org.elasticsearch.xpack.core.watcher.common.stats.Counters Maven / Gradle / Ivy
/*
* Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
* or more contributor license agreements. Licensed under the Elastic License
* 2.0; you may not use this file except in compliance with the Elastic License
* 2.0.
*/
package org.elasticsearch.xpack.core.watcher.common.stats;
import com.carrotsearch.hppc.ObjectLongHashMap;
import com.carrotsearch.hppc.cursors.ObjectLongCursor;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.io.stream.Writeable;
import java.io.IOException;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* Helper class to create simple usage stat counters based on longs
* Internally this is a map mapping from String to a long, which is the counter
* Calling toNestedMap() will create a nested map, where each dot of the key name will nest deeper
* The main reason for this class is that the stats producer should not be worried about how the map is actually nested
*/
public class Counters implements Writeable {
private ObjectLongHashMap counters = new ObjectLongHashMap<>();
public Counters(StreamInput in) throws IOException {
int counters = in.readVInt();
for (int i = 0; i < counters; i++) {
inc(in.readString(), in.readVLong());
}
}
public Counters(String ... names) {
for (String name : names) {
set(name);
}
}
/**
* Sets a counter. This ensures that the counter is there, even though it is never incremented.
* @param name Name of the counter
*/
public void set(String name) {
counters.put(name, 0);
}
/**
* Increment the counter by one
* @param name Name of the counter
*/
public void inc(String name) {
inc(name, 1);
}
/**
* Increment the counter by configured number
* @param name The name of the counter
* @param count Incremental value
*/
public void inc(String name, long count) {
counters.addTo(name, count);
}
public long get(String name) {
return counters.get(name);
}
public long size() {
return counters.size();
}
public boolean hasCounters() {
return size() > 0;
}
/**
* Convert the counters to a nested map, using the "." as a splitter to create deeper maps
* @return A nested map with all the current configured counters
*/
@SuppressWarnings("unchecked")
public Map toNestedMap() {
Map map = new HashMap<>();
for (ObjectLongCursor counter : counters) {
if (counter.key.contains(".")) {
String[] parts = counter.key.split("\\.");
Map curr = map;
for (int i = 0; i < parts.length; i++) {
String part = parts[i];
boolean isLast = i == parts.length - 1;
if (isLast == false) {
if (curr.containsKey(part) == false) {
curr.put(part, new HashMap());
curr = (Map) curr.get(part);
} else {
curr = (Map) curr.get(part);
}
} else {
curr.put(part, counter.value);
}
}
} else {
map.put(counter.key, counter.value);
}
}
return map;
}
@Override
public void writeTo(StreamOutput out) throws IOException {
out.writeVInt(counters.size());
for (ObjectLongCursor cursor : counters) {
out.writeString(cursor.key);
out.writeVLong(cursor.value);
}
}
public static Counters merge(List counters) {
Counters result = new Counters();
for (Counters c : counters) {
for (ObjectLongCursor cursor : c.counters) {
result.inc(cursor.key, cursor.value);
}
}
return result;
}
}