/*
* Cloud9: A MapReduce Library for Hadoop
*
* 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 edu.umd.cloud9.util.fd;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import com.google.common.collect.Lists;
import edu.umd.cloud9.io.pair.PairOfIntLong;
import edu.umd.cloud9.util.map.HMapIL;
import edu.umd.cloud9.util.map.MapIL;
/**
* Implementation of {@link Int2LongFrequencyDistribution} based on {@link HMapIL}.
*
* @author Jimmy Lin
*/
public class Int2LongFrequencyDistributionEntry implements Int2LongFrequencyDistribution {
private HMapIL counts = new HMapIL();
private long sumOfCounts = 0;
@Override
public void increment(int key) {
if (contains(key)) {
set(key, get(key) + 1L);
} else {
set(key, 1L);
}
}
@Override
public void increment(int key, long cnt) {
if (contains(key)) {
set(key, get(key) + cnt);
} else {
set(key, cnt);
}
}
@Override
public void decrement(int key) {
if (contains(key)) {
long v = get(key);
if (v == 1L) {
remove(key);
} else {
set(key, v - 1L);
}
} else {
throw new RuntimeException("Can't decrement non-existent event!");
}
}
@Override
public void decrement(int key, long cnt) {
if (contains(key)) {
long v = get(key);
if (v < cnt) {
throw new RuntimeException("Can't decrement past zero!");
} else if (v == cnt) {
remove(key);
} else {
set(key, v - cnt);
}
} else {
throw new RuntimeException("Can't decrement non-existent event!");
}
}
@Override
public boolean contains(int key) {
return counts.containsKey(key);
}
@Override
public long get(int key) {
return counts.get(key);
}
@Override
public double computeRelativeFrequency(int k) {
return (double) counts.get(k) / getSumOfCounts();
}
@Override
public double computeLogRelativeFrequency(int k) {
return Math.log(counts.get(k)) - Math.log(getSumOfCounts());
}
@Override
public long set(int k, long v) {
long rv = counts.put(k, v);
sumOfCounts = sumOfCounts - rv + v;
return rv;
}
@Override
public long remove(int k) {
long rv = counts.remove(k);
sumOfCounts -= rv;
return rv;
}
@Override
public void clear() {
counts.clear();
sumOfCounts = 0;
}
@Override
public int getNumberOfEvents() {
return counts.size();
}
@Override
public long getSumOfCounts() {
return sumOfCounts;
}
/**
* Iterator returns the same object every time, just with a different payload.
*/
public Iterator<PairOfIntLong> iterator() {
return new Iterator<PairOfIntLong>() {
private Iterator<MapIL.Entry> iter =
Int2LongFrequencyDistributionEntry.this.counts.entrySet().iterator();
private final PairOfIntLong pair = new PairOfIntLong();
@Override
public boolean hasNext() {
return iter.hasNext();
}
@Override
public PairOfIntLong next() {
if (!hasNext()) {
return null;
}
MapIL.Entry entry = iter.next();
pair.set(entry.getKey(), entry.getValue());
return pair;
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
};
}
@Override
public List<PairOfIntLong> getEntries(Order ordering) {
if (ordering.equals(Order.ByRightElementDescending)) {
return getEntriesSorted(comparatorRightDescending);
} else if (ordering.equals(Order.ByLeftElementAscending)) {
return getEntriesSorted(comparatorLeftAscending);
} else if (ordering.equals(Order.ByRightElementAscending)) {
return getEntriesSorted(comparatorRightAscending);
} else if (ordering.equals(Order.ByLeftElementDescending)) {
return getEntriesSorted(comparatorLeftDescending);
}
// Should never get here.
return null;
}
@Override
public List<PairOfIntLong> getEntries(Order ordering, int n) {
if (ordering.equals(Order.ByRightElementDescending)) {
return getEntriesSorted(comparatorRightDescending, n);
} else if (ordering.equals(Order.ByLeftElementAscending)) {
return getEntriesSorted(comparatorLeftAscending, n);
} else if (ordering.equals(Order.ByRightElementAscending)) {
return getEntriesSorted(comparatorRightAscending, n);
} else if (ordering.equals(Order.ByLeftElementDescending)) {
return getEntriesSorted(comparatorLeftDescending, n);
}
// Should never get here.
return null;
}
private final Comparator<PairOfIntLong> comparatorRightDescending =
new Comparator<PairOfIntLong>() {
public int compare(PairOfIntLong e1, PairOfIntLong e2) {
if (e1.getRightElement() > e2.getRightElement()) {
return -1;
}
if (e1.getRightElement() < e2.getRightElement()) {
return 1;
}
if (e1.getLeftElement() == e2.getLeftElement()) {
throw new RuntimeException("Event observed twice!");
}
return e1.getLeftElement() < e2.getLeftElement() ? -1 : 1;
}
};
private final Comparator<PairOfIntLong> comparatorRightAscending =
new Comparator<PairOfIntLong>() {
public int compare(PairOfIntLong e1, PairOfIntLong e2) {
if (e1.getRightElement() > e2.getRightElement()) {
return 1;
}
if (e1.getRightElement() < e2.getRightElement()) {
return -1;
}
if (e1.getLeftElement() == e2.getLeftElement()) {
throw new RuntimeException("Event observed twice!");
}
return e1.getLeftElement() < e2.getLeftElement() ? -1 : 1;
}
};
private final Comparator<PairOfIntLong> comparatorLeftAscending =
new Comparator<PairOfIntLong>() {
public int compare(PairOfIntLong e1, PairOfIntLong e2) {
if (e1.getLeftElement() > e2.getLeftElement()) {
return 1;
}
if (e1.getLeftElement() < e2.getLeftElement()) {
return -1;
}
throw new RuntimeException("Event observed twice!");
}
};
private final Comparator<PairOfIntLong> comparatorLeftDescending =
new Comparator<PairOfIntLong>() {
public int compare(PairOfIntLong e1, PairOfIntLong e2) {
if (e1.getLeftElement() > e2.getLeftElement()) {
return -1;
}
if (e1.getLeftElement() < e2.getLeftElement()) {
return 1;
}
throw new RuntimeException("Event observed twice!");
}
};
private List<PairOfIntLong> getEntriesSorted(Comparator<PairOfIntLong> comparator) {
List<PairOfIntLong> list = Lists.newArrayList();
for (MapIL.Entry e : counts.entrySet()) {
list.add(new PairOfIntLong(e.getKey(), e.getValue()));
}
Collections.sort(list, comparator);
return list;
}
private List<PairOfIntLong> getEntriesSorted(Comparator<PairOfIntLong> comparator, int n) {
List<PairOfIntLong> list = getEntriesSorted(comparator);
return list.subList(0, n);
}
}