diff --git a/CHANGES.txt b/CHANGES.txt index 33148801ec6..825fba16e07 100644 --- a/CHANGES.txt +++ b/CHANGES.txt @@ -198,6 +198,7 @@ Release 0.20.0 - Unreleased HBASE-889 The current Thrift API does not allow a new scanner to be created without supplying a column list unlike the other APIs. (Tim Sell via Stack) + HBASE-1341 HTable pooler Release 0.19.0 - 01/21/2009 INCOMPATIBLE CHANGES diff --git a/src/java/org/apache/hadoop/hbase/client/HTablePool.java b/src/java/org/apache/hadoop/hbase/client/HTablePool.java new file mode 100755 index 00000000000..301982e43f1 --- /dev/null +++ b/src/java/org/apache/hadoop/hbase/client/HTablePool.java @@ -0,0 +1,127 @@ +/** + * Copyright 2009 The Apache Software Foundation + * + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.apache.hadoop.hbase.client; + +import java.io.IOException; +import java.util.ArrayDeque; +/* using a stack instead of a FIFO might have some small positive performance + impact wrt. cache */ +import java.util.Deque; +import java.util.Map; +import java.util.TreeMap; + +import org.apache.hadoop.hbase.util.Bytes; + +/** + * A simple pool of HTable instances. + *
+ * The default pool size is 10.
+ */
+public class HTablePool {
+ private static final Map
+ * NOTE: maxSize is advisory. If the pool does not yet exist, a new
+ * shared pool will be allocated with maxSize as the size limit.
+ * However, if the shared pool already exists, and was created with a
+ * different (or default) value for maxSize, it will not be changed.
+ * @param tableName the table name
+ * @param maxSize the maximum size of the pool
+ * @return the table pool
+ */
+ public static HTablePool getPool(byte[] tableName, int maxSize) {
+ synchronized (poolMap) {
+ HTablePool pool = poolMap.get(tableName);
+ if (pool == null) {
+ pool = new HTablePool(tableName, maxSize);
+ poolMap.put(tableName, pool);
+ }
+ return pool;
+ }
+ }
+
+ /**
+ * Constructor
+ * @param tableName the table name
+ */
+ public HTablePool(byte[] tableName) {
+ this.tableName = tableName;
+ this.maxSize = 10;
+ this.pool = new ArrayDeque