HBASE-2435 HTablePool - method to release resources after use

git-svn-id: https://svn.apache.org/repos/asf/hadoop/hbase/trunk@933438 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -497,6 +497,8 @@ Release 0.21.0 - Unreleased
                (Todd Lipcon via Stack)
    HBASE-2423  Update 'Getting Started' for 0.20.4 including making
                "important configurations more visiable"
+   HBASE-2435  HTablePool - method to release resources after use
+               (Kay Kay via Stack)
 
   NEW FEATURES
    HBASE-1961  HBase EC2 scripts

core/src/main/java/org/apache/hadoop/hbase/client/HTableFactory.java

@@ -39,4 +39,17 @@ public class HTableFactory implements HTableInterfaceFactory {
       throw new RuntimeException(ioe);
     }
   }
+
+  @Override
+  public void releaseHTableInterface(HTableInterface table) {
+    try { 
+      table.close();
+    } catch (IOException ioe) {
+      throw new RuntimeException(ioe);
+    }
+    
+  }
+  
+  
+  
 }

core/src/main/java/org/apache/hadoop/hbase/client/HTableInterfaceFactory.java

@@ -37,4 +37,11 @@ public interface HTableInterfaceFactory {
    * @return HTableInterface instance.
    */
   HTableInterface createHTableInterface(Configuration config, byte[] tableName);
+  
+  
+  /**
+   * Release the HTable resource represented by the table.
+   * @param table
+   */
+  void releaseHTableInterface(final HTableInterface table);
 }

core/src/main/java/org/apache/hadoop/hbase/client/HTablePool.java

@@ -27,6 +27,7 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.LinkedList;
 import java.util.Map;
+import java.util.Queue;
 
 /**
  * A simple pool of HTable instances.<p>
@@ -124,4 +125,41 @@ public class HTablePool {
   protected HTableInterface createHTable(String tableName) {
     return this.tableFactory.createHTableInterface(config, Bytes.toBytes(tableName));
   }
+  
+  /**
+   * Closes all the HTable instances , belonging to the given table, in the table pool.
+   * <p>
+   * Note: this is a 'shutdown' of the given table pool and different from 
+   * {@link #putTable(HTableInterface)}, that is used to return the table 
+   * instance to the pool for future re-use.
+   *  
+   * @param tableName 
+   */
+  public void closeTablePool(final String tableName)  {
+    Queue<HTableInterface> queue = tables.get(tableName);
+    synchronized (queue) {
+      HTableInterface table = queue.poll();
+      while (table != null) {
+        this.tableFactory.releaseHTableInterface(table);
+        table = queue.poll();
+      }
+    }
+
+  }
+
+  /**
+   * See {@link #closeTablePool(String)}.
+   * 
+   * @param tableName
+   */
+  public void closeTablePool(final byte[] tableName)  {
+    closeTablePool(Bytes.toString(tableName));
+  }
+
+  int getCurrentPoolSize(String tableName) {
+    Queue<HTableInterface> queue = tables.get(tableName);
+    synchronized(queue) {
+      return queue.size();
+    }
+  }  
 }

core/src/test/java/org/apache/hadoop/hbase/client/TestHTablePool.java

@@ -19,47 +19,73 @@
  */
 package org.apache.hadoop.hbase.client;
 
+import java.io.IOException;
+
+import junit.framework.Assert;
+
 import org.apache.hadoop.hbase.HBaseConfiguration;
-import org.apache.hadoop.hbase.HBaseTestCase;
+import org.apache.hadoop.hbase.HBaseTestingUtility;
+import org.apache.hadoop.hbase.HColumnDescriptor;
+import org.apache.hadoop.hbase.HTableDescriptor;
+import org.apache.hadoop.hbase.MasterNotRunningException;
 import org.apache.hadoop.hbase.util.Bytes;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
 
 /**
  * Tests HTablePool.
  */
-public class TestHTablePool extends HBaseTestCase {
+public class TestHTablePool  {
 
+  private static HBaseTestingUtility TEST_UTIL   =  new HBaseTestingUtility();
+  
+  @BeforeClass
+  public static void beforeClass() throws Exception { 
+    TEST_UTIL.startMiniCluster(1);
+
+  }
+  
+  @AfterClass
+  public static void afterClass() throws IOException { 
+    TEST_UTIL.shutdownMiniCluster();
+  }
+  
+  @Test
   public void testTableWithStringName() {
     HTablePool pool = new HTablePool((HBaseConfiguration)null, Integer.MAX_VALUE);
     String tableName = "testTable";
 
