HBASE-23622 Reduced the number of Checkstyle violations in hbase-common

hbase-checkstyle/src/main/resources/hbase/checkstyle-suppressions.xml

@@ -34,4 +34,6 @@
   <suppress checks="." files=".*/generated/.*\.java"/>
   <suppress checks="." files=".*/generated-jamon/.*\.java"/>
   <suppress checks="MagicNumberCheck" files=".*Test\.java"/>
+  <!-- Will not have a private constructor, because it is InterfaceAudience.Public -->
+  <suppress checks="HideUtilityClassConstructor" files="org.apache.hadoop.hbase.util.ByteRangeUtils"/>
 </suppressions>

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

@@ -55,7 +55,7 @@ public int compare(Cell a, Cell b) {
    * @param a
    * @param b
    * @param ignoreSequenceid True if we are to compare the key portion only and ignore
-   * the sequenceid. Set to false to compare key and consider sequenceid.
+   *    the sequenceid. Set to false to compare key and consider sequenceid.
    * @return 0 if equal, -1 if a < b, and +1 if a > b.
    */
   public static int compare(final Cell a, final Cell b, boolean ignoreSequenceid) {

hbase-common/src/main/java/org/apache/hadoop/hbase/net/Address.java

@@ -26,7 +26,7 @@
  * An immutable type to hold a hostname and port combo, like an Endpoint
  * or java.net.InetSocketAddress (but without danger of our calling
  * resolve -- we do NOT want a resolve happening every time we want
- * to hold a hostname and port combo). This class is also <<Comparable>>.
+ * to hold a hostname and port combo). This class is also {@link Comparable}
  * <p>In implementation this class is a facade over Guava's {@link HostAndPort}.
  * We cannot have Guava classes in our API hence this Type.
  */
@@ -83,7 +83,10 @@ public int hashCode() {
   @Override
   public int compareTo(Address that) {
     int compare = this.getHostname().compareTo(that.getHostname());
-    if (compare != 0) return compare;
+    if (compare != 0) {
+      return compare;
+    }
+
     return this.getPort() - that.getPort();
   }
 }

hbase-common/src/main/java/org/apache/hadoop/hbase/trace/SpanReceiverHost.java

@@ -43,7 +43,7 @@ public class SpanReceiverHost {
   private boolean closed = false;
 
   @edu.umd.cs.findbugs.annotations.SuppressWarnings(value="SE_BAD_FIELD")
-  private static enum SingletonHolder {
+  private enum SingletonHolder {
     INSTANCE;
     final Object lock = new Object();
     SpanReceiverHost host = null; // FindBugs: SE_BAD_FIELD
@@ -64,14 +64,13 @@ public static SpanReceiverHost getInstance(Configuration conf) {
   }
 
   SpanReceiverHost(Configuration conf) {
-    receivers = new HashSet<SpanReceiver>();
+    receivers = new HashSet<>();
     this.conf = conf;
   }
 
   /**
    * Reads the names of classes specified in the {@code hbase.trace.spanreceiver.classes} property
    * and instantiates and registers them with the Tracer.
-   *
    */
   public void loadSpanReceivers() {
     String[] receiverNames = conf.getStrings(SPAN_RECEIVERS_CONF_KEY);
@@ -98,7 +97,10 @@ public void loadSpanReceivers() {
    * Calls close() on all SpanReceivers created by this SpanReceiverHost.
    */
   public synchronized void closeReceivers() {
-    if (closed) return;
+    if (closed) {
+      return;
+    }
+
     closed = true;
     for (SpanReceiver rcvr : receivers) {
       try {

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

@@ -15,9 +15,10 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.apache.hadoop.hbase.util;
 
+import com.google.common.collect.Lists;
+
 import java.io.IOException;
 import java.io.OutputStream;
 import java.util.ArrayList;
@@ -26,19 +27,18 @@
 import org.apache.hadoop.hbase.classification.InterfaceAudience;
 import org.apache.hadoop.hbase.classification.InterfaceStability;
 
-import com.google.common.collect.Lists;
-
 /**
  * Utility methods for working with {@link ByteRange}.
  */
 @InterfaceAudience.Public
 @InterfaceStability.Evolving
 public class ByteRangeUtils {
-
   public static int numEqualPrefixBytes(ByteRange left, ByteRange right, int rightInnerOffset) {
     int maxCompares = Math.min(left.getLength(), right.getLength() - rightInnerOffset);
-    final byte[] lbytes = left.getBytes(), rbytes = right.getBytes();
-    final int loffset = left.getOffset(), roffset = right.getOffset();
+    final byte[] lbytes = left.getBytes();
+    final byte[] rbytes = right.getBytes();
+    final int loffset = left.getOffset();
+    final int roffset = right.getOffset();
     for (int i = 0; i < maxCompares; ++i) {
       if (lbytes[loffset + i] != rbytes[roffset + rightInnerOffset + i]) {
         return i;
@@ -49,7 +49,7 @@ public static int numEqualPrefixBytes(ByteRange left, ByteRange right, int right
 
   public static ArrayList<byte[]> copyToNewArrays(Collection<ByteRange> ranges) {
     if (ranges == null) {
-      return new ArrayList<byte[]>(0);
+      return new ArrayList<>(0);
     }
     ArrayList<byte[]> arrays = Lists.newArrayListWithCapacity(ranges.size());
     for (ByteRange range : ranges) {
@@ -60,7 +60,7 @@ public static ArrayList<byte[]> copyToNewArrays(Collection<ByteRange> ranges) {
 
   public static ArrayList<ByteRange> fromArrays(Collection<byte[]> arrays) {
     if (arrays == null) {
-      return new ArrayList<ByteRange>(0);
+      return new ArrayList<>(0);
     }
     ArrayList<ByteRange> ranges = Lists.newArrayListWithCapacity(arrays.size());
     for (byte[] array : arrays) {
@@ -78,5 +78,4 @@ public static void write(OutputStream os, ByteRange byteRange, int byteRangeInne
     os.write(byteRange.getBytes(), byteRange.getOffset() + byteRangeInnerOffset,
       byteRange.getLength() - byteRangeInnerOffset);
   }
-
 }