/*
* Copyright 2008-2013 LinkedIn, Inc
*
* Licensed 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 voldemort.server.rebalance;
import java.io.StringReader;
import java.io.StringWriter;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import voldemort.client.rebalance.RebalanceTaskInfo;
import voldemort.serialization.json.JsonReader;
import voldemort.serialization.json.JsonWriter;
import voldemort.store.metadata.MetadataStore;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
/**
* Store and manipulate rebalancing state. Moved out from
* {@link RebalanceTaskInfo} and {@link MetadataStore}
*
*/
public class RebalancerState {
protected final Map<Integer, RebalanceTaskInfo> stealInfoMap;
public RebalancerState(List<RebalanceTaskInfo> stealInfoList) {
stealInfoMap = Maps.newHashMapWithExpectedSize(stealInfoList.size());
for(RebalanceTaskInfo rebalanceTaskInfo: stealInfoList)
stealInfoMap.put(rebalanceTaskInfo.getDonorId(), rebalanceTaskInfo);
}
public static RebalancerState create(String json) {
List<RebalanceTaskInfo> stealInfoList = Lists.newLinkedList();
JsonReader reader = new JsonReader(new StringReader(json));
for(Object o: reader.readArray()) {
Map<?, ?> m = (Map<?, ?>) o;
stealInfoList.add(RebalanceTaskInfo.create(m));
}
return new RebalancerState(stealInfoList);
}
public String toJsonString() {
List<Map<String, Object>> maps = Lists.newLinkedList();
for(RebalanceTaskInfo rebalanceTaskInfo: stealInfoMap.values())
maps.add(rebalanceTaskInfo.asMap());
StringWriter stringWriter = new StringWriter();
new JsonWriter(stringWriter).write(maps);
stringWriter.flush();
return stringWriter.toString();
}
public boolean isEmpty() {
return stealInfoMap.isEmpty();
}
public boolean remove(RebalanceTaskInfo rebalanceTaskInfo) {
RebalanceTaskInfo prev = stealInfoMap.remove(rebalanceTaskInfo.getDonorId());
return prev != null;
}
public boolean update(RebalanceTaskInfo rebalanceTaskInfo) {
if(stealInfoMap.containsKey(rebalanceTaskInfo.getDonorId()))
return false;
stealInfoMap.put(rebalanceTaskInfo.getDonorId(), rebalanceTaskInfo);
return true;
}
public Collection<RebalanceTaskInfo> getAll() {
return stealInfoMap.values();
}
public RebalanceTaskInfo find(int donorId) {
return stealInfoMap.get(donorId);
}
@Override
public boolean equals(Object o) {
if(this == o)
return true;
if(o == null || getClass() != o.getClass())
return false;
RebalancerState that = (RebalancerState) o;
if(!stealInfoMap.equals(that.stealInfoMap))
return false;
return true;
}
@Override
public int hashCode() {
return stealInfoMap.hashCode();
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder("RebalancerState(operations: ");
sb.append("\n");
for(RebalanceTaskInfo info: getAll()) {
sb.append(info);
sb.append("\n");
}
sb.append(")");
return sb.toString();
}
}