Rename UnsafeShuffleSpillWriter to UnsafeShuffleExternalSorter

Author: JoshRosen

core/src/main/java/org/apache/spark/shuffle/unsafe/SpillInfo.java

@@ -22,7 +22,7 @@
 import java.io.File;
 
 /**
- * Metadata for a block of data written by {@link UnsafeShuffleSpillWriter}.
+ * Metadata for a block of data written by {@link UnsafeShuffleExternalSorter}.
  */
 final class SpillInfo {
   final long[] partitionLengths;

core/src/main/java/org/apache/spark/shuffle/unsafe/UnsafeShuffleSpillWriter.java renamed to core/src/main/java/org/apache/spark/shuffle/unsafe/UnsafeShuffleExternalSorter.java

@@ -53,9 +53,9 @@
  * spill files. Instead, this merging is performed in {@link UnsafeShuffleWriter}, which uses a
  * specialized merge procedure that avoids extra serialization/deserialization.
  */
-public final class UnsafeShuffleSpillWriter {
+public final class UnsafeShuffleExternalSorter {
 
-  private final Logger logger = LoggerFactory.getLogger(UnsafeShuffleSpillWriter.class);
+  private final Logger logger = LoggerFactory.getLogger(UnsafeShuffleExternalSorter.class);
 
   private static final int SER_BUFFER_SIZE = 1024 * 1024;  // TODO: tune this / don't duplicate
   private static final int PAGE_SIZE = 1024 * 1024;  // TODO: tune this
@@ -86,14 +86,14 @@ public final class UnsafeShuffleSpillWriter {
   private MemoryBlock currentPage = null;
   private long currentPagePosition = -1;
 
-  public UnsafeShuffleSpillWriter(
-      TaskMemoryManager memoryManager,
-      ShuffleMemoryManager shuffleMemoryManager,
-      BlockManager blockManager,
-      TaskContext taskContext,
-      int initialSize,
-      int numPartitions,
-      SparkConf conf) throws IOException {
+  public UnsafeShuffleExternalSorter(
+    TaskMemoryManager memoryManager,
+    ShuffleMemoryManager shuffleMemoryManager,
+    BlockManager blockManager,
+    TaskContext taskContext,
+    int initialSize,
+    int numPartitions,
+    SparkConf conf) throws IOException {
     this.memoryManager = memoryManager;
     this.shuffleMemoryManager = shuffleMemoryManager;
     this.blockManager = blockManager;

core/src/main/java/org/apache/spark/shuffle/unsafe/UnsafeShuffleWriter.java

@@ -118,7 +118,7 @@ private void freeMemory() {
 
   private SpillInfo[] insertRecordsIntoSorter(
       scala.collection.Iterator<? extends Product2<K, V>> records) throws Exception {
-    final UnsafeShuffleSpillWriter sorter = new UnsafeShuffleSpillWriter(
+    final UnsafeShuffleExternalSorter sorter = new UnsafeShuffleExternalSorter(
       memoryManager,
       shuffleMemoryManager,
       blockManager,