SPARK-3794 [CORE] Building spark core fails due to inadvertent dependency on Commons IO

Remove references to Commons IO FileUtils and replace with pure Java version, which doesn't need to traverse the whole directory tree first.

I think this method could be refined further if it would be alright to rename it and its args and break it down into two methods. I'm starting with a simple recursive rendition.

Author: Sean Owen <sowen@cloudera.com>

Closes #2662 from srowen/SPARK-3794 and squashes the following commits:

4cd172f [Sean Owen] Remove references to Commons IO FileUtils and replace with pure Java version, which doesn't need to traverse the whole directory tree first

2 files changed, 10 insertions, 11 deletions

diff --git a/core/src/main/scala/org/apache/spark/deploy/worker/Worker.scala b/core/src/main/scala/org/apache/spark/deploy/worker/Worker.scala
index 3b13f43a18..9b52cb06fb 100755
--- a/core/src/main/scala/org/apache/spark/deploy/worker/Worker.scala
+++ b/core/src/main/scala/org/apache/spark/deploy/worker/Worker.scala
@@ -29,7 +29,6 @@ import scala.language.postfixOps
 
 import akka.actor._
 import akka.remote.{DisassociatedEvent, RemotingLifecycleEvent}
-import org.apache.commons.io.FileUtils
 
 import org.apache.spark.{Logging, SecurityManager, SparkConf, SparkException}
 import org.apache.spark.deploy.{ExecutorDescription, ExecutorState}
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 a67124140f..3d307b3c16 100644
--- a/core/src/main/scala/org/apache/spark/util/Utils.scala
+++ b/core/src/main/scala/org/apache/spark/util/Utils.scala
@@ -35,8 +35,6 @@ import scala.util.control.{ControlThrowable, NonFatal}
 
 import com.google.common.io.Files
 import com.google.common.util.concurrent.ThreadFactoryBuilder
-import org.apache.commons.io.FileUtils
-import org.apache.commons.io.filefilter.TrueFileFilter
 import org.apache.commons.lang3.SystemUtils
 import org.apache.hadoop.conf.Configuration
 import org.apache.log4j.PropertyConfigurator
@@ -710,18 +708,20 @@ private[spark] object Utils extends Logging {
    * Determines if a directory contains any files newer than cutoff seconds.
    * 
    * @param dir must be the path to a directory, or IllegalArgumentException is thrown
-   * @param cutoff measured in seconds. Returns true if there are any files in dir newer than this.
+   * @param cutoff measured in seconds. Returns true if there are any files or directories in the
+   *               given directory whose last modified time is later than this many seconds ago
    */
   def doesDirectoryContainAnyNewFiles(dir: File, cutoff: Long): Boolean = {
-    val currentTimeMillis = System.currentTimeMillis
     if (!dir.isDirectory) {
-      throw new IllegalArgumentException (dir + " is not a directory!")
-    } else {
-      val files = FileUtils.listFilesAndDirs(dir, TrueFileFilter.TRUE, TrueFileFilter.TRUE)
-      val cutoffTimeInMillis = (currentTimeMillis - (cutoff * 1000))
-      val newFiles = files.filter { _.lastModified > cutoffTimeInMillis }
-      newFiles.nonEmpty
+      throw new IllegalArgumentException("$dir is not a directory!")
     }
+    val filesAndDirs = dir.listFiles()
+    val cutoffTimeInMillis = System.currentTimeMillis - (cutoff * 1000)
+
+    filesAndDirs.exists(_.lastModified() > cutoffTimeInMillis) ||
+    filesAndDirs.filter(_.isDirectory).exists(
+      subdir => doesDirectoryContainAnyNewFiles(subdir, cutoff)
+    )
   }
 
   /**