HBASE-22571 Javadoc Warnings related to @return tag

Signed-off-by: Jan Hentschel <jan.hentschel@ultratendency.com>

hbase-client/src/main/java/org/apache/hadoop/hbase/client/SimpleRequestController.java

@@ -433,7 +433,7 @@ class SimpleRequestController implements RequestController {
      *
      * @param loc
      * @param heapSizeOfRow
-     * @return
+     * @return either Include {@link ReturnCode} or Skip {@link ReturnCode}
      */
     @Override
     public ReturnCode canTakeOperation(HRegionLocation loc, long heapSizeOfRow) {

hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapred/TestTableInputFormat.java

@@ -143,11 +143,11 @@ public class TestTableInputFormat {
   /**
    * Verify that the result and key have expected values.
    *
-   * @param r
+   * @param r single row result
-   * @param key
+   * @param key the row key
-   * @param expectedKey
+   * @param expectedKey the expected key
-   * @param expectedValue
+   * @param expectedValue the expected value
-   * @return
+   * @return true if the result contains the expected key and value, false otherwise.
    */
   static boolean checkResult(Result r, ImmutableBytesWritable key,
       byte[] expectedKey, byte[] expectedValue) {

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

@@ -141,11 +141,11 @@ public class TestTableInputFormat {
   /**
    * Verify that the result and key have expected values.
    *
-   * @param r
+   * @param r single row result
-   * @param key
+   * @param key the row key
-   * @param expectedKey
+   * @param expectedKey the expected key
-   * @param expectedValue
+   * @param expectedValue the expected value
-   * @return
+   * @return true if the result contains the expected key and value, false otherwise.
    */
   static boolean checkResult(Result r, ImmutableBytesWritable key,
       byte[] expectedKey, byte[] expectedValue) {

hbase-server/src/main/java/org/apache/hadoop/hbase/client/VersionInfoUtil.java

@@ -149,7 +149,7 @@ public final class VersionInfoUtil {
   /**
    * Returns the version components
    * Examples: "1.4.3" returns [1, 4, 3], "4.5.6-SNAPSHOT" returns [4, 5, 6, "SNAPSHOT"]
-   * @returns the components of the version string
+   * @return the components of the version string
    */
   private static String[] getVersionComponents(final HBaseProtos.VersionInfo versionInfo) {
     return versionInfo.getVersion().split("[\\.-]");

hbase-server/src/main/java/org/apache/hadoop/hbase/client/locking/EntityLock.java

@@ -218,8 +218,7 @@ public class EntityLock {
     }
 
     /**
-     * Shutdown the thread cleanly, quietly. We done.
+     * @return Shuts down the thread clean and quietly.
-     * @return
      */
     Thread shutdown() {
       shutdown = true;

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

@@ -4089,8 +4089,8 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
 
   /**
    * Called to do a piece of the batch that came in to {@link #batchMutate(Mutation[], long, long)}
-   * In here we also handle replay of edits on region recover.
+   * In here we also handle replay of edits on region recover. Also gets change in size brought
-   * @return Change in size brought about by applying <code>batchOp</code>
+   * about by applying {@code batchOp}.
    */
   private void doMiniBatchMutate(BatchOperation<?> batchOp) throws IOException {
     boolean success = false;

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

@@ -300,7 +300,6 @@ public class MemStoreLABImpl implements MemStoreLAB {
    * <code>c</code>. Postcondition is that curChunk.get()
    * != c
    * @param c the chunk to retire
-   * @return true if we won the race to retire the chunk
    */
   private void tryRetireChunk(Chunk c) {
     currChunk.compareAndSet(c, null);

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

@@ -539,7 +539,7 @@ public class RSRpcServices implements HBaseRPCErrorHandler,
    * Starts the nonce operation for a mutation, if needed.
    * @param mutation Mutation.
    * @param nonceGroup Nonce group from the request.
-   * @returns whether to proceed this mutation.
+   * @return whether to proceed this mutation.
    */
   private boolean startNonceOperation(final MutationProto mutation, long nonceGroup)
       throws IOException {

hbase-server/src/main/java/org/apache/hadoop/hbase/snapshot/SnapshotInfo.java

@@ -614,7 +614,6 @@ public final class SnapshotInfo extends AbstractHBaseTool {
    * @param uniqueHFilesArchiveSize {@link AtomicLong} the accumulated store file size in archive
    * @param uniqueHFilesSize {@link AtomicLong} the accumulated store file size shared
    * @param uniqueHFilesMobSize {@link AtomicLong} the accumulated mob store file size shared
-   * @return the snapshot stats
    */
   private static void getSnapshotFilesMap(final Configuration conf,
       final SnapshotDescription snapshot, final ExecutorService exec,

hbase-server/src/test/java/org/apache/hadoop/hbase/HBaseCluster.java

@@ -118,14 +118,12 @@ public abstract class HBaseCluster implements Closeable, Configurable {
 
