sirius.kernel.health.metrics.Metric Maven / Gradle / Ivy

Go to download
/*
 * Made with all the love in the world
 * by scireum in Remshalden, Germany
 *
 * Copyright by scireum GmbH
 * http://www.scireum.de - [email protected]
 */

package sirius.kernel.health.metrics;

import sirius.kernel.commons.Amount;
import sirius.kernel.commons.Explain;
import sirius.kernel.commons.NumberFormat;

import java.util.Objects;

/**
 * Represents a measured value, recorded by the metrics framework.
 * 
 * Basically this combines a name along with a value and unit. Additionally an interpretation of the value is
 * given as state.
 */
public class Metric implements Comparable {

    private String code;
    private final String unit;
    private String label;
    private double value;
    private MetricState state;

    /**
     * Creates a new metric using the given values
     *
     * @param code  the unique technical name of the metric
     * @param label the name of the metric
     * @param value the actual value
     * @param state the interpretation of the value
     * @param unit  the unit in which the value is measured or null if there is no unit
     */
    public Metric(String code, String label, double value, MetricState state, String unit) {
        this.code = code;
        this.unit = unit;
        this.label = label;
        this.value = Double.isNaN(value) ? 0 : value;
        this.state = state;
    }

    /**
     * Returns the unique code of the metric.
     * @return the ocde of this metric.
     */
    public String getCode() {
        return code;
    }

    /**
     * Returns the label of the metric.
     *
     * @return the label of the metric
     */
    public String getLabel() {
        return label;
    }

    /**
     * Returns the actual value of the metric.
     *
     * @return the measured value of the metric
     */
    public double getValue() {
        return value;
    }

    /**
     * The unit in which the value is measured
     *
     * @return the unit of the value or null if there is no unit
     */
    public String getUnit() {
        return unit;
    }

    /**
     * String representation of the value along with its unit (is necessary)
     *
     * @return a string representation of the value
     */
    public String getValueAsString() {
        return Amount.of(value).toSmartRoundedString(NumberFormat.TWO_DECIMAL_PLACES).append(" ", unit).toString();
    }

    /**
     * Returns an interpretation of the value (@see MetricState).
     *
     * @return an interpretation of the value
     */
    public MetricState getState() {
        return state;
    }

    @Override
    @SuppressWarnings("squid:S1698")
    @Explain("Indentity against this is safe and a shortcut to speed up comparisons")
    public int compareTo(Metric o) {
        if (o == null) {
            return -1;
        }
        if (o == this) {
            return 0;
        }
        if (o.state != state) {
            return o.state.ordinal() - state.ordinal();
        }
        return code.compareTo(o.code);
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (!(o instanceof Metric)) {
            return false;
        }
        Metric metric = (Metric) o;
        return Objects.equals(code, metric.code) && state == metric.state;
    }

    @Override
    public int hashCode() {
        return Objects.hash(code, state);
    }
}