly/" module to just copy needed
dependencies to its build directory, and modifies the packaging
script to pick those up (and remove duplicate jars packages in the
examples module).

I also made some minor adjustments to dependencies to remove some
test jars from the final packaging, and remove jars that conflict with each
other when packaged separately (e.g. servlet api).

Also note that this change restores guava in applications' classpaths, even
though it's still shaded inside Spark. This is now needed for the Hadoop
libraries that are packaged with Spark, which now are not processed by
the shade plugin.

Author: Marcelo Vanzin <vanzin@cloudera.com>

Closes #11796 from vanzin/SPARK-13579.

1 files changed, 2 insertions, 2 deletions

diff --git a/core/src/main/scala/org/apache/spark/util/Utils.scala b/core/src/main/scala/org/apache/spark/util/Utils.scala
index 50bcf85805..c304629bcd 100644
--- a/core/src/main/scala/org/apache/spark/util/Utils.scala
+++ b/core/src/main/scala/org/apache/spark/util/Utils.scala
@@ -1121,9 +1121,9 @@ private[spark] object Utils extends Logging {
       extraEnvironment: Map[String, String] = Map.empty,
       redirectStderr: Boolean = true): String = {
     val process = executeCommand(command, workingDir, extraEnvironment, redirectStderr)
-    val output = new StringBuffer
+    val output = new StringBuilder
     val threadName = "read stdout for " + command(0)
-    def appendToOutput(s: String): Unit = output.append(s)
+    def appendToOutput(s: String): Unit = output.append(s).append("\n")
     val stdoutThread = processStreamByLine(threadName, process.getInputStream, appendToOutput)
     val exitCode = process.waitFor()
     stdoutThread.join()   // Wait for it to finish reading output