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A library usefull for unit testing memory leaks

There is a newer version: 0.5.5

package de.sandec.jmemorybuddy;

import com.sun.management.HotSpotDiagnosticMXBean;
import javax.management.MBeanServer;
import java.io.IOException;
import java.lang.management.ManagementFactory;
import java.lang.ref.WeakReference;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.LinkedList;
import java.util.function.Consumer;
import java.util.function.Function;

public class MemoryLeakUtils {

    static int steps = 10;
    static int overallTime = 5000;
    static int sleepTime = overallTime / steps;

    public static void createGarbage() {
        LinkedList list = new LinkedList();
        int counter = 0;
        while(counter < 999999) {
            counter += 1;
            list.add(1);
        }
    }

    public static void assertCollectable(WeakReference weakReference) {
        int counter = 0;

        createGarbage();
        System.gc();

        while(counter < steps && weakReference.get() != null) {
            try {
                Thread.sleep(sleepTime);
            } catch (InterruptedException e) {}
            counter = counter + 1;
            createGarbage();
            System.gc();
        }

        if(weakReference.get() != null) {
            doHeapDump();
            throw new RuntimeException("Content of Weakreference was not collected. content: " + weakReference.get());
        } else {
            if(counter > steps / 3) {
                int percentageUsed = (int) (counter / steps * 100);
                System.out.println("Warning test seems to be unstable. time used: " + percentageUsed + "%");
            }
        }

    }

    public static void doMemTest(Consumer> f) {
        LinkedList> toCheck = new LinkedList>();

        f.accept((Object elem) -> toCheck.add(new WeakReference