/*
* Copyright 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.utils;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.TreeSet;
import voldemort.VoldemortException;
/**
* Two dimensional counter. Currently used to count moves in a rebalancing plan.
* The toString method is tailored to this use case. The structure may be
* generally useful though, the 'indices' is hard-coded to be an Integer at this
* time.
*
*/
public class MoveMap {
final TreeSet<Integer> idKeySet;
final Map<Integer, Map<Integer, Integer>> fromToMoves;
public MoveMap(Set<Integer> ids) {
idKeySet = new TreeSet<Integer>(ids);
fromToMoves = new HashMap<Integer, Map<Integer, Integer>>();
for(Integer fromId: ids) {
fromToMoves.put(fromId, new HashMap<Integer, Integer>());
for(Integer toId: ids) {
fromToMoves.get(fromId).put(toId, new Integer(0));
}
}
}
public int increment(int fromId, int toId) {
return this.add(fromId, toId, 1);
}
public int add(int fromId, int toId, int amount) {
int moves = fromToMoves.get(fromId).get(toId);
moves += amount;
fromToMoves.get(fromId).put(toId, moves);
return moves;
}
public int get(int fromId, int toId) {
return fromToMoves.get(fromId).get(toId);
}
public void add(MoveMap rhs) {
if(!idKeySet.containsAll(rhs.idKeySet) || !rhs.idKeySet.containsAll(idKeySet)) {
throw new VoldemortException("MoveMap objects cannot be added! They have incompatible id sets ("
+ idKeySet + " vs. " + rhs.idKeySet + ").");
}
for(Integer fromId: idKeySet) {
for(Integer toId: idKeySet) {
int moves = get(fromId, toId) + rhs.get(fromId, toId);
fromToMoves.get(fromId).put(toId, moves);
}
}
}
public Map<Integer, Integer> groupByFrom() {
Map<Integer, Integer> groupByFrom = new HashMap<Integer, Integer>();
for(Integer id: idKeySet) {
groupByFrom.put(id, 0);
}
for(Integer fromId: idKeySet) {
for(Integer toId: idKeySet) {
int moves = get(fromId, toId) + groupByFrom.get(fromId);
groupByFrom.put(fromId, moves);
}
}
return groupByFrom;
}
public Map<Integer, Integer> groupByTo() {
Map<Integer, Integer> groupByTo = new HashMap<Integer, Integer>();
for(Integer id: idKeySet) {
groupByTo.put(id, 0);
}
for(Integer fromId: idKeySet) {
for(Integer toId: idKeySet) {
int moves = get(fromId, toId) + groupByTo.get(toId);
groupByTo.put(toId, moves);
}
}
return groupByTo;
}
public String toFlowString() {
StringBuilder sb = new StringBuilder();
Map<Integer, Integer> froms = groupByFrom();
Map<Integer, Integer> tos = groupByTo();
for(Integer id: idKeySet) {
sb.append(String.format("%6d", tos.get(id)) + " -> (" + String.format("%4d", id)
+ ") -> " + String.format("%6d", froms.get(id)) + "\n");
}
return sb.toString();
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
for(Integer fromId: idKeySet) {
for(Integer toId: idKeySet) {
sb.append("(" + String.format("%4d", fromId) + ") -> ("
+ String.format("%4d", toId) + ") = "
+ String.format("%6d", fromToMoves.get(fromId).get(toId)) + "\n");
}
}
return sb.toString();
}
}