Improve company productivity with a Business Account.Sign Up

x
?
Solved

Element in arraylist of arraylists

Posted on 2013-11-19
2
Medium Priority
?
298 Views
Last Modified: 2013-11-19
Working in Java, how do I address a specific item in an array list of arraylists?

I have the constructor:
ArrayList<ArrayList<Integer>> testpaths = new ArrayList<ArrayList<Integer>>();

Which when I print to console:
System.out.println(testpaths + "\n");

Output after running some method() is:
[[], [1], [2], [1, 5, 3], [2, 4], [1, 5], [1, 5, 6], [1, 5, 7]]

Let's say that in that 8th item [1,5,7] - I just want the "1".

Thanks!
0
Comment
Question by:Geisrud
  • 2
2 Comments
 
LVL 14

Accepted Solution

by:
jb1dev earned 2000 total points
ID: 39661102
testpaths.get(7).get(0);
0
 
LVL 14

Expert Comment

by:jb1dev
ID: 39661112
The above should work fine provided you have the generics in place, as you do in your example. If you did not have the generics in place, you would need to cast the first get() result back as an ArrayList.

E.g.
((ArrayList)testpaths.get(7)).get(0);
0

Featured Post

What Kind of Coding Program is Right for You?

There are many ways to learn to code these days. From coding bootcamps like Flatiron School to online courses to totally free beginner resources. The best way to learn to code depends on many factors, but the most important one is you. See what course is best for you.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Introduction This article is the second of three articles that explain why and how the Experts Exchange QA Team does test automation for our web site. This article covers the basic installation and configuration of the test automation tools used by…
In this post we will learn how to make Android Gesture Tutorial and give different functionality whenever a user Touch or Scroll android screen.
This tutorial will introduce the viewer to VisualVM for the Java platform application. This video explains an example program and covers the Overview, Monitor, and Heap Dump tabs.
How to fix incompatible JVM issue while installing Eclipse While installing Eclipse in windows, got one error like above and unable to proceed with the installation. This video describes how to successfully install Eclipse. How to solve incompa…

595 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question