diff --git a/hbase-examples/src/main/java/org/apache/hadoop/hbase/coprocessor/example/row/stats/RowStatisticsCompactionObserver.java b/hbase-examples/src/main/java/org/apache/hadoop/hbase/coprocessor/example/row/stats/RowStatisticsCompactionObserver.java
index 78e92aa18ae2..78ead4f17def 100644
--- a/hbase-examples/src/main/java/org/apache/hadoop/hbase/coprocessor/example/row/stats/RowStatisticsCompactionObserver.java
+++ b/hbase-examples/src/main/java/org/apache/hadoop/hbase/coprocessor/example/row/stats/RowStatisticsCompactionObserver.java
@@ -168,9 +168,8 @@ public void postStartMaster(ObserverContext<MasterCoprocessorEnvironment> ctx)
         LOG.info("Table {} already exists. Skipping table creation process.",
           NAMESPACED_TABLE_NAME);
       } else {
-        boolean shouldCreateNamespace =
-          Arrays.stream(admin.listNamespaces()).filter(namespace -> namespace.equals(NAMESPACE))
-            .collect(Collectors.toUnmodifiableSet()).isEmpty();
+        boolean shouldCreateNamespace = Arrays.stream(admin.listNamespaces())
+          .filter(namespace -> namespace.equals(NAMESPACE)).collect(Collectors.toSet()).isEmpty();
         if (shouldCreateNamespace) {
           NamespaceDescriptor nd = NamespaceDescriptor.create(NAMESPACE).build();
           try {
@@ -180,7 +179,7 @@ public void postStartMaster(ObserverContext<MasterCoprocessorEnvironment> ctx)
           }
         }
         ColumnFamilyDescriptor cfd = ColumnFamilyDescriptorBuilder.newBuilder(CF).setMaxVersions(25)
-          .setTimeToLive((int) Duration.ofDays(7).toSeconds()).build();
+          .setTimeToLive((int) Duration.ofDays(7).getSeconds()).build();
         TableDescriptor td =
           TableDescriptorBuilder.newBuilder(NAMESPACED_TABLE_NAME).setColumnFamily(cfd).build();
         LOG.info("Creating table {}", NAMESPACED_TABLE_NAME);
@@ -197,7 +196,7 @@ public void postStartMaster(ObserverContext<MasterCoprocessorEnvironment> ctx)
   }
 
   @Override
-  public InternalScanner preCompact(ObserverContext<? extends RegionCoprocessorEnvironment> context,
+  public InternalScanner preCompact(ObserverContext<RegionCoprocessorEnvironment> context,
     Store store, InternalScanner scanner, ScanType scanType, CompactionLifeCycleTracker tracker,
     CompactionRequest request) {
     if (store.getTableName().isSystemTable()) {
@@ -242,15 +241,14 @@ public RowStatisticsScanner(InternalScanner scanner, RowStatisticsImpl rowStatis
     }
 
     @Override
-    public boolean next(List<? super ExtendedCell> result, ScannerContext scannerContext)
-      throws IOException {
+    public boolean next(List<Cell> result, ScannerContext scannerContext) throws IOException {
       boolean ret = scanner.next(result, scannerContext);
       consumeCells(result);
       return ret;
     }
 
     @Override
-    public boolean next(List<? super ExtendedCell> result) throws IOException {
+    public boolean next(List<Cell> result) throws IOException {
       boolean ret = scanner.next(result);
       consumeCells(result);
       return ret;
diff --git a/hbase-examples/src/test/java/org/apache/hadoop/hbase/coprocessor/example/row/stats/TestRowStatisticsCompactionObserver.java b/hbase-examples/src/test/java/org/apache/hadoop/hbase/coprocessor/example/row/stats/TestRowStatisticsCompactionObserver.java
index d0ee8d3bc578..f763ba40f9fa 100644
--- a/hbase-examples/src/test/java/org/apache/hadoop/hbase/coprocessor/example/row/stats/TestRowStatisticsCompactionObserver.java
+++ b/hbase-examples/src/test/java/org/apache/hadoop/hbase/coprocessor/example/row/stats/TestRowStatisticsCompactionObserver.java
@@ -28,7 +28,7 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.HConstants;
-import org.apache.hadoop.hbase.SingleProcessHBaseCluster;
+import org.apache.hadoop.hbase.MiniHBaseCluster;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.client.Connection;
 import org.apache.hadoop.hbase.client.ConnectionFactory;
@@ -47,7 +47,7 @@ public class TestRowStatisticsCompactionObserver {
   public static final TestableRowStatisticsRecorder RECORDER = new TestableRowStatisticsRecorder();
   private static final TableName TABLE_NAME = TableName.valueOf("test-table");
   private static final byte[] FAMILY = Bytes.toBytes("0");
-  private static SingleProcessHBaseCluster cluster;
+  private static MiniHBaseCluster cluster;
   private static Connection connection;
   private static Table table;
 
diff --git a/hbase-examples/src/test/java/org/apache/hadoop/hbase/coprocessor/example/row/stats/TestRowStatisticsTableRecorder.java b/hbase-examples/src/test/java/org/apache/hadoop/hbase/coprocessor/example/row/stats/TestRowStatisticsTableRecorder.java
index 39a7e36c2022..a45e01fc9d97 100644
--- a/hbase-examples/src/test/java/org/apache/hadoop/hbase/coprocessor/example/row/stats/TestRowStatisticsTableRecorder.java
+++ b/hbase-examples/src/test/java/org/apache/hadoop/hbase/coprocessor/example/row/stats/TestRowStatisticsTableRecorder.java
@@ -28,8 +28,8 @@
 import java.io.IOException;
 import java.util.Optional;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.MiniHBaseCluster;
 import org.apache.hadoop.hbase.NamespaceDescriptor;
-import org.apache.hadoop.hbase.SingleProcessHBaseCluster;
 import org.apache.hadoop.hbase.client.BufferedMutatorParams;
 import org.apache.hadoop.hbase.client.Connection;
 import org.apache.hadoop.hbase.client.ConnectionFactory;
@@ -50,7 +50,7 @@ public class TestRowStatisticsTableRecorder {
   private static final NamespaceDescriptor NAMESPACE_DESCRIPTOR =
     NamespaceDescriptor.create(RowStatisticsTableUtil.NAMESPACE).build();
   private static final byte[] FULL_REGION_NAME = Bytes.toBytes("fullRegionName");
-  private static SingleProcessHBaseCluster cluster;
+  private static MiniHBaseCluster cluster;
   private static Connection connection;
   private RowStatisticsImpl rowStatistics;
   private Counter counter;