   /**
    * Stops the given region server, by attempting a gradual stop.
-   * @return whether the operation finished with success
    * @throws IOException if something goes wrong
    */
   public abstract void stopRegionServer(ServerName serverName) throws IOException;
 
   /**
    * Wait for the specified region server to join the cluster
-   * @return whether the operation finished with success
    * @throws IOException if something goes wrong or timeout occurs
    */
   public void waitForRegionServerToStart(String hostname, int port, long timeout)
@@ -145,7 +143,6 @@ public abstract class HBaseCluster implements Closeable, Configurable {
 
   /**
    * Wait for the specified region server to stop the thread / process.
-   * @return whether the operation finished with success
    * @throws IOException if something goes wrong or timeout occurs
    */
   public abstract void waitForRegionServerToStop(ServerName serverName, long timeout)
@@ -175,7 +172,6 @@ public abstract class HBaseCluster implements Closeable, Configurable {
 
   /**
    * Wait for the specified zookeeper node to join the cluster
-   * @return whether the operation finished with success
    * @throws IOException if something goes wrong or timeout occurs
    */
   public abstract void waitForZkNodeToStart(ServerName serverName, long timeout)
@@ -183,7 +179,6 @@ public abstract class HBaseCluster implements Closeable, Configurable {
 
   /**
    * Wait for the specified zookeeper node to stop the thread / process.
-   * @return whether the operation finished with success
    * @throws IOException if something goes wrong or timeout occurs
    */
   public abstract void waitForZkNodeToStop(ServerName serverName, long timeout)
@@ -212,7 +207,6 @@ public abstract class HBaseCluster implements Closeable, Configurable {
 
   /**
    * Wait for the specified datanode to join the cluster
-   * @return whether the operation finished with success
    * @throws IOException if something goes wrong or timeout occurs
    */
   public abstract void waitForDataNodeToStart(ServerName serverName, long timeout)
@@ -220,7 +214,6 @@ public abstract class HBaseCluster implements Closeable, Configurable {
 
   /**
    * Wait for the specified datanode to stop the thread / process.
-   * @return whether the operation finished with success
    * @throws IOException if something goes wrong or timeout occurs
    */
   public abstract void waitForDataNodeToStop(ServerName serverName, long timeout)
@@ -248,7 +241,6 @@ public abstract class HBaseCluster implements Closeable, Configurable {
 
   /**
    * Wait for the specified namenode to join the cluster
-   * @return whether the operation finished with success
    * @throws IOException if something goes wrong or timeout occurs
    */
   public abstract void waitForNameNodeToStart(ServerName serverName, long timeout)
@@ -256,7 +248,6 @@ public abstract class HBaseCluster implements Closeable, Configurable {
 
   /**
    * Wait for the specified namenode to stop
-   * @return whether the operation finished with success
    * @throws IOException if something goes wrong or timeout occurs
    */
   public abstract void waitForNameNodeToStop(ServerName serverName, long timeout)
@@ -266,7 +257,6 @@ public abstract class HBaseCluster implements Closeable, Configurable {
    * Starts a new master on the given hostname or if this is a mini/local cluster,
    * starts a master locally.
    * @param hostname the hostname to start the master on
-   * @return whether the operation finished with success
    * @throws IOException if something goes wrong
    */
   public abstract void startMaster(String hostname, int port) throws IOException;

hbase-server/src/test/java/org/apache/hadoop/hbase/HBaseTestingUtility.java

@@ -3700,7 +3700,7 @@ public class HBaseTestingUtility extends HBaseZKTestingUtility {
    * @param startKey
    * @param endKey
    * @param numRegions the number of regions to be created. it has to be greater than 3.
-   * @return
+   * @return resulting split keys
    */
   public byte[][] getRegionSplitStartKeys(byte[] startKey, byte[] endKey, int numRegions){
     assertTrue(numRegions>3);

hbase-server/src/test/java/org/apache/hadoop/hbase/TestServerSideScanMetricsFromClientSide.java

@@ -109,6 +109,12 @@ public class TestServerSideScanMetricsFromClientSide {
 
   /**
    * Make puts to put the input value into each combination of row, family, and qualifier
+   * @param rows the rows to use
+   * @param families the column families to use
+   * @param qualifiers the column qualifiers to use
+   * @param value the value to put
+   * @return the putted input values added in puts
+   * @throws IOException If an IO problem is encountered
    */
   private static ArrayList<Put> createPuts(byte[][] rows, byte[][] families, byte[][] qualifiers,
       byte[] value) throws IOException {
@@ -133,6 +139,7 @@ public class TestServerSideScanMetricsFromClientSide {
    * @return The approximate heap size of a cell in the test table. All cells should have
    *         approximately the same heap size, so the value is cached to avoid repeating the
    *         calculation
+   * @throws Exception on unexpected failure
    */
   private long getCellHeapSize() throws Exception {
     if (CELL_HEAP_SIZE == -1) {
@@ -309,7 +316,11 @@ public class TestServerSideScanMetricsFromClientSide {
   }
 
