HBASE-24945 Remove MetaTableAccessor.getRegionCount (#2303)

Signed-off-by: Viraj Jasani <vjasani@apache.org>

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

@@ -37,10 +37,8 @@ import java.util.SortedMap;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import java.util.stream.Collectors;
-import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Cell.Type;
 import org.apache.hadoop.hbase.client.Connection;
-import org.apache.hadoop.hbase.client.ConnectionFactory;
 import org.apache.hadoop.hbase.client.Consistency;
 import org.apache.hadoop.hbase.client.Delete;
 import org.apache.hadoop.hbase.client.Get;
@@ -48,7 +46,6 @@ import org.apache.hadoop.hbase.client.Mutation;
 import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.hbase.client.RegionInfo;
 import org.apache.hadoop.hbase.client.RegionInfoBuilder;
-import org.apache.hadoop.hbase.client.RegionLocator;
 import org.apache.hadoop.hbase.client.RegionReplicaUtil;
 import org.apache.hadoop.hbase.client.Result;
 import org.apache.hadoop.hbase.client.ResultScanner;
@@ -1325,33 +1322,6 @@ public class MetaTableAccessor {
     }
   }
 
-  /**
-   * Count regions in <code>hbase:meta</code> for passed table.
-   * @param c Configuration object
-   * @param tableName table name to count regions for
-   * @return Count or regions in table <code>tableName</code>
-   */
-  public static int getRegionCount(final Configuration c, final TableName tableName)
-      throws IOException {
-    try (Connection connection = ConnectionFactory.createConnection(c)) {
-      return getRegionCount(connection, tableName);
-    }
-  }
-
-  /**
-   * Count regions in <code>hbase:meta</code> for passed table.
-   * @param connection Connection object
-   * @param tableName table name to count regions for
-   * @return Count or regions in table <code>tableName</code>
-   */
-  public static int getRegionCount(final Connection connection, final TableName tableName)
-      throws IOException {
-    try (RegionLocator locator = connection.getRegionLocator(tableName)) {
-      List<HRegionLocation> locations = locator.getAllRegionLocations();
-      return locations == null ? 0 : locations.size();
-    }
-  }
-
   ////////////////////////
   // Editing operations //
   ////////////////////////

hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapred/TableMapReduceUtil.java

@@ -18,14 +18,15 @@
  */
 package org.apache.hadoop.hbase.mapred;
 
+import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.HBaseConfiguration;
-import org.apache.hadoop.hbase.MetaTableAccessor;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.client.Connection;
 import org.apache.hadoop.hbase.client.ConnectionFactory;
 import org.apache.hadoop.hbase.client.Put;
+import org.apache.hadoop.hbase.client.RegionLocator;
 import org.apache.hadoop.hbase.client.Scan;
 import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
 import org.apache.hadoop.hbase.mapreduce.MutationSerialization;
@@ -280,8 +281,7 @@ public class TableMapReduceUtil {
         MutationSerialization.class.getName(), ResultSerialization.class.getName());
     if (partitioner == HRegionPartitioner.class) {
       job.setPartitionerClass(HRegionPartitioner.class);
-      int regions =
+      int regions = getRegionCount(HBaseConfiguration.create(job), TableName.valueOf(table));
-        MetaTableAccessor.getRegionCount(HBaseConfiguration.create(job), TableName.valueOf(table));
       if (job.getNumReduceTasks() > regions) {
         job.setNumReduceTasks(regions);
       }
@@ -327,13 +327,12 @@ public class TableMapReduceUtil {
    * @throws IOException When retrieving the table details fails.
    */
   // Used by tests.
-  public static void limitNumReduceTasks(String table, JobConf job)
+  public static void limitNumReduceTasks(String table, JobConf job) throws IOException {
-  throws IOException {
+    int regions = getRegionCount(HBaseConfiguration.create(job), TableName.valueOf(table));
-    int regions =
+    if (job.getNumReduceTasks() > regions) {
-      MetaTableAccessor.getRegionCount(HBaseConfiguration.create(job), TableName.valueOf(table));
-    if (job.getNumReduceTasks() > regions)
       job.setNumReduceTasks(regions);
     }
+  }
 
