Metric.java

/*
 * Copyright 2013 Proofpoint 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 org.kairosdb.client.builder;

import com.google.gson.annotations.SerializedName;

import java.util.*;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;

import static org.kairosdb.client.util.Preconditions.checkNotNullOrEmpty;

/**
 * A metric contains measurements or data points. Each data point has a time stamp of when the measurement occurred
 * and a value that is either a long or double and optionally contains tags. Tags are labels that can be added to better
 * identify the metric. For example, if the measurement was done on server1 then you might add a tag named "host"
 * with a value of "server1". Note that a metric must have at least one tag.
 */
public class Metric
{
	private String name;
	private Map<String, String> tags = new HashMap<String, String>();
	private String type;
	private int ttl;

	@SerializedName("datapoints")
	private List<DataPoint> dataPoints = new ArrayList<DataPoint>();

	protected Metric(String name)
	{
		this.name = checkNotNullOrEmpty(name);
	}

	protected Metric(String name, String registeredType)
	{
		this(name);
		type = registeredType;
	}

	/**
	 * Adds a tag to the data point.
	 *
	 * @param name  tag identifier
	 * @param value tag value
	 * @return the metric the tag was added to
	 */
	public Metric addTag(String name, String value)
	{
		checkNotNullOrEmpty(name);
		checkNotNullOrEmpty(value);
		tags.put(name, value);

		return this;
	}

	/**
	 * Adds tags to the data point.
	 * @param tags map of tags
	 * @return the metric the tags were added to
	 */
	public Metric addTags(Map<String, String> tags)
	{
		checkNotNull(tags);
		this.tags.putAll(tags);

		return this;
	}

	/**
	 * Adds the data point to the metric.
	 *
	 * @param timestamp when the measurement occurred
	 * @param value     the measurement value
	 * @return the metric
	 */
	public Metric addDataPoint(long timestamp, long value)
	{
		dataPoints.add(new DataPoint(timestamp, value));
		return this;
	}

	/**
	 * Adds the data point to the metric with a timestamp of now.
	 *
	 * @param value the measurement value
	 * @return the metric
	 */
	public Metric addDataPoint(long value)
	{
		return addDataPoint(System.currentTimeMillis(), value);
	}

	public Metric addDataPoint(long timestamp, Object value)
	{
		dataPoints.add(new DataPoint(timestamp, value));
		return this;
	}

	/**
	 * Adds the data point to the metric.
	 *
	 * @param timestamp when the measurement occurred
	 * @param value     the measurement value
	 * @return the metric
	 */
	public Metric addDataPoint(long timestamp, double value)
	{
		dataPoints.add(new DataPoint(timestamp, value));
		return this;
	}

	/**
	 * Adds the data point to the metric with a timestamp of now.
	 *
	 * @param value the measurement value
	 * @return the metric
	 */
	public Metric addDataPoint(double value)
	{
		return addDataPoint(System.currentTimeMillis(), value);
	}

	/**
	 * Adds a time-to-live for this metric specified in seconds. TTL is off by
	 * default. Setting ttl to 0 turns it off.
	 *
	 * @param ttl number of seconds that the metric will live
	 * @return the metric
	 */
	public Metric addTtl(int ttl)
	{
		checkArgument(ttl >= 0, "tll must be greater than or equal to zero");
		this.ttl = ttl;
		return this;
	}

	/**
	 * Returns the time-to-live. If zero, the metric lives forever.
	 * @return time to live
	 */
	public int getTtl()
	{
		return ttl;
	}

	public List<DataPoint> getDataPoints()
	{
		return Collections.unmodifiableList(dataPoints);
	}

	/**
	 * Returns the metric name.
	 *
	 * @return metric name
	 */
	public String getName()
	{
		return name;
	}

	/**
	 * Returns the tags associated with the data point.
	 *
	 * @return tag for the data point
	 */
	public Map<String, String> getTags()
	{
		return Collections.unmodifiableMap(tags);
	}

	/**
	 * Returns the custom type name. Null if the type is a number.
	 *
	 * @return custom type name
	 */
	public String getType()
	{
		return type;
	}

	@SuppressWarnings("SimplifiableIfStatement")
	@Override
	public boolean equals(Object o)
	{
		if (this == o)
			return true;
		if (o == null || getClass() != o.getClass())
			return false;

		Metric metric = (Metric) o;

		if (name != null ? !name.equals(metric.name) : metric.name != null)
			return false;
		if (tags != null ? !tags.equals(metric.tags) : metric.tags != null)
			return false;
		if (type != null ? !type.equals(metric.type) : metric.type != null)
			return false;
		return !(dataPoints != null ? !dataPoints.equals(metric.dataPoints) : metric.dataPoints != null);
	}

	@Override
	public int hashCode()
	{
		int result = name != null ? name.hashCode() : 0;
		result = 31 * result + (tags != null ? tags.hashCode() : 0);
		result = 31 * result + (type != null ? type.hashCode() : 0);
		result = 31 * result + (dataPoints != null ? dataPoints.hashCode() : 0);
		return result;
	}
}