Timer.java

package org.keycloak.testsuite.util;

import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 *
 * @author tkyjovsk
 */
public class Timer {

    private static Long time;

    private static final Map<String, List<Long>> stats = new HashMap<>();

    public static void time() {
        time = new Date().getTime();
    }

    public static void time(String operation) {
        if (time == null) {
            System.out.println(MessageFormat.format("Starting timer for operation {0}", operation));
            time();
        } else {
            long timeOrig = time;
            time();
            logOperation(operation, time - timeOrig);
            System.out.println(MessageFormat.format("Operation {0} took {1} ms", operation, time - timeOrig));
        }
    }

    private static void logOperation(String operation, long delta) {
        if (!stats.containsKey(operation)) {
            stats.put(operation, new ArrayList<Long>());
        }
        stats.get(operation).add(delta);
    }

    public static void printStats() {
        if (!stats.isEmpty()) {
            System.out.println("OPERATION STATS:");
        }
        for (String op : stats.keySet()) {
            long sum = 0;
            for (Long t : stats.get(op)) {
                sum += t;
            }
            System.out.println(MessageFormat.format("Operation {0} average time: {1,number,#} ms", op, sum / stats.get(op).size()));
        }
        stats.clear();
    }

}