   /**
    * Ensures that the given number of map tasks for the given job
@@ -344,13 +343,12 @@ public class TableMapReduceUtil {
    * @throws IOException When retrieving the table details fails.
    */
   // Used by tests.
-  public static void limitNumMapTasks(String table, JobConf job)
+  public static void limitNumMapTasks(String table, JobConf job) throws IOException {
-  throws IOException {
+    int regions = getRegionCount(HBaseConfiguration.create(job), TableName.valueOf(table));
-    int regions =
+    if (job.getNumMapTasks() > regions) {
-      MetaTableAccessor.getRegionCount(HBaseConfiguration.create(job), TableName.valueOf(table));
-    if (job.getNumMapTasks() > regions)
       job.setNumMapTasks(regions);
     }
+  }
 
   /**
    * Sets the number of reduce tasks for the given job configuration to the
@@ -360,10 +358,8 @@ public class TableMapReduceUtil {
    * @param job  The current job configuration to adjust.
    * @throws IOException When retrieving the table details fails.
    */
-  public static void setNumReduceTasks(String table, JobConf job)
+  public static void setNumReduceTasks(String table, JobConf job) throws IOException {
-  throws IOException {
+    job.setNumReduceTasks(getRegionCount(HBaseConfiguration.create(job), TableName.valueOf(table)));
-    job.setNumReduceTasks(MetaTableAccessor.getRegionCount(HBaseConfiguration.create(job),
-      TableName.valueOf(table)));
   }
 
   /**
@@ -374,10 +370,8 @@ public class TableMapReduceUtil {
    * @param job  The current job configuration to adjust.
    * @throws IOException When retrieving the table details fails.
    */
-  public static void setNumMapTasks(String table, JobConf job)
+  public static void setNumMapTasks(String table, JobConf job) throws IOException {
-  throws IOException {
+    job.setNumMapTasks(getRegionCount(HBaseConfiguration.create(job), TableName.valueOf(table)));
-    job.setNumMapTasks(MetaTableAccessor.getRegionCount(HBaseConfiguration.create(job),
-      TableName.valueOf(table)));
   }
 
   /**
@@ -409,4 +403,12 @@ public class TableMapReduceUtil {
       job.getClass("mapred.output.format.class", TextOutputFormat.class, OutputFormat.class),
       job.getCombinerClass());
   }
+
+
+  private static int getRegionCount(Configuration conf, TableName tableName) throws IOException {
+    try (Connection conn = ConnectionFactory.createConnection(conf);
+      RegionLocator locator = conn.getRegionLocator(tableName)) {
+      return locator.getAllRegionLocations().size();
+    }
+  }
 }

hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/TableMapReduceUtil.java

@@ -39,7 +39,6 @@ import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.HConstants;
-import org.apache.hadoop.hbase.MetaTableAccessor;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.slf4j.Logger;
@@ -47,6 +46,7 @@ import org.slf4j.LoggerFactory;
 import org.apache.hadoop.hbase.client.Connection;
 import org.apache.hadoop.hbase.client.ConnectionFactory;
 import org.apache.hadoop.hbase.client.Put;
+import org.apache.hadoop.hbase.client.RegionLocator;
 import org.apache.hadoop.hbase.client.Scan;
 import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
 import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
@@ -731,7 +731,7 @@ public class TableMapReduceUtil {
     job.setOutputValueClass(Writable.class);
     if (partitioner == HRegionPartitioner.class) {
       job.setPartitionerClass(HRegionPartitioner.class);
-      int regions = MetaTableAccessor.getRegionCount(conf, TableName.valueOf(table));
+      int regions = getRegionCount(conf, TableName.valueOf(table));
       if (job.getNumReduceTasks() > regions) {
         job.setNumReduceTasks(regions);
       }
@@ -754,13 +754,12 @@ public class TableMapReduceUtil {
    * @param job  The current job to adjust.
    * @throws IOException When retrieving the table details fails.
    */
-  public static void limitNumReduceTasks(String table, Job job)
+  public static void limitNumReduceTasks(String table, Job job) throws IOException {
-  throws IOException {
+    int regions = getRegionCount(job.getConfiguration(), TableName.valueOf(table));
-    int regions =
+    if (job.getNumReduceTasks() > regions) {
-      MetaTableAccessor.getRegionCount(job.getConfiguration(), TableName.valueOf(table));
-    if (job.getNumReduceTasks() > regions)
       job.setNumReduceTasks(regions);
     }
+  }
 
