HBASE-10023 Fix/Suppress all the 10 findbug warnings under hbase-common (Liang Xie)

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1545257 13f79535-47bb-0310-9956-ffa450edef68

hbase-common/src/main/java/org/apache/hadoop/hbase/CellComparator.java

@@ -82,7 +82,7 @@ public class CellComparator implements Comparator<Cell>, Serializable{
     if (c != 0) return c;
 
     //timestamp: later sorts first
-    c = -Longs.compare(a.getTimestamp(), b.getTimestamp());
+    c = Longs.compare(b.getTimestamp(), a.getTimestamp());
     if (c != 0) return c;
 
     //type
@@ -90,7 +90,7 @@ public class CellComparator implements Comparator<Cell>, Serializable{
     if (c != 0) return c;
 
     //mvccVersion: later sorts first
-    return -Longs.compare(a.getMvccVersion(), b.getMvccVersion());
+    return Longs.compare(b.getMvccVersion(), a.getMvccVersion());
   }
 
 
@@ -197,7 +197,7 @@ public class CellComparator implements Comparator<Cell>, Serializable{
     if (c != 0) return c;
 
     //timestamp: later sorts first
-    c = -Longs.compare(a.getTimestamp(), b.getTimestamp());
+    c = Longs.compare(b.getTimestamp(), a.getTimestamp());
     if (c != 0) return c;
 
     //type

hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValue.java

@@ -2055,7 +2055,7 @@ public class KeyValue implements Cell, HeapSize, Cloneable {
 
       // compare Mvcc Version
       // Negate this comparison so later edits show up first
-      return -Longs.compare(left.getMvccVersion(), right.getMvccVersion());
+      return Longs.compare(right.getMvccVersion(), left.getMvccVersion());
     }
 
     public int compareTimestamps(final KeyValue left, final KeyValue right) {

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/BufferedDataBlockEncoder.java

@@ -156,11 +156,7 @@ abstract class BufferedDataBlockEncoder implements DataBlockEncoder {
     public BufferedEncodedSeeker(KVComparator comparator,
         HFileBlockDecodingContext decodingCtx) {
       this.comparator = comparator;
-      if (comparator instanceof SamePrefixComparator) {
-        this.samePrefixComparator = (SamePrefixComparator<byte[]>) comparator;
-      } else {
-        this.samePrefixComparator = null;
-      }
+      this.samePrefixComparator = comparator;
       this.decodingCtx = decodingCtx;
       if (decodingCtx.getHFileContext().isCompressTags()) {
         try {
@@ -468,9 +464,7 @@ abstract class BufferedDataBlockEncoder implements DataBlockEncoder {
     HFileBlockDefaultEncodingContext encodingCtx =
         (HFileBlockDefaultEncodingContext) blkEncodingCtx;
     encodingCtx.prepareEncoding();
-    DataOutputStream dataOut =
-        ((HFileBlockDefaultEncodingContext) encodingCtx)
-        .getOutputStreamForEncoder();
+    DataOutputStream dataOut = encodingCtx.getOutputStreamForEncoder();
     if (encodingCtx.getHFileContext().isCompressTags()) {
       try {
         TagCompressionContext tagCompressionContext = new TagCompressionContext(LRUDictionary.class);

hbase-common/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileContext.java

@@ -155,16 +155,10 @@ public class HFileContext implements HeapSize, Cloneable {
 
   @Override
   public HFileContext clone() {
-    HFileContext clonnedCtx = new HFileContext();
-    clonnedCtx.usesHBaseChecksum = this.usesHBaseChecksum;
-    clonnedCtx.includesMvcc = this.includesMvcc;
-    clonnedCtx.includesTags = this.includesTags;
-    clonnedCtx.compressAlgo = this.compressAlgo;
-    clonnedCtx.compressTags = this.compressTags;
-    clonnedCtx.checksumType = this.checksumType;
-    clonnedCtx.bytesPerChecksum = this.bytesPerChecksum;
-    clonnedCtx.blocksize = this.blocksize;
-    clonnedCtx.encoding = this.encoding;
-    return clonnedCtx;
+    try {
+      return (HFileContext)(super.clone());
+    } catch (CloneNotSupportedException e) {
+      throw new AssertionError(); // Won't happen
+    }
   }
 }

hbase-common/src/main/java/org/apache/hadoop/hbase/util/Bytes.java

@@ -190,14 +190,12 @@ public class Bytes {
   /**
    * Pass this to TreeMaps where byte [] are keys.
    */
-  public static Comparator<byte []> BYTES_COMPARATOR =
-    new ByteArrayComparator();
+  public final static Comparator<byte []> BYTES_COMPARATOR = new ByteArrayComparator();
 
   /**
    * Use comparing byte arrays, byte-by-byte
    */
-  public static RawComparator<byte []> BYTES_RAWCOMPARATOR =
-    new ByteArrayComparator();
+  public final static RawComparator<byte []> BYTES_RAWCOMPARATOR = new ByteArrayComparator();
 
   /**
    * Read byte-array written with a WritableableUtils.vint prefix.

hbase-common/src/main/java/org/apache/hadoop/hbase/util/ChecksumType.java

@@ -49,7 +49,7 @@ public enum ChecksumType {
   },
 
   CRC32((byte)1) {
-    private volatile Constructor<?> ctor;
+    private transient Constructor<?> ctor;
 
     @Override
     public String getName() {

hbase-common/src/main/java/org/apache/hadoop/hbase/util/ConcatenatedLists.java

@@ -129,6 +129,9 @@ public class ConcatenatedLists<T> implements Collection<T> {
     return new Iterator();
   }
 
+  @edu.umd.cs.findbugs.annotations.SuppressWarnings(
+    value="URF_UNREAD_PUBLIC_OR_PROTECTED_FIELD",
+    justification="nextWasCalled is using by StripeStoreFileManager")
   public class Iterator implements java.util.Iterator<T> {
     protected int currentComponent = 0;
     protected int indexWithinComponent = -1;

hbase-common/src/main/java/org/apache/hadoop/hbase/util/JVM.java

@@ -184,6 +184,9 @@ public class JVM {
    * Workaround to get the current number of process running. Approach is the one described here:
    * http://stackoverflow.com/questions/54686/how-to-get-a-list-of-current-open-windows-process-with-java
    */
+  @edu.umd.cs.findbugs.annotations.SuppressWarnings(
+    value="RV_DONT_JUST_NULL_CHECK_READLINE",
+    justification="used by testing")
   public int getNumberOfRunningProcess(){
     if (!isUnix()){
       return 0;

hbase-common/src/main/java/org/apache/hadoop/hbase/util/KeyLocker.java

@@ -117,7 +117,7 @@ public class KeyLocker<K extends Comparable<? super K>> {
   static class KeyLock<K extends Comparable<? super K>> extends ReentrantLock {
     private static final long serialVersionUID = -12432857283423584L;
 
-    private final KeyLocker<K> locker;
+    private final transient KeyLocker<K> locker;
     private final K lockId;
 
     private KeyLock(KeyLocker<K> locker, K lockId) {