     // Request a table from an empty pool
     HTableInterface table = pool.getTable(tableName);
-    assertNotNull(table);
+    Assert.assertNotNull(table);
 
     // Return the table to the pool
     pool.putTable(table);
 
     // Request a table of the same name
     HTableInterface sameTable = pool.getTable(tableName);
-    assertSame(table, sameTable);
+    Assert.assertSame(table, sameTable);
   }
 
+  @Test
   public void testTableWithByteArrayName() {
     HTablePool pool = new HTablePool((HBaseConfiguration)null, Integer.MAX_VALUE);
     byte[] tableName = Bytes.toBytes("testTable");
 
     // Request a table from an empty pool
     HTableInterface table = pool.getTable(tableName);
-    assertNotNull(table);
+    Assert.assertNotNull(table);
 
     // Return the table to the pool
     pool.putTable(table);
 
     // Request a table of the same name
     HTableInterface sameTable = pool.getTable(tableName);
-    assertSame(table, sameTable);
+    Assert.assertSame(table, sameTable);
   }
 
+  @Test
   public void testTableWithMaxSize() {
     HTablePool pool = new HTablePool((HBaseConfiguration)null, 2);
     String tableName = "testTable";
@@ -79,11 +105,12 @@ public class TestHTablePool extends HBaseTestCase {
     HTableInterface sameTable1 = pool.getTable(tableName);
     HTableInterface sameTable2 = pool.getTable(tableName);
     HTableInterface sameTable3 = pool.getTable(tableName);
-    assertSame(table1, sameTable1);
-    assertSame(table2, sameTable2);
-    assertNotSame(table3, sameTable3);
+    Assert.assertSame(table1, sameTable1);
+    Assert.assertSame(table2, sameTable2);
+    Assert.assertNotSame(table3, sameTable3);
   }
 
+  @Test
   public void testTablesWithDifferentNames() {
     HTablePool pool = new HTablePool((HBaseConfiguration)null, Integer.MAX_VALUE);
     String tableName1 = "testTable1";
@@ -92,7 +119,7 @@ public class TestHTablePool extends HBaseTestCase {
     // Request a table from an empty pool
     HTableInterface table1 = pool.getTable(tableName1);
     HTableInterface table2 = pool.getTable(tableName2);
-    assertNotNull(table2);
+    Assert.assertNotNull(table2);
 
     // Return the tables to the pool
     pool.putTable(table1);
@@ -101,7 +128,45 @@ public class TestHTablePool extends HBaseTestCase {
     // Request tables of the same names
     HTableInterface sameTable1 = pool.getTable(tableName1);
     HTableInterface sameTable2 = pool.getTable(tableName2);
-    assertSame(table1, sameTable1);
-    assertSame(table2, sameTable2);
+    Assert.assertSame(table1, sameTable1);
+    Assert.assertSame(table2, sameTable2);
+  }
+  
+  
+  @Test
+  public void testCloseTablePool() throws IOException { 
+    
+    HTablePool pool = new HTablePool(TEST_UTIL.getConfiguration(), 4);
+    String tableName = "testTable";
+    HBaseAdmin admin = new HBaseAdmin(TEST_UTIL.getConfiguration());
+
+    if (admin.tableExists(tableName)) {
+      admin.deleteTable(tableName);
+    }
+
+    HTableDescriptor tableDescriptor = new HTableDescriptor(Bytes
+        .toBytes(tableName));
+    tableDescriptor.addFamily(new HColumnDescriptor("randomFamily"));
+    admin.createTable(tableDescriptor);
+
+    
+    // Request tables from an empty pool
+    HTableInterface[] tables = new HTableInterface[4];
+    for (int i = 0; i < 4; ++i ) {
+      tables[i] = pool.getTable(tableName);
+    }
+    
+    pool.closeTablePool(tableName);
+    
+    for (int i = 0; i < 4; ++i ) {
+      pool.putTable(tables[i]);
+    }
+
+    Assert.assertEquals(4, pool.getCurrentPoolSize(tableName));
+    
+    pool.closeTablePool(tableName);
+
+    Assert.assertEquals(0, pool.getCurrentPoolSize(tableName));
+    
   }
 }