Change array list to list of lists java

Question

I have two lists and I want to make a list of lists. For some reason after I print out each list, I get a massive one entry in the array. I am using the data coming from a hash map, and need to split the key string to get the values back, then cast the integer to a string to add to array.

    ArrayList<ArrayList<String>> listOLists = new ArrayList<ArrayList<String>>();
    ArrayList<String> singleList = new ArrayList<String>();
        for (Entry<String, Integer> entry : counts.entrySet()) {
              String val = entry.getValue().toString();               
              List<String> key = Arrays.asList(entry.getKey().split("@"));
              singleList.add(key.get(0));
              singleList.add(key.get(1));
              singleList.add(key.get(2));
              singleList.add(val);
              listOLists.add(singleList);
        }


        for(ArrayList<String> s: listOLists){
            System.out.println(s);
        }

I am getting:

[Demo-Site, 172.20.58.160, 2015-08-06, 12, Demo-Site, 10.227.145.103, 2015-08-19, 1, Demo-Site, 10.7.0.146, 2015-08-11, 3,

I want in the final output to look something like this:

[[Demo-site, 172.20.58.160, 2015-08-06, 12], [Demo-site, 10.227.145.103, 2015-08-19, 1]..etc]

Show what you are getting and how you are printing

Suresh Atta
– Suresh Atta

2015-08-25 16:09:26 +00:00
Commented Aug 25, 2015 at 16:09 — Suresh Atta
– Suresh Atta, Commented Aug 25, 2015 at 16:09
@sᴜʀᴇsʜᴀᴛᴛᴀ updated post.

Ben
– Ben

2015-08-25 16:24:54 +00:00
Commented Aug 25, 2015 at 16:24 — Ben
– Ben, Commented Aug 25, 2015 at 16:24

Maxwellt · Accepted Answer · 2015-08-25 16:26:14Z

2

It's because you add in the same single list in every iteration. Just put singleList = new ArrayList(); in tle loop body.

answered Aug 25, 2015 at 16:26

Maxwellt

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Comments

shiva upadhyay · Accepted Answer · 2015-08-25 16:25:23Z

1

Have the last println as sopln ("[" + s + "]"); something like this should give you the output that you want.

answered Aug 25, 2015 at 16:25

shiva upadhyay

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