/*
* Copyright (c) 2013 Hudson.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Roy Varghese
*/
package hudson.model;
import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import com.google.common.cache.RemovalListener;
import com.google.common.cache.RemovalNotification;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import org.slf4j.LoggerFactory;
/**
* A cache for {@link TopLevelItems} object that are directly held by
* the {@link Hudson} instance.
*
* This class is package private.
*
* @author Roy Varghese
*/
class TopLevelItemsCache {
// Cache parameters
// Seconds after which items in cache are removed. Time is reset on access.
private static int EVICT_IN_SECONDS;
// Initial cache capacity
private static int INITIAL_CAPACITY;
// Maximum number of cached entries.
private static int MAX_ENTRIES;
// Initialize from system properties if available
{
Integer val;
val = Integer.getInteger("hudson.jobs.cache.evict_in_seconds");
EVICT_IN_SECONDS = val == null? 60: val;
val = Integer.getInteger("hudson.jobs.cache.initial_capacity");
INITIAL_CAPACITY = val == null ? 1024: val;
val = Integer.getInteger("hudson.jobs.cache.max_entries");
MAX_ENTRIES = val == null ? 1024 : val;
}
final LoadingCache<LazyTopLevelItem.Key, TopLevelItem> cache;
TopLevelItemsCache() {
cache = CacheBuilder.newBuilder()
.initialCapacity(INITIAL_CAPACITY)
.expireAfterAccess(EVICT_IN_SECONDS, TimeUnit.SECONDS)
.maximumSize(MAX_ENTRIES)
.softValues()
.removalListener(new RemovalListener<LazyTopLevelItem.Key, TopLevelItem>() {
@Override
public void onRemoval(RemovalNotification<LazyTopLevelItem.Key, TopLevelItem> notification) {
// System.out.println("*** Removed from cache " + notification.getKey().name );
}
})
.build(new CacheLoader<LazyTopLevelItem.Key, TopLevelItem>() {
Map<String, Integer> map = new HashMap<String, Integer>();
@Override
public TopLevelItem load(LazyTopLevelItem.Key key) throws Exception {
try {
TopLevelItem item = (TopLevelItem) key.configFile.read();
item.onLoad(key.parent, key.name);
key.clearLoadErrorFlag();
return item;
}
catch (Throwable ex) {
System.err.println("ERROR===: Unable to load " +key.name);
key.setLoadErrorFlag();
return new BrokenTopLevelItem(key, ex);
}
}
});
}
TopLevelItem get(LazyTopLevelItem.Key key) {
try {
return cache.get(key);
} catch (ExecutionException ex) {
LoggerFactory.getLogger(TopLevelItemsCache.class.getName()).error("Error when retrieving item from cache", ex);
return null;
}
}
void put(LazyTopLevelItem.Key key, TopLevelItem item) {
cache.put(key, item);
}
}