Extractor cleanup

- Align class summary Javadoc
- Fix ErrorProne + Style warnings

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=177165593

library/core/src/main/java/com/google/android/exoplayer2/extractor/flv/FlvExtractor.java

@@ -15,6 +15,7 @@
  */
 package com.google.android.exoplayer2.extractor.flv;
 
+import android.support.annotation.IntDef;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.extractor.Extractor;
 import com.google.android.exoplayer2.extractor.ExtractorInput;
@@ -25,9 +26,11 @@ import com.google.android.exoplayer2.extractor.SeekMap;
 import com.google.android.exoplayer2.util.ParsableByteArray;
 import com.google.android.exoplayer2.util.Util;
 import java.io.IOException;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
 
 /**
- * Facilitates the extraction of data from the FLV container format.
+ * Extracts data from the FLV container format.
  */
 public final class FlvExtractor implements Extractor, SeekMap {
 
@@ -43,16 +46,22 @@ public final class FlvExtractor implements Extractor, SeekMap {
 
   };
 
-  // Header sizes.
+  /**
-  private static final int FLV_HEADER_SIZE = 9;
+   * Extractor states.
-  private static final int FLV_TAG_HEADER_SIZE = 11;
+   */
-
+  @Retention(RetentionPolicy.SOURCE)
-  // Parser states.
+  @IntDef({STATE_READING_FLV_HEADER, STATE_SKIPPING_TO_TAG_HEADER, STATE_READING_TAG_HEADER,
+      STATE_READING_TAG_DATA})
+  private @interface States {}
   private static final int STATE_READING_FLV_HEADER = 1;
   private static final int STATE_SKIPPING_TO_TAG_HEADER = 2;
   private static final int STATE_READING_TAG_HEADER = 3;
   private static final int STATE_READING_TAG_DATA = 4;
 
+  // Header sizes.
+  private static final int FLV_HEADER_SIZE = 9;
+  private static final int FLV_TAG_HEADER_SIZE = 11;
+
   // Tag types.
   private static final int TAG_TYPE_AUDIO = 8;
   private static final int TAG_TYPE_VIDEO = 9;
@@ -71,11 +80,11 @@ public final class FlvExtractor implements Extractor, SeekMap {
   private ExtractorOutput extractorOutput;
 
   // State variables.
-  private int parserState;
+  private @States int state;
   private int bytesToNextTagHeader;
-  public int tagType;
+  private int tagType;
-  public int tagDataSize;
+  private int tagDataSize;
-  public long tagTimestampUs;
+  private long tagTimestampUs;
 
   // Tags readers.
   private AudioTagPayloadReader audioReader;
@@ -87,7 +96,7 @@ public final class FlvExtractor implements Extractor, SeekMap {
     headerBuffer = new ParsableByteArray(FLV_HEADER_SIZE);
     tagHeaderBuffer = new ParsableByteArray(FLV_TAG_HEADER_SIZE);
     tagData = new ParsableByteArray();
-    parserState = STATE_READING_FLV_HEADER;
+    state = STATE_READING_FLV_HEADER;
   }
 
   @Override
@@ -128,7 +137,7 @@ public final class FlvExtractor implements Extractor, SeekMap {
 
   @Override
   public void seek(long position, long timeUs) {
-    parserState = STATE_READING_FLV_HEADER;
+    state = STATE_READING_FLV_HEADER;
     bytesToNextTagHeader = 0;
   }
 
@@ -141,7 +150,7 @@ public final class FlvExtractor implements Extractor, SeekMap {
   public int read(ExtractorInput input, PositionHolder seekPosition) throws IOException,
       InterruptedException {
     while (true) {
-      switch (parserState) {
+      switch (state) {
         case STATE_READING_FLV_HEADER:
           if (!readFlvHeader(input)) {
             return RESULT_END_OF_INPUT;
@@ -160,6 +169,9 @@ public final class FlvExtractor implements Extractor, SeekMap {
             return RESULT_CONTINUE;
           }
           break;
+        default:
+          // Never happens.
+          throw new IllegalStateException();
       }
     }
   }
@@ -199,7 +211,7 @@ public final class FlvExtractor implements Extractor, SeekMap {
 
     // We need to skip any additional content in the FLV header, plus the 4 byte previous tag size.
     bytesToNextTagHeader = headerBuffer.readInt() - FLV_HEADER_SIZE + 4;
-    parserState = STATE_SKIPPING_TO_TAG_HEADER;
+    state = STATE_SKIPPING_TO_TAG_HEADER;
     return true;
   }
 
@@ -213,7 +225,7 @@ public final class FlvExtractor implements Extractor, SeekMap {
   private void skipToTagHeader(ExtractorInput input) throws IOException, InterruptedException {
     input.skipFully(bytesToNextTagHeader);
     bytesToNextTagHeader = 0;
-    parserState = STATE_READING_TAG_HEADER;
+    state = STATE_READING_TAG_HEADER;
   }
 
   /**
@@ -236,7 +248,7 @@ public final class FlvExtractor implements Extractor, SeekMap {
     tagTimestampUs = tagHeaderBuffer.readUnsignedInt24();
     tagTimestampUs = ((tagHeaderBuffer.readUnsignedByte() << 24) | tagTimestampUs) * 1000L;
     tagHeaderBuffer.skipBytes(3); // streamId
-    parserState = STATE_READING_TAG_DATA;
+    state = STATE_READING_TAG_DATA;
     return true;
   }
 
