/*
* 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.jackrabbit.core.query.lucene;
import org.apache.lucene.index.IndexDeletionPolicy;
import org.apache.lucene.index.IndexCommit;
import org.apache.lucene.store.Directory;
import java.util.List;
import java.io.IOException;
/**
* <code>IndexDeletionPolicyImpl</code>...
*/
public class IndexDeletionPolicyImpl implements IndexDeletionPolicy {
private static final String SEGMENTS = "segments";
private final PersistentIndex index;
private final long maxAge;
public IndexDeletionPolicyImpl(PersistentIndex index, long maxAge)
throws IOException {
this.index = index;
this.maxAge = maxAge;
// read current generation
readCurrentGeneration();
}
public void onInit(List commits) throws IOException {
checkCommits(commits);
}
public void onCommit(List commits) throws IOException {
checkCommits(commits);
// report back current generation
IndexCommit current = (IndexCommit) commits.get(commits.size() - 1);
String name = current.getSegmentsFileName();
if (name.equals(SEGMENTS)) {
index.setCurrentGeneration(0);
} else {
index.setCurrentGeneration(
Long.parseLong(name.substring(SEGMENTS.length() + 1),
Character.MAX_RADIX));
}
}
//-------------------------------< internal >-------------------------------
private void checkCommits(List commits) throws IOException {
long currentTime = System.currentTimeMillis();
for (int i = 0; i < commits.size() - 1; i++) {
IndexCommit ic = (IndexCommit) commits.get(i);
long lastModified = index.getDirectory().fileModified(ic.getSegmentsFileName());
if (currentTime - lastModified > maxAge) {
ic.delete();
} else {
// following commits are younger, no need to check
break;
}
}
}
void readCurrentGeneration() throws IOException {
Directory dir = index.getDirectory();
String[] names = dir.list();
long max = 0;
if (names != null) {
for (String name : names) {
long gen = -1;
if (name.startsWith(SEGMENTS)) {
if (name.length() == SEGMENTS.length()) {
gen = 0;
} else if (name.charAt(SEGMENTS.length()) == '_') {
gen = Long.parseLong(name.substring(SEGMENTS.length() + 1), Character.MAX_RADIX);
}
}
if (gen > max) {
max = gen;
}
}
}
index.setCurrentGeneration(max);
}
}