Github user joshelser commented on a diff in the pull request:
https://github.com/apache/accumulo/pull/16#discussion_r18073654
--- Diff:
server/base/src/main/java/org/apache/accumulo/server/fs/GeneralVolumeChooser.java
---
@@ -0,0 +1,60 @@
+/*
+ * 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.accumulo.server.fs;
+
+import java.util.Map;
+
+import org.apache.accumulo.core.conf.AccumuloConfiguration.AllFilter;
+import org.apache.accumulo.core.conf.AccumuloConfiguration.PropertyFilter;
+import org.apache.accumulo.start.classloader.vfs.AccumuloVFSClassLoader;
+import org.apache.log4j.Logger;
+
+public class GeneralVolumeChooser implements VolumeChooser {
+ private static final Logger log =
Logger.getLogger(GeneralVolumeChooser.class);
+
+ public GeneralVolumeChooser() {}
+
+ @Override
+ public String choose(VolumeChooserEnvironment env, String[] options) {
+ String clazzName = new String();
+ try {
+ // Get the current table's properties, and find the chooser property
+ PropertyFilter filter = new AllFilter();
+ Map<String,String> props = new java.util.HashMap<String,String>();
+ env.getProperties(props, filter);
+
+ clazzName = props.get("table.custom.chooser");
+ log.info("TableID: " + env.getTableId() + " ClassName: " +
clazzName);
+
+ // Load the correct chooser and create an instance of it
+ Class<? extends VolumeChooser> clazz =
AccumuloVFSClassLoader.loadClass(clazzName, VolumeChooser.class);
--- End diff --
This is going to be rather expensive to load the class and instantiate it
every single time we choose a volume for a file WRT how quick it should be.
Make sure the implementations are thread-safe and aren't sharing state and you
can keep a cache of implementations around. (although this has issues when
considering dynamic classloading)
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---