   /**
    * Sets the number of reduce tasks for the given job configuration to the
@@ -770,10 +769,8 @@ public class TableMapReduceUtil {
    * @param job  The current job to adjust.
    * @throws IOException When retrieving the table details fails.
    */
-  public static void setNumReduceTasks(String table, Job job)
+  public static void setNumReduceTasks(String table, Job job) throws IOException {
-  throws IOException {
+    job.setNumReduceTasks(getRegionCount(job.getConfiguration(), TableName.valueOf(table)));
-    job.setNumReduceTasks(MetaTableAccessor.getRegionCount(job.getConfiguration(),
-       TableName.valueOf(table)));
   }
 
   /**
@@ -1057,4 +1054,11 @@ public class TableMapReduceUtil {
 
     return ret;
   }
+
+  private static int getRegionCount(Configuration conf, TableName tableName) throws IOException {
+    try (Connection conn = ConnectionFactory.createConnection(conf);
+      RegionLocator locator = conn.getRegionLocator(tableName)) {
+      return locator.getAllRegionLocations().size();
+    }
+  }
 }

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

@@ -22,7 +22,6 @@ import static org.junit.Assert.assertEquals;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtility;
-import org.apache.hadoop.hbase.MetaTableAccessor;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
 import org.apache.hadoop.hbase.testclassification.MapReduceTests;
@@ -81,14 +80,13 @@ public class TestHRegionPartitioner {
 
   @Test
   public void testHRegionPartitionerMoreRegions() throws Exception {
-
     byte[][] families = { Bytes.toBytes("familyA"), Bytes.toBytes("familyB") };
 
     TableName tableName = TableName.valueOf(name.getMethodName());
     UTIL.createTable(tableName, families, 1, Bytes.toBytes("aa"), Bytes.toBytes("cc"), 5);
 
     Configuration configuration = UTIL.getConfiguration();
-    int numberOfRegions = MetaTableAccessor.getRegionCount(configuration, tableName);
+    int numberOfRegions = UTIL.getMiniHBaseCluster().getRegions(tableName).size();
     assertEquals(5, numberOfRegions);
 
     HRegionPartitioner<Long, Long> partitioner = new HRegionPartitioner<>();

hbase-server/src/main/java/org/apache/hadoop/hbase/util/RegionSplitter.java

@@ -38,7 +38,6 @@ import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.HRegionInfo;
 import org.apache.hadoop.hbase.HRegionLocation;
-import org.apache.hadoop.hbase.MetaTableAccessor;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.client.ColumnFamilyDescriptor;
@@ -414,14 +413,16 @@ public class RegionSplitter {
       if (!conf.getBoolean("split.verify", true)) {
         // NOTE: createTable is synchronous on the table, but not on the regions
         int onlineRegions = 0;
+        try (RegionLocator locator = connection.getRegionLocator(tableName)) {
           while (onlineRegions < splitCount) {
-          onlineRegions = MetaTableAccessor.getRegionCount(connection, tableName);
+            onlineRegions = locator.getAllRegionLocations().size();
             LOG.debug(onlineRegions + " of " + splitCount + " regions online...");
             if (onlineRegions < splitCount) {
               Thread.sleep(10 * 1000); // sleep
             }
           }
         }
+      }
       LOG.debug("Finished creating table with " + splitCount + " regions");
     }
   }

hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestTableFavoredNodes.java

@@ -37,7 +37,6 @@ import org.apache.hadoop.hbase.HBaseTestingUtility;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.HRegionInfo;
 import org.apache.hadoop.hbase.HRegionLocation;
-import org.apache.hadoop.hbase.MetaTableAccessor;
 import org.apache.hadoop.hbase.NamespaceDescriptor;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.TableName;
@@ -247,7 +246,7 @@ public class TestTableFavoredNodes {
     LOG.info("regionA: " + regionA.getEncodedName() + " with FN: " + fnm.getFavoredNodes(regionA));
     LOG.info("regionB: " + regionA.getEncodedName() + " with FN: " + fnm.getFavoredNodes(regionB));
 
