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Just some useful utils for everyday coding

There is a newer version: 1.2

package com.github.simonharmonicminor.juu.measure;

import com.github.simonharmonicminor.juu.lambda.Action;

import java.util.Objects;
import java.util.function.Supplier;

/**
 * A class for measuring time of function execution with retrieving result.
 *
 * @param  type of function return result
 * @see ExecutionResult
 * @since 0.1
 */
public class Measure {

    private final Supplier supplier;

    private Measure(Supplier supplier) {
        this.supplier = supplier;
    }

    /**
     * Creates an instance of {@link Measure} class with function that will be executed Function will
     * not be executed until {@link Measure#inMillis()} or {@link Measure#inNanos()} will be called
     *
     * @param supplier lambda function which needs to be executed. Cannot be null
     * @param       function return type
     * @return an instance of class with given function
     * @throws NullPointerException if supplier is null
     */
    public static  Measure executionTime(Supplier supplier) {
        Objects.requireNonNull(supplier);
        return new Measure<>(supplier);
    }

    /**
     * Creates an instance of {@link Measure} class with procedure that will be executed. Procedure
     * will not be executed until {@link Measure#inMillis()} or {@link Measure#inNanos()} will be
     * called
     *
     * @param action lambda procedure which needs to be executed. Cannot be {@code null}
     * @return an instance of class with given procedure
     * @throws NullPointerException if action is null
     */
    public static Measure executionTime(Action action) {
        Objects.requireNonNull(action);
        return new Measure<>(
                () -> {
                    action.execute();
                    return null;
                });
    }

    /**
     * @return execution result measured in millis.
     */
    public ExecutionResult inMillis() {
        long time = System.currentTimeMillis();
        T result = supplier.get();
        return new ExecutionResult<>(result, System.currentTimeMillis() - time, MeasureUnit.MILLIS);
    }

    /**
     * @return execution result measured in nanos.
     */
    public ExecutionResult inNanos() {
        long time = System.nanoTime();
        T result = supplier.get();
        return new ExecutionResult<>(result, System.nanoTime() - time, MeasureUnit.NANOS);
    }
}