HBASE-22888 Share some stuffs with the initial reader when new stream reader created

hbase-backup/src/main/java/org/apache/hadoop/hbase/backup/util/RestoreTool.java

@@ -436,7 +436,6 @@ byte[][] generateBoundaryKeys(ArrayList<Path> regionDirList) throws IOException
           HFile.Reader reader = HFile.createReader(fs, hfile, conf);
           final byte[] first, last;
           try {
-            reader.loadFileInfo();
             first = reader.getFirstRowKey().get();
             last = reader.getLastRowKey().get();
             LOG.debug("Trying to figure out region boundaries hfile=" + hfile + " first="

hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/HFileInputFormat.java

@@ -91,7 +91,6 @@ public void initialize(InputSplit split, TaskAttemptContext context)
 
       // The file info must be loaded before the scanner can be used.
       // This seems like a bug in HBase, but it's easily worked around.
-      this.in.loadFileInfo();
       this.scanner = in.getScanner(false, false);
 
     }

hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestHFileOutputFormat2.java

@@ -401,7 +401,7 @@ public void test_TIMERANGE() throws Exception {
       // open as HFile Reader and pull out TIMERANGE FileInfo.
       HFile.Reader rd =
           HFile.createReader(fs, file[0].getPath(), new CacheConfig(conf), true, conf);
-      Map<byte[],byte[]> finfo = rd.loadFileInfo();
+      Map<byte[],byte[]> finfo = rd.getHFileInfo();
       byte[] range = finfo.get(Bytes.toBytes("TIMERANGE"));
       assertNotNull(range);
 
@@ -1188,7 +1188,7 @@ public void testColumnFamilySettings() throws Exception {
         // compression
         Path dataFilePath = fs.listStatus(f.getPath())[0].getPath();
         Reader reader = HFile.createReader(fs, dataFilePath, new CacheConfig(conf), true, conf);
-        Map<byte[], byte[]> fileInfo = reader.loadFileInfo();
+        Map<byte[], byte[]> fileInfo = reader.getHFileInfo();
 
         byte[] bloomFilter = fileInfo.get(BLOOM_FILTER_TYPE_KEY);
         if (bloomFilter == null) bloomFilter = Bytes.toBytes("NONE");
@@ -1601,7 +1601,8 @@ public void TestConfigureCompression() throws Exception {
         LocatedFileStatus keyFileStatus = iterator.next();
         HFile.Reader reader =
             HFile.createReader(fs, keyFileStatus.getPath(), new CacheConfig(conf), true, conf);
-        assertEquals(reader.getCompressionAlgorithm().getName(), hfileoutputformatCompression);
+        assertEquals(reader.getTrailer().getCompressionCodec().getName(),
+            hfileoutputformatCompression);
       }
     } finally {
       if (writer != null && context != null) {

hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestImportTSVWithVisibilityLabels.java

@@ -484,7 +484,6 @@ private static void validateTable(Configuration conf, TableName tableName, Strin
   private static int getKVCountFromHfile(FileSystem fs, Path p) throws IOException {
     Configuration conf = util.getConfiguration();
     HFile.Reader reader = HFile.createReader(fs, p, new CacheConfig(conf), true, conf);
-    reader.loadFileInfo();
     HFileScanner scanner = reader.getScanner(false, false);
     scanner.seekTo();
     int count = 0;

hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestImportTsv.java

@@ -561,7 +561,6 @@ private static void validateHFiles(FileSystem fs, String outputPath, String fami
   private static int getKVCountFromHfile(FileSystem fs, Path p) throws IOException {
     Configuration conf = util.getConfiguration();
     HFile.Reader reader = HFile.createReader(fs, p, new CacheConfig(conf), true, conf);
-    reader.loadFileInfo();
     HFileScanner scanner = reader.getScanner(false, false);
     scanner.seekTo();
     int count = 0;

hbase-server/src/main/java/org/apache/hadoop/hbase/io/HalfStoreFileReader.java

@@ -23,21 +23,21 @@
 import java.util.Optional;
 import java.util.concurrent.atomic.AtomicInteger;
 
-import org.apache.yetus.audience.InterfaceAudience;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.fs.FileSystem;
-import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.HConstants;
-import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.KeyValue;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.client.Scan;
 import org.apache.hadoop.hbase.io.hfile.CacheConfig;
+import org.apache.hadoop.hbase.io.hfile.HFileInfo;
 import org.apache.hadoop.hbase.io.hfile.HFileScanner;
+import org.apache.hadoop.hbase.io.hfile.ReaderContext;
 import org.apache.hadoop.hbase.regionserver.StoreFileReader;
 import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.yetus.audience.InterfaceAudience;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * A facade for a {@link org.apache.hadoop.hbase.io.hfile.HFile.Reader} that serves up
@@ -66,45 +66,19 @@ public class HalfStoreFileReader extends StoreFileReader {
 
   private boolean firstKeySeeked = false;
 
-  /**
-   * Creates a half file reader for a normal hfile.
-   * @param fs fileystem to read from
-   * @param p path to hfile
-   * @param cacheConf
-   * @param r original reference file (contains top or bottom)
-   * @param conf Configuration
-   * @throws IOException
-   */
-  public HalfStoreFileReader(FileSystem fs, Path p, CacheConfig cacheConf, Reference r,
-      boolean isPrimaryReplicaStoreFile, AtomicInteger refCount, boolean shared, Configuration conf)
-      throws IOException {
-    super(fs, p, cacheConf, isPrimaryReplicaStoreFile, refCount, shared, conf);
-    // This is not actual midkey for this half-file; its just border
-    // around which we split top and bottom.  Have to look in files to find
-    // actual last and first keys for bottom and top halves.  Half-files don't
-    // have an actual midkey themselves. No midkey is how we indicate file is
-    // not splittable.
-    this.splitkey = r.getSplitKey();
-    this.splitCell = new KeyValue.KeyOnlyKeyValue(this.splitkey, 0, this.splitkey.length);
-    // Is it top or bottom half?
-    this.top = Reference.isTopFileRegion(r.getFileRegion());
-  }
-
   /**
    * Creates a half file reader for a hfile referred to by an hfilelink.
-   * @param fs fileystem to read from
-   * @param p path to hfile
-   * @param in {@link FSDataInputStreamWrapper}
-   * @param size Full size of the hfile file
-   * @param cacheConf
+   * @param context Reader context info
+   * @param fileInfo HFile info
+   * @param cacheConf CacheConfig
    * @param r original reference file (contains top or bottom)
+   * @param refCount reference count
    * @param conf Configuration
-   * @throws IOException
    */
-  public HalfStoreFileReader(final FileSystem fs, final Path p, final FSDataInputStreamWrapper in,
-      long size, final CacheConfig cacheConf, final Reference r, boolean isPrimaryReplicaStoreFile,
-      AtomicInteger refCount, boolean shared, final Configuration conf) throws IOException {
-    super(fs, p, in, size, cacheConf, isPrimaryReplicaStoreFile, refCount, shared, conf);
+  public HalfStoreFileReader(final ReaderContext context, final HFileInfo fileInfo,
+      final CacheConfig cacheConf, final Reference r,
+      AtomicInteger refCount, final Configuration conf) throws IOException {
+    super(context, fileInfo, cacheConf, refCount, conf);
     // This is not actual midkey for this half-file; its just border
     // around which we split top and bottom.  Have to look in files to find
     // actual last and first keys for bottom and top halves.  Half-files don't