-    int countOfRegions = MetaTableAccessor.getRegionCount(TEST_UTIL.getConfiguration(), tableName);
+    int countOfRegions = TEST_UTIL.getMiniHBaseCluster().getRegions(tableName).size();
     admin.mergeRegionsAsync(regionA.getEncodedNameAsBytes(),
         regionB.getEncodedNameAsBytes(), false).get(60, TimeUnit.SECONDS);
 
@@ -393,7 +392,9 @@ public class TestTableFavoredNodes {
     TEST_UTIL.waitFor(WAIT_TIMEOUT, new Waiter.Predicate<Exception>() {
       @Override
       public boolean evaluate() throws Exception {
-        return MetaTableAccessor.getRegionCount(TEST_UTIL.getConfiguration(), tableName) == numRegions;
+        try (RegionLocator locator = TEST_UTIL.getConnection().getRegionLocator(tableName)) {
+          return locator.getAllRegionLocations().size() == numRegions;
+        }
       }
     });
   }

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

@@ -21,6 +21,7 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
+
 import java.io.IOException;
 import java.util.Collections;
 import java.util.Comparator;
@@ -29,7 +30,6 @@ import java.util.concurrent.TimeUnit;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtility;
 import org.apache.hadoop.hbase.HConstants;
-import org.apache.hadoop.hbase.MetaTableAccessor;
 import org.apache.hadoop.hbase.NamespaceDescriptor;
 import org.apache.hadoop.hbase.RegionMetrics;
 import org.apache.hadoop.hbase.ServerName;
@@ -40,6 +40,7 @@ import org.apache.hadoop.hbase.client.Admin;
 import org.apache.hadoop.hbase.client.NormalizeTableFilterParams;
 import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.hbase.client.RegionInfo;
+import org.apache.hadoop.hbase.client.RegionLocator;
 import org.apache.hadoop.hbase.client.Table;
 import org.apache.hadoop.hbase.client.TableDescriptor;
 import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
@@ -155,11 +156,11 @@ public class TestSimpleRegionNormalizerOnCluster {
       assertEquals(
         tn1 + " should have split.",
         tn1RegionCount + 1,
-        MetaTableAccessor.getRegionCount(TEST_UTIL.getConnection(), tn1));
+        getRegionCount(tn1));
       assertEquals(
         tn2 + " should not have split.",
         tn2RegionCount,
-        MetaTableAccessor.getRegionCount(TEST_UTIL.getConnection(), tn2));
+        getRegionCount(tn2));
       waitForTableRegionCount(tn3, tn3RegionCount);
     } finally {
       dropIfExists(tn1);
@@ -195,13 +196,13 @@ public class TestSimpleRegionNormalizerOnCluster {
         assertEquals(
           tableName + " should not have split.",
           currentRegionCount,
-          MetaTableAccessor.getRegionCount(TEST_UTIL.getConnection(), tableName));
+          getRegionCount(tableName));
       } else {
         waitForTableSplit(tableName, currentRegionCount + 1);
         assertEquals(
           tableName + " should have split.",
           currentRegionCount + 1,
-          MetaTableAccessor.getRegionCount(TEST_UTIL.getConnection(), tableName));
+          getRegionCount(tableName));
       }
     } finally {
       dropIfExists(tableName);
@@ -219,7 +220,7 @@ public class TestSimpleRegionNormalizerOnCluster {
       assertEquals(
         tableName + " should have merged.",
         currentRegionCount - 1,
-        MetaTableAccessor.getRegionCount(TEST_UTIL.getConnection(), tableName));
+        getRegionCount(tableName));
     } finally {
       dropIfExists(tableName);
     }
@@ -248,7 +249,7 @@ public class TestSimpleRegionNormalizerOnCluster {
       assertEquals(
         tn1 + " should have split.",
         tn1RegionCount + 1,
-        MetaTableAccessor.getRegionCount(TEST_UTIL.getConnection(), tn1));
+        getRegionCount(tn1));
       waitForTableRegionCount(tn2, tn2RegionCount);
     } finally {
       dropIfExists(tn1);
@@ -277,7 +278,7 @@ public class TestSimpleRegionNormalizerOnCluster {
       assertEquals(
         tn1 + " should have split.",
         tn1RegionCount + 1,
-        MetaTableAccessor.getRegionCount(TEST_UTIL.getConnection(), tn1));
+        getRegionCount(tn1));
       waitForTableRegionCount(tn2, tn2RegionCount);
