adding two arraylists into one

Question

I want to check branchList whether has same element or not, if same put branchList and tglList element separate arraylist and put that arraylist into another arraylist,

The result I want is BranchList1 have 2 arraylist where 1st arraylist contain for element '1' and 2nd arraylist contain element '2' and TglList1 have 2 arraylist as element, but what i get is both 1st and 2nd array get same value.

How can this be done?

ArrayList branchList = new ArrayList();
    branchList.add("1");
    branchList.add("1");
    branchList.add("1");
    branchList.add("2");
    branchList.add("2");
    branchList.add("2");

    ArrayList tglList = new ArrayList();
    tglList.add("5");
    tglList.add("10");
    tglList.add("20");
    tglList.add("100");
    tglList.add("500");
    tglList.add("1000");


    ArrayList newBranchList = new ArrayList();
    ArrayList newTglList = new ArrayList();

    ArrayList BranchList1 = new ArrayList();
    ArrayList TglList1 = new ArrayList();


    ArrayList abc = new ArrayList();
    String checkBranch = new String();

    for(int i=0;i<branchList.size();i++){
        String branch = branchList.get(i).toString();
        if(i==0 || checkBranch.equals(branch)){
            newBranchList.add(branch);
            newTglList.add(tglList.get(i).toString());
        }else{
            BranchList1.add(newBranchList);
            TglList1.add(newTglList);

            newBranchList.clear();
            newTglList.clear();

            newBranchList.add(branch);
            newTglList.add(tglList.get(i).toString());
        }
        if(i==(branchList.size()-1)){
            BranchList1.add(newBranchList);
            TglList1.add(newTglList);
        }
        checkBranch = branch;
    }

}

so expected result is as below:

BranchList1 = [ [1,1,1],[2,2,2]]
TglList1 = [[5,10,20],[50,100,200]]

but what I get is

BranchList1 = [ [2,2,2],[2,2,2]]
TglList1 = [[50,100,200],[50,100,200]]

How can I modify the code

Answer 1

I didn't thoroughly read through your code (and I don't quite get what you're asking for), but if you want to merge (add the elements of) branchList and tglList to TglList1, try this:

TglList1.addAll(branchList);
TglList1.addAll(tglList);

After that, TglList1 should contain all elements of both lists. If you need the list to be sorted, you might want to call Collections.sort(TglList1) afterwards (just note that sorting strings might place "100" before "2", due to "1" being lexically smaller than "2").