@@ -261,7 +273,7 @@ public final class FlvExtractor implements Extractor, SeekMap {
       wasConsumed = false;
     }
     bytesToNextTagHeader = 4; // There's a 4 byte previous tag size before the next header.
-    parserState = STATE_SKIPPING_TO_TAG_HEADER;
+    state = STATE_SKIPPING_TO_TAG_HEADER;
     return wasConsumed;
   }
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/mkv/MatroskaExtractor.java

@@ -53,7 +53,7 @@ import java.util.Locale;
 import java.util.UUID;
 
 /**
- * Extracts data from a Matroska or WebM file.
+ * Extracts data from the Matroska and WebM container formats.
  */
 public final class MatroskaExtractor implements Extractor {
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/mp3/Mp3Extractor.java

@@ -38,7 +38,7 @@ import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 
 /**
- * Extracts data from an MP3 file.
+ * Extracts data from the MP3 container format.
  */
 public final class Mp3Extractor implements Extractor {
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/mp3/XingSeeker.java

@@ -113,12 +113,13 @@ import com.google.android.exoplayer2.util.Util;
       fx = 256f;
     } else {
       int a = (int) percent;
-      float fa, fb;
+      float fa;
       if (a == 0) {
         fa = 0f;
       } else {
         fa = tableOfContents[a - 1];
       }
+      float fb;
       if (a < 99) {
         fb = tableOfContents[a];
       } else {

library/core/src/main/java/com/google/android/exoplayer2/extractor/mp4/FragmentedMp4Extractor.java

@@ -53,7 +53,7 @@ import java.util.Stack;
 import java.util.UUID;
 
 /**
- * Facilitates the extraction of data from the fragmented mp4 container format.
+ * Extracts data from the FMP4 container format.
  */
 public final class FragmentedMp4Extractor implements Extractor {
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/mp4/Mp4Extractor.java

@@ -41,7 +41,7 @@ import java.util.List;
 import java.util.Stack;
 
 /**
- * Extracts data from an unfragmented MP4 file.
+ * Extracts data from the MP4 container format.
  */
 public final class Mp4Extractor implements Extractor, SeekMap {
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/ogg/DefaultOggSeeker.java

@@ -186,7 +186,7 @@ import java.io.IOException;
         return start;
       }
 
-      long offset = pageSize * (granuleDistance <= 0 ? 2 : 1);
+      long offset = pageSize * (granuleDistance <= 0 ? 2L : 1L);
       long nextPosition = input.getPosition() - offset
           + (granuleDistance * (end - start) / (endGranule - startGranule));
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/ogg/FlacReader.java

@@ -118,9 +118,10 @@ import java.util.List;
       case 14:
       case 15:
         return 256 << (blockSizeCode - 8);
-    }
+      default:
         return -1;
     }
+  }
 
   private class FlacOggSeeker implements OggSeeker, SeekMap {
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/ogg/OggExtractor.java

@@ -27,7 +27,7 @@ import com.google.android.exoplayer2.util.ParsableByteArray;
 import java.io.IOException;
 
 /**
- * Ogg {@link Extractor}.
+ * Extracts data from the Ogg container format.
  */
 public class OggExtractor implements Extractor {
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/rawcc/RawCcExtractor.java

@@ -29,7 +29,7 @@ import com.google.android.exoplayer2.util.Util;
 import java.io.IOException;
 
 /**
- * Extracts CEA data from a RawCC file.
+ * Extracts data from the RawCC container format.
  */
 public final class RawCcExtractor implements Extractor {
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/ts/Ac3Extractor.java

@@ -29,7 +29,7 @@ import com.google.android.exoplayer2.util.Util;
 import java.io.IOException;
 
 /**
- * Extracts samples from (E-)AC-3 bitstreams.
+ * Extracts data from (E-)AC-3 bitstreams.
  */
 public final class Ac3Extractor implements Extractor {
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/ts/AdtsExtractor.java

@@ -29,7 +29,7 @@ import com.google.android.exoplayer2.util.Util;
 import java.io.IOException;
 
 /**
- * Extracts samples from AAC bit streams with ADTS framing.
+ * Extracts data from AAC bit streams with ADTS framing.
  */
 public final class AdtsExtractor implements Extractor {
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/ts/PsExtractor.java

@@ -31,7 +31,7 @@ import com.google.android.exoplayer2.util.TimestampAdjuster;
 import java.io.IOException;
 
 /**
- * Facilitates the extraction of data from the MPEG-2 PS container format.
+ * Extracts data from the MPEG-2 PS container format.
  */
 public final class PsExtractor implements Extractor {
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/ts/TsExtractor.java

@@ -45,7 +45,7 @@ import java.util.Collections;
 import java.util.List;
 
 /**
- * Facilitates the extraction of data from the MPEG-2 TS container format.
+ * Extracts data from the MPEG-2 TS container format.
  */
 public final class TsExtractor implements Extractor {
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/wav/WavExtractor.java

@@ -28,7 +28,9 @@ import com.google.android.exoplayer2.extractor.TrackOutput;
 import com.google.android.exoplayer2.util.MimeTypes;
 import java.io.IOException;
 
-/** {@link Extractor} to extract samples from a WAV byte stream. */
+/**
+ * Extracts data from WAV byte streams.
+ */
 public final class WavExtractor implements Extractor, SeekMap {
 
   /**