     } finally {
       dropIfExists(tn1);
@@ -306,7 +307,7 @@ public class TestSimpleRegionNormalizerOnCluster {
       assertEquals(
         tn1 + " should have split.",
         tn1RegionCount + 1,
-        MetaTableAccessor.getRegionCount(TEST_UTIL.getConnection(), tn1));
+        getRegionCount(tn1));
       waitForTableRegionCount(tn2, tn2RegionCount);
     } finally {
       dropIfExists(tn1);
@@ -344,10 +345,10 @@ public class TestSimpleRegionNormalizerOnCluster {
       public String explainFailure() {
         return "expected " + targetRegionCount + " number of regions for table " + tableName;
       }
+
       @Override
       public boolean evaluate() throws IOException {
-        final int currentRegionCount =
+        final int currentRegionCount = getRegionCount(tableName);
-          MetaTableAccessor.getRegionCount(TEST_UTIL.getConnection(), tableName);
         return currentRegionCount == targetRegionCount;
       }
     });
@@ -356,12 +357,14 @@ public class TestSimpleRegionNormalizerOnCluster {
   private static void waitForTableSplit(final TableName tableName, final int targetRegionCount)
       throws IOException {
     TEST_UTIL.waitFor(TimeUnit.MINUTES.toMillis(5), new ExplainingPredicate<IOException>() {
-      @Override public String explainFailure() {
+      @Override
+      public String explainFailure() {
         return "expected normalizer to split region.";
       }
-      @Override public boolean evaluate() throws IOException {
+
-        final int currentRegionCount =
+      @Override
-          MetaTableAccessor.getRegionCount(TEST_UTIL.getConnection(), tableName);
+      public boolean evaluate() throws IOException {
+        final int currentRegionCount = getRegionCount(tableName);
         return currentRegionCount >= targetRegionCount;
       }
     });
@@ -370,12 +373,14 @@ public class TestSimpleRegionNormalizerOnCluster {
   private static void waitForTableMerge(final TableName tableName, final int targetRegionCount)
       throws IOException {
     TEST_UTIL.waitFor(TimeUnit.MINUTES.toMillis(5), new ExplainingPredicate<IOException>() {
-      @Override public String explainFailure() {
+      @Override
+      public String explainFailure() {
         return "expected normalizer to merge regions.";
       }
-      @Override public boolean evaluate() throws IOException {
+
-        final int currentRegionCount =
+      @Override
-          MetaTableAccessor.getRegionCount(TEST_UTIL.getConnection(), tableName);
+      public boolean evaluate() throws IOException {
+        final int currentRegionCount = getRegionCount(tableName);
         return currentRegionCount <= targetRegionCount;
       }
     });
@@ -443,7 +448,7 @@ public class TestSimpleRegionNormalizerOnCluster {
       final boolean normalizerEnabled, final boolean isMergeEnabled)
     throws Exception {
     final List<HRegion> generatedRegions = generateTestData(tableName, 1, 1, 2, 3, 5);
-    assertEquals(5, MetaTableAccessor.getRegionCount(TEST_UTIL.getConnection(), tableName));
+    assertEquals(5, getRegionCount(tableName));
     admin.flush(tableName);
 
     final TableDescriptor td = TableDescriptorBuilder
@@ -481,7 +486,7 @@ public class TestSimpleRegionNormalizerOnCluster {
   private static int createTableBegsMerge(final TableName tableName) throws Exception {
     // create 5 regions with sizes to trigger merge of small regions
     final List<HRegion> generatedRegions = generateTestData(tableName, 1, 1, 3, 3, 5);
-    assertEquals(5, MetaTableAccessor.getRegionCount(TEST_UTIL.getConnection(), tableName));
+    assertEquals(5, getRegionCount(tableName));
     admin.flush(tableName);
 
     final TableDescriptor td = TableDescriptorBuilder
@@ -515,4 +520,10 @@ public class TestSimpleRegionNormalizerOnCluster {
       admin.deleteTable(tableName);
     }
   }
+
+  private static int getRegionCount(TableName tableName) throws IOException {
+    try (RegionLocator locator = TEST_UTIL.getConnection().getRegionLocator(tableName)) {
+      return locator.getAllRegionLocations().size();
+    }
+  }
 }