BLUR-273: Implement SnapshotDeletionPolicy to load old snapshots
Signed-off-by: Aaron McCurry <amccurry@gmail.com>
diff --git a/blur-core/src/main/java/org/apache/blur/manager/writer/BlurSnapshotDeletionPolicy.java b/blur-core/src/main/java/org/apache/blur/manager/writer/BlurSnapshotDeletionPolicy.java
index f19262f..c3b98b7 100644
--- a/blur-core/src/main/java/org/apache/blur/manager/writer/BlurSnapshotDeletionPolicy.java
+++ b/blur-core/src/main/java/org/apache/blur/manager/writer/BlurSnapshotDeletionPolicy.java
@@ -1,5 +1,21 @@
package org.apache.blur.manager.writer;
+/**
+ * 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.
+ */
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
@@ -9,6 +25,10 @@
import org.apache.lucene.index.SnapshotDeletionPolicy;
import org.apache.lucene.store.Directory;
+/**
+ * This class extends {@link SnapshotDeletionPolicy}. It loads the old snapshots
+ * and also contain a map of snapshot file name and corresponding generation.
+ */
public class BlurSnapshotDeletionPolicy extends SnapshotDeletionPolicy {
public static final String SNAPSHOTS_PREFIX = "_snapshot";
@@ -48,12 +68,6 @@
mapOfSnapshotNameGen.remove(snapshotName);
}
- /**
- * Reads the snapshots information from the given {@link Directory}. This
- * method can be used if the snapshots information is needed, however you
- * cannot instantiate the deletion policy (because e.g., some other process
- * keeps a lock on the snapshots directory).
- */
private synchronized void loadPriorSnapshots() throws IOException {
long genLoaded = -1;
for (String file : dir.listAll()) {