   /**
-   * Run the scan to completion and check the metric against the specified value
+   * Run the scan to completetion and check the metric against the specified value
+   * @param scan The scan instance to use to record metrics
+   * @param metricKey The metric key name
+   * @param expectedValue The expected value of metric
+   * @throws Exception on unexpected failure
    */
   private void testMetric(Scan scan, String metricKey, long expectedValue) throws Exception {
     assertTrue("Scan should be configured to record metrics", scan.isScanMetricsEnabled());

hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestOpenTableInCoprocessor.java

@@ -94,9 +94,8 @@ public class TestOpenTableInCoprocessor {
   public static class CustomThreadPoolCoprocessor implements RegionCoprocessor, RegionObserver {
 
     /**
-     * Get a pool that has only ever one thread. A second action added to the pool (running
+     * @return a pool that has one thread only at every time. A second action added to the pool (
-     * concurrently), will cause an exception.
+     *         running concurrently), will cause an exception.
-     * @return
      */
     private ExecutorService getPool() {
       int maxThreads = 1;

hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/RandomKeyValueUtil.java

@@ -79,10 +79,9 @@ public class RandomKeyValueUtil {
    * increases. The result consists of a prefix, which is a deterministic
    * increasing function of i, and a random suffix.
    *
-   * @param rand
+   * @param rand random number generator to use
-   *          random number generator to use
    * @param i
-   * @return
+   * @return the random key
    */
   public static byte[] randomOrderedKey(Random rand, int i) {
     StringBuilder k = new StringBuilder();

hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestRegionPlacement.java

@@ -301,7 +301,7 @@ public class TestRegionPlacement {
    * @param plan The assignment plan
    * @param p1 The first switch position
    * @param p2 The second switch position
-   * @return
+   * @return the shuffled assignment plan
    */
   private FavoredNodesPlan shuffleAssignmentPlan(FavoredNodesPlan plan,
       FavoredNodesPlan.Position p1, FavoredNodesPlan.Position p2) throws IOException {

hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/BalancerTestBase.java

@@ -328,7 +328,7 @@ public class BalancerTestBase {
    *
    * @param list
    * @param plans
-   * @return
+   * @return a list of all added {@link ServerAndLoad} values.
    */
   protected List<ServerAndLoad> reconcile(List<ServerAndLoad> list,
                                           List<RegionPlan> plans,

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHStore.java

@@ -794,7 +794,7 @@ public class TestHStore {
    * @param numRows
    * @param qualifier
    * @param family
-   * @return
+   * @return the rows key-value list
    */
   List<Cell> getKeyValueSet(long[] timestamps, int numRows,
       byte[] qualifier, byte[] family) {

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHStoreFile.java

@@ -844,7 +844,7 @@ public class TestHStoreFile extends HBaseTestCase {
    * @param numRows
    * @param qualifier
    * @param family
-   * @return
+   * @return the rows key-value list
    */
   List<KeyValue> getKeyValueSet(long[] timestamps, int numRows,
       byte[] qualifier, byte[] family) {

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestMobStoreScanner.java

@@ -130,7 +130,6 @@ public class TestMobStoreScanner {
    *
    * @param reversed if true, scan will be backward order
    * @param mobScanRaw if true, scan will get the mob reference
-   * @return this
    */
   public void setScan(Scan scan, boolean reversed, boolean mobScanRaw) {
     scan.setReversed(reversed);

hbase-server/src/test/java/org/apache/hadoop/hbase/util/MultiThreadedAction.java

@@ -320,7 +320,8 @@ public abstract class MultiThreadedAction {
    * @param verifyCfAndColumnIntegrity verify that cf/column set in the result is complete. Note
    *                                   that to use this multiPut should be used, or verification
    *                                   has to happen after writes, otherwise there can be races.
-   * @return
+   * @return true if the values of row result makes sense for row/cf/column combination and true if
+   *         the cf/column set in the result is complete, false otherwise.
    */
   public boolean verifyResultAgainstDataGenerator(Result result, boolean verifyValues,
       boolean verifyCfAndColumnIntegrity) {

hbase-server/src/test/java/org/apache/hadoop/hbase/util/test/LoadTestDataGenerator.java

@@ -165,8 +165,7 @@ public abstract class LoadTestDataGenerator {
   }
 
   /**
-   * Return the arguments passed to the generator as list of object
+   * @return the arguments passed to the generator as a list of objects.
-   * @return
    */
   public String[] getArgs() {
     return this.args;

hbase-zookeeper/src/main/java/org/apache/hadoop/hbase/zookeeper/MiniZooKeeperCluster.java

@@ -126,7 +126,7 @@ public class MiniZooKeeperCluster {
    * Selects a ZK client port.
    *
    * @param seedPort the seed port to start with; -1 means first time.
-   * @Returns a valid and unused client port
+   * @return a valid and unused client port
    */
   private int selectClientPort(int seedPort) {
     int i;