make store utils avaliable for general store file

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StoreFile.java

@@ -135,4 +135,9 @@ public interface StoreFile {
    * Get the max timestamp of all the cells in the store file.
    */
   OptionalLong getMaximumTimestamp();
+
+  /**
+   * Get the reader for this store file
+   */
+  StoreFileReader getReader();
 }

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StoreUtils.java

@@ -42,25 +42,25 @@ public class StoreUtils {
   /**
    * Creates a deterministic hash code for store file collection.
    */
-  public static OptionalInt getDeterministicRandomSeed(Collection<HStoreFile> files) {
+  public static OptionalInt getDeterministicRandomSeed(Collection<? extends StoreFile> files) {
     return files.stream().mapToInt(f -> f.getPath().getName().hashCode()).findFirst();
   }
 
   /**
    * Determines whether any files in the collection are references.
    * @param files The files.
    */
-  public static boolean hasReferences(Collection<HStoreFile> files) {
+  public static boolean hasReferences(Collection<? extends StoreFile> files) {
     // TODO: make sure that we won't pass null here in the future.
-    return files != null ? files.stream().anyMatch(HStoreFile::isReference) : false;
+    return files != null ? files.stream().anyMatch(sf -> sf.isReference()) : false;
   }
 
   /**
    * Gets lowest timestamp from candidate StoreFiles
    */
-  public static long getLowestTimestamp(Collection<HStoreFile> candidates) throws IOException {
+  public static long getLowestTimestamp(Collection<? extends StoreFile> candidates) throws IOException {
     long minTs = Long.MAX_VALUE;
-    for (HStoreFile storeFile : candidates) {
+    for (StoreFile storeFile : candidates) {
       minTs = Math.min(minTs, storeFile.getModificationTimestamp());
     }
     return minTs;
@@ -71,7 +71,7 @@ public static long getLowestTimestamp(Collection<HStoreFile> candidates) throws
    * @param candidates The files to choose from.
    * @return The largest file; null if no file has a reader.
    */
-  static Optional<HStoreFile> getLargestFile(Collection<HStoreFile> candidates) {
+  static Optional<? extends StoreFile> getLargestFile(Collection<? extends StoreFile> candidates) {
     return candidates.stream().filter(f -> f.getReader() != null)
         .max((f1, f2) -> Long.compare(f1.getReader().length(), f2.getReader().length()));
   }
@@ -81,16 +81,16 @@ static Optional<HStoreFile> getLargestFile(Collection<HStoreFile> candidates) {
    * were created by a mapreduce bulk load are ignored, as they do not correspond to any specific
    * put operation, and thus do not have a memstoreTS associated with them.
    */
-  public static OptionalLong getMaxMemStoreTSInList(Collection<HStoreFile> sfs) {
-    return sfs.stream().filter(sf -> !sf.isBulkLoadResult()).mapToLong(HStoreFile::getMaxMemStoreTS)
+  public static OptionalLong getMaxMemStoreTSInList(Collection<? extends StoreFile> sfs) {
+    return sfs.stream().filter(sf -> !sf.isBulkLoadResult()).mapToLong(sf -> sf.getMaxMemStoreTS())
         .max();
   }
 
   /**
    * Return the highest sequence ID found across all storefiles in the given list.
    */
-  public static OptionalLong getMaxSequenceIdInList(Collection<HStoreFile> sfs) {
-    return sfs.stream().mapToLong(HStoreFile::getMaxSequenceId).max();
+  public static OptionalLong getMaxSequenceIdInList(Collection<? extends StoreFile> sfs) {
+    return sfs.stream().mapToLong(sf -> sf.getMaxSequenceId()).max();
   }
 
   /**
@@ -99,7 +99,7 @@ public static OptionalLong getMaxSequenceIdInList(Collection<HStoreFile> sfs) {
    * @param comparator Comparator used to compare KVs.
    * @return The split point row, or null if splitting is not possible, or reader is null.
    */
-  static Optional<byte[]> getFileSplitPoint(HStoreFile file, CellComparator comparator)
+  static Optional<byte[]> getFileSplitPoint(StoreFile file, CellComparator comparator)
       throws IOException {
     StoreFileReader reader = file.getReader();
     if (reader == null) {
@@ -130,9 +130,9 @@ static Optional<byte[]> getFileSplitPoint(HStoreFile file, CellComparator compar
   /**
    * Gets the mid point of the largest file passed in as split point.
    */
-  static Optional<byte[]> getSplitPoint(Collection<HStoreFile> storefiles,
+  static Optional<byte[]> getSplitPoint(Collection<? extends StoreFile> storefiles,
       CellComparator comparator) throws IOException {
-    Optional<HStoreFile> largestFile = StoreUtils.getLargestFile(storefiles);
+    Optional<? extends StoreFile> largestFile = StoreUtils.getLargestFile(storefiles);
     return largestFile.isPresent() ? StoreUtils.getFileSplitPoint(largestFile.get(), comparator)
         : Optional.empty();
   }