Slight refactoring to SparkContext functions

core/src/main/scala/spark/SparkContext.scala

@@ -581,10 +581,17 @@ class SparkContext(
    *  Return pools for fair scheduler
    *  TODO(xiajunluan): We should take nested pools into account
    */
-  def getPools: ArrayBuffer[Schedulable] = {
+  def getAllPools: ArrayBuffer[Schedulable] = {
     taskScheduler.rootPool.schedulableQueue
   }
 
+  /**
+   * Return the pool associated with the given name, if one exists
+   */
+  def getPoolForName(pool: String): Option[Schedulable] = {
+    taskScheduler.rootPool.schedulableNameToSchedulable.get(pool)
+  }
+
   /**
    *  Return current scheduling mode
    */
@@ -592,10 +599,6 @@ class SparkContext(
     taskScheduler.schedulingMode
   }
 
-  def getPoolNameToPool: HashMap[String, Schedulable] = {
-    taskScheduler.rootPool.schedulableNameToSchedulable
-  }
-
   /**
    * Clear the job's list of files added by `addFile` so that they do not get downloaded to
    * any new nodes.

core/src/main/scala/spark/ui/jobs/PoolTable.scala

@@ -38,7 +38,7 @@ private[spark] class FIFOSource() extends PoolSource {
  */
 private[spark] class FairSource(sc: SparkContext) extends PoolSource {
   def getPools: Seq[Schedulable] = {
-    sc.getPools.toSeq
+    sc.getAllPools.toSeq
   }
 }
 
@@ -48,7 +48,7 @@ private[spark] class FairSource(sc: SparkContext) extends PoolSource {
 private[spark] class PoolDetailSource(sc: SparkContext, poolName: String) extends PoolSource {
   def getPools: Seq[Schedulable] = {
     val pools = HashSet[Schedulable]()
-    pools += sc.getPoolNameToPool(poolName)
+    pools += sc.getPoolForName(poolName).get
     pools.toSeq
   }
 }