SPARK-4682 [CORE] Consolidate various 'Clock' classes

Another one from JoshRosen 's wish list. The first commit is much smaller and removes 2 of the 4 Clock classes. The second is much larger, necessary for consolidating the streaming one. I put together implementations in the way that seemed simplest. Almost all the change is standardizing class and method names.

Author: Sean Owen <sowen@cloudera.com>

Closes #4514 from srowen/SPARK-4682 and squashes the following commits:

5ed3a03 [Sean Owen] Javadoc Clock classes; make ManualClock private[spark]
169dd13 [Sean Owen] Add support for legacy org.apache.spark.streaming clock class names
277785a [Sean Owen] Reduce the net change in this patch by reversing some unnecessary syntax changes along the way
b5e53df [Sean Owen] FakeClock -> ManualClock; getTime() -> getTimeMillis()
160863a [Sean Owen] Consolidate Streaming Clock class into common util Clock
7c956b2 [Sean Owen] Consolidate Clocks except for Streaming Clock

(cherry picked from commit 34b7c35380c88569a1396fb4ed991a0bed4288e7)
Signed-off-by: Andrew Or <andrew@databricks.com>

2 files changed, 2 insertions, 2 deletions

diff --git a/mllib/src/test/java/org/apache/spark/ml/classification/JavaStreamingLogisticRegressionSuite.java b/mllib/src/test/java/org/apache/spark/ml/classification/JavaStreamingLogisticRegressionSuite.java
index ac945ba6f2..640d2ec55e 100644
--- a/mllib/src/test/java/org/apache/spark/ml/classification/JavaStreamingLogisticRegressionSuite.java
+++ b/mllib/src/test/java/org/apache/spark/ml/classification/JavaStreamingLogisticRegressionSuite.java
@@ -47,7 +47,7 @@ public class JavaStreamingLogisticRegressionSuite implements Serializable {
     SparkConf conf = new SparkConf()
       .setMaster("local[2]")
       .setAppName("test")
-      .set("spark.streaming.clock", "org.apache.spark.streaming.util.ManualClock");
+      .set("spark.streaming.clock", "org.apache.spark.util.ManualClock");
     ssc = new JavaStreamingContext(conf, new Duration(1000));
     ssc.checkpoint("checkpoint");
   }
diff --git a/mllib/src/test/java/org/apache/spark/mllib/regression/JavaStreamingLinearRegressionSuite.java b/mllib/src/test/java/org/apache/spark/mllib/regression/JavaStreamingLinearRegressionSuite.java
index a4dd1ac39a..899c4ea607 100644
--- a/mllib/src/test/java/org/apache/spark/mllib/regression/JavaStreamingLinearRegressionSuite.java
+++ b/mllib/src/test/java/org/apache/spark/mllib/regression/JavaStreamingLinearRegressionSuite.java
@@ -45,7 +45,7 @@ public class JavaStreamingLinearRegressionSuite implements Serializable {
     SparkConf conf = new SparkConf()
       .setMaster("local[2]")
       .setAppName("test")
-      .set("spark.streaming.clock", "org.apache.spark.streaming.util.ManualClock");
+      .set("spark.streaming.clock", "org.apache.spark.util.ManualClock");
     ssc = new JavaStreamingContext(conf, new Duration(1000));
     ssc.checkpoint("checkpoint");
   }