top button
Flag Notify
    Connect to us
      Facebook Login
      Site Registration

Facebook Login
Site Registration

Which collection classes provide random access of it’s elements?

+1 vote
76 views
Which collection classes provide random access of it’s elements?
posted Dec 20, 2017 by Jon Deck

Share this question
Facebook Share Button Twitter Share Button LinkedIn Share Button

1 Answer

0 votes

RandomAccess interface is a marker interface used by List implementations to indicate that they support fast (generally constant time) random access. Primary purpose of this interface was to allow generic algorithms to alter their behavior and provide good performance when applied to either random or sequential access lists.

All Known Implementing Classes:

ArrayList, AttributeList, CopyOnWriteArrayList, RoleList, RoleUnresolvedList, Stack, Vector

Also it is known that distinction between random and sequential access is often uncertain. For example : some of the List implementations provide random access times if they get huge, but constant access times in general practice. Let’s see example below:

package com.javahonk.randomaccess;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

public class RamdomAccessTest {

    public static void main(String args[]) {

    List<String> list = new ArrayList<String>();

    for (int i = 0; i < 50000; i++) {
        list.add("Java");
        list.add("Honk");
    }

    Long startTime = System.currentTimeMillis();
    System.out.println("Start time: " + startTime);

    for (int i = 0, n = list.size(); i < n; i++) {
        list.get(i);
    }

    Long time1 = System.currentTimeMillis();
    System.out.println("Example 1 time in milli: " + (time1 - startTime));

    for (Iterator<String> i = list.iterator(); i.hasNext();) {
        i.next();
    }

    Long time2 = System.currentTimeMillis();
    System.out.println("Example 2 time in milli: " + (time2 - time1));

    for (String string : list) {

    }

    Long time3 = System.currentTimeMillis();
    System.out.println("Example 3 time in milli: " + (time3 - time2));

    if (time2 > time1) {
        System.out.println("Example 1 is faster");
    } else if (time3 > time2) {
        System.out.println("Example 2 is faster");
    } else {
        System.out.println("Example 3 is faster");
    }

    }

}

Output:

Start time: 1395082451059
Example 1 time in milli: 2
Example 2 time in milli: 6
Example 3 time in milli: 4
Example 1 is faster
answer Dec 27, 2017 by Manikandan J
Similar Questions
+1 vote

If my understanding is correct then as part of handover procedure, UE can do either contention based rach or non-contention based.
Now my question is that on what parameter basis target eNodeB decide for an UE to do contention/non-contention based rach during the handover procedure ?

Contact Us
+91 9880187415
sales@queryhome.net
support@queryhome.net
#280, 3rd floor, 5th Main
6th Sector, HSR Layout
Bangalore-560102
Karnataka INDIA.
QUERY HOME
...