/*
* Copyright (c) 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017 David Berkman
*
* This file is part of the SmallMind Code Project.
*
* The SmallMind Code Project is free software, you can redistribute
* it and/or modify it under either, at your discretion...
*
* 1) The terms of GNU Affero General Public License as published by the
* Free Software Foundation, either version 3 of the License, or (at
* your option) any later version.
*
* ...or...
*
* 2) The terms of the Apache License, Version 2.0.
*
* The SmallMind Code Project is distributed in the hope that it will
* be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License or Apache License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* and the Apache License along with the SmallMind Code Project. If not, see
* <http://www.gnu.org/licenses/> or <http://www.apache.org/licenses/LICENSE-2.0>.
*
* Additional permission under the GNU Affero GPL version 3 section 7
* ------------------------------------------------------------------
* If you modify this Program, or any covered work, by linking or
* combining it with other code, such other code is not for that reason
* alone subject to any of the requirements of the GNU Affero GPL
* version 3.
*/
package org.smallmind.memcached;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.atomic.AtomicLong;
public class InMemoryMemcachedClient implements ProxyMemcachedClient {
private HashMap<String, Holder<?>> internalMap = new HashMap<>();
private AtomicLong counter = new AtomicLong(0);
public long getOpTimeout () {
return 5000L;
}
@Override
public <T> ProxyCASResponse<T> createCASResponse (long cas, T value) {
return new InMemoryCASResponse<>(cas, value);
}
@Override
public synchronized <T> T get (String key) {
Holder<T> holder;
if (((holder = (Holder<T>)internalMap.get(key)) == null) || holder.isExpired()) {
return null;
}
return holder.getValue();
}
@Override
public synchronized <T> Map<String, T> get (Collection<String> keys) {
Map<String, T> resultMap = new HashMap<>();
for (String key : keys) {
T result;
if ((result = get(key)) != null) {
resultMap.put(key, result);
}
}
return resultMap;
}
@Override
public synchronized <T> ProxyCASResponse<T> casGet (String key) {
Holder<T> holder;
if (((holder = (Holder<T>)internalMap.get(key)) == null) || holder.isExpired()) {
return null;
}
return new InMemoryCASResponse<T>(holder.getCas(), holder.getValue());
}
@Override
public synchronized <T> boolean set (String key, int expiration, T value) {
internalMap.put(key, new Holder<>(expiration, value));
return true;
}
@Override
public synchronized <T> boolean casSet (String key, int expiration, T value, long cas) {
Holder<T> holder;
if (((holder = (Holder<T>)internalMap.get(key)) == null) || holder.isExpired()) {
internalMap.put(key, new Holder(expiration, value));
return true;
} else if (cas == holder.getCas()) {
internalMap.put(key, new Holder<>(expiration, value));
return true;
}
return false;
}
@Override
public synchronized boolean delete (String key) {
internalMap.remove(key);
return true;
}
@Override
public synchronized boolean casDelete (String key, long cas) {
Holder holder;
if (((holder = internalMap.get(key)) == null) || holder.isExpired()) {
return true;
} else if (cas == holder.getCas()) {
internalMap.remove(key);
return true;
}
return false;
}
@Override
public synchronized boolean touch (String key, int expiration) {
Holder<?> holder;
if (((holder = internalMap.get(key)) == null) || holder.isExpired()) {
return false;
}
holder.touch(expiration);
return true;
}
@Override
public synchronized <T> T getAndTouch (String key, int expiration) {
Holder<T> holder;
if (((holder = (Holder<T>)internalMap.get(key)) == null) || holder.isExpired()) {
return null;
}
holder.touch(expiration);
return holder.getValue();
}
@Override
public void clear () {
internalMap.clear();
}
@Override
public void shutdown () {
}
private class Holder<T> {
private T value;
private long cas;
private long creation;
private int expiration;
public Holder (int expiration, T value) {
if (expiration < 0) {
throw new IllegalArgumentException();
}
this.expiration = expiration;
this.value = value;
cas = counter.incrementAndGet();
creation = System.currentTimeMillis();
}
public T getValue () {
return value;
}
public long getCas () {
return cas;
}
public void touch (int expiration) {
this.expiration = expiration;
creation = System.currentTimeMillis();
}
public boolean isExpired () {
return (expiration > 0) && System.currentTimeMillis() >= creation + (expiration * 1000);
}
}
}