diff --git a/core/src/main/scala/org/apache/spark/network/SecurityMessage.scala b/core/src/main/scala/org/apache/spark/network/SecurityMessage.scala
index a1dfc4094cca73885b6c1e7bddec9500919986af..9af9e2e8e9e5995c331bccaf5965155c86295a18 100644
--- a/core/src/main/scala/org/apache/spark/network/SecurityMessage.scala
+++ b/core/src/main/scala/org/apache/spark/network/SecurityMessage.scala
@@ -106,7 +106,6 @@ private[spark] class SecurityMessage() extends Logging {
    * @return BufferMessage
    */
   def toBufferMessage: BufferMessage = {
-    val startTime = System.currentTimeMillis
     val buffers = new ArrayBuffer[ByteBuffer]()
 
     // 4 bytes for the length of the connectionId
diff --git a/core/src/main/scala/org/apache/spark/partial/GroupedMeanEvaluator.scala b/core/src/main/scala/org/apache/spark/partial/GroupedMeanEvaluator.scala
index b5111891ed35b1b74fdb39e656cf6fbbeb8bb217..af26c3d59ac025814bbf63edaa5b42647a9d77ed 100644
--- a/core/src/main/scala/org/apache/spark/partial/GroupedMeanEvaluator.scala
+++ b/core/src/main/scala/org/apache/spark/partial/GroupedMeanEvaluator.scala
@@ -61,7 +61,6 @@ private[spark] class GroupedMeanEvaluator[T](totalOutputs: Int, confidence: Doub
     } else if (outputsMerged == 0) {
       new HashMap[T, BoundedDouble]
     } else {
-      val p = outputsMerged.toDouble / totalOutputs
       val studentTCacher = new StudentTCacher(confidence)
       val result = new JHashMap[T, BoundedDouble](sums.size)
       val iter = sums.entrySet.iterator()
diff --git a/core/src/main/scala/org/apache/spark/storage/BlockFetcherIterator.scala b/core/src/main/scala/org/apache/spark/storage/BlockFetcherIterator.scala
index a02dd9441d67943489cf6e92e291dfb203da5ad0..408a79708805937a35c6cf7ce6f6614eb96acca7 100644
--- a/core/src/main/scala/org/apache/spark/storage/BlockFetcherIterator.scala
+++ b/core/src/main/scala/org/apache/spark/storage/BlockFetcherIterator.scala
@@ -118,11 +118,9 @@ object BlockFetcherIterator {
       })
       bytesInFlight += req.size
       val sizeMap = req.blocks.toMap  // so we can look up the size of each blockID
-      val fetchStart = System.currentTimeMillis()
       val future = connectionManager.sendMessageReliably(cmId, blockMessageArray.toBufferMessage)
       future.onSuccess {
         case Some(message) => {
-          val fetchDone = System.currentTimeMillis()
           val bufferMessage = message.asInstanceOf[BufferMessage]
           val blockMessageArray = BlockMessageArray.fromBufferMessage(bufferMessage)
           for (blockMessage <- blockMessageArray) {
diff --git a/core/src/main/scala/org/apache/spark/util/random/XORShiftRandom.scala b/core/src/main/scala/org/apache/spark/util/random/XORShiftRandom.scala
index 7f220383f9f8bbc3ab9cf1a6c81e3401a64ed82a..55b5713706178fdd074782a9f3d369869b64f2df 100644
--- a/core/src/main/scala/org/apache/spark/util/random/XORShiftRandom.scala
+++ b/core/src/main/scala/org/apache/spark/util/random/XORShiftRandom.scala
@@ -91,7 +91,7 @@ private[spark] object XORShiftRandom {
     val xorRand = new XORShiftRandom(seed)
 
     // this is just to warm up the JIT - we're not timing anything
-    timeIt(1e6.toInt) {
+    timeIt(million) {
       javaRand.nextInt()
       xorRand.nextInt()
     }
diff --git a/examples/src/main/java/org/apache/spark/examples/JavaLogQuery.java b/examples/src/main/java/org/apache/spark/examples/JavaLogQuery.java
index 2a4278d3c30e50a276e2d62aeff4766c769a6f5e..3f7a879538016e97160e0aff98ae75ade11a2530 100644
--- a/examples/src/main/java/org/apache/spark/examples/JavaLogQuery.java
+++ b/examples/src/main/java/org/apache/spark/examples/JavaLogQuery.java
@@ -75,7 +75,6 @@ public final class JavaLogQuery {
 
   public static Tuple3<String, String, String> extractKey(String line) {
     Matcher m = apacheLogRegex.matcher(line);
-    List<String> key = Collections.emptyList();
     if (m.find()) {
       String ip = m.group(1);
       String user = m.group(3);
diff --git a/examples/src/main/java/org/apache/spark/examples/JavaTC.java b/examples/src/main/java/org/apache/spark/examples/JavaTC.java
index 1d776940f06c6583947a4aec8706b4a4ab24ee85..d66b9ba265fe8da2f2443f97aadb61e89e8f6de5 100644
--- a/examples/src/main/java/org/apache/spark/examples/JavaTC.java
+++ b/examples/src/main/java/org/apache/spark/examples/JavaTC.java
@@ -85,7 +85,7 @@ public final class JavaTC {
         }
     });
 
-    long oldCount = 0;
+    long oldCount;
     long nextCount = tc.count();
     do {
       oldCount = nextCount;
diff --git a/examples/src/main/java/org/apache/spark/examples/sql/JavaSparkSQL.java b/examples/src/main/java/org/apache/spark/examples/sql/JavaSparkSQL.java
index b5b438e9753a779076ecf3e0ee974ac54cad06c5..d62a72f53443ce69d01f12a4239247aee8c541fa 100644
--- a/examples/src/main/java/org/apache/spark/examples/sql/JavaSparkSQL.java
+++ b/examples/src/main/java/org/apache/spark/examples/sql/JavaSparkSQL.java
@@ -23,7 +23,6 @@ import java.util.List;
 import org.apache.spark.api.java.JavaRDD;
 import org.apache.spark.api.java.JavaSparkContext;
 import org.apache.spark.api.java.function.Function;
-import org.apache.spark.api.java.function.VoidFunction;
 
 import org.apache.spark.sql.api.java.JavaSQLContext;
 import org.apache.spark.sql.api.java.JavaSchemaRDD;