converting array of strings to ArrayList

Question

Possible Duplicate:
Assigning an array to an ArrayList in Java

How can I convert a array of strings like :

String logsSplitFromUrdu[] = fromTheRecentLogFile.split("غزل");

into a ArrayList<String> ?

Edit:

I was doing like when I get an error :

ArrayList<String> time = (ArrayList<String>)Arrays.asList(logsSplitFromUrdu);

EDIT :

Exception that I get when do the above :

java.lang.ClassCastException: java.util.Arrays$ArrayList cannot be cast to java.util.ArrayList
    at Tester.main(Tester.java:26)

Did you go through the documentation of : - [Array#asList](http://docs.oracle.com/javase/7/docs/api/java/util/Arrays.html#asList%28T...%29) — Rohit Jain, Oct 14 '12 at 14:52
Please copy/paste the new information into the question as an edit, and use code formatting on it. — Andrew Thompson, Oct 14 '12 at 14:55
asList returns a List not an ArrayList. 99.9% of the time, that does exactly the same thing. — Paul Tomblin, Oct 14 '12 at 15:01
http://stackoverflow.com/questions/4658867/why-does-arrays-aslist-return-its-own-arraylist-implementation — Natix, Oct 14 '12 at 15:16

score 2 · Accepted Answer · answered Oct 14 '12 at 14:51

Use the method Arrays.asList() from the Arrays class. It will return a List of the correct generic type (String in this case):

List<String> list = Arrays.asList(logsSplitFromUrdu);

If you absolutely need an ArrayList<String> and a List<String> won't do, then write one additional line after the previous one:

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

Rohit Jain · Answer 2 · 2012-10-14T15:17:28.077

2

Take a look at Arrays#asList. This method returns a fixed size list.

So, if you are ok with fixed size list, then you can use this: -

List<String> fixedList = Arrays.asList(logsSplitFromUrdu);

But, if you want to modify your newly created List, you need to create it like this: -

ArrayList<String> modifiableList = 
             new ArrayList<String>(Arrays.asList(logsSplitFromUrdu))

BUT you should not do it like this: -

ArrayList<String> modifiableList = 
                  (ArrayList<String>)Arrays.asList(logsSplitFromUrdu))

It will give you ClassCastException, because, the list returned from Arrays.asList is of type: - java.util.Arrays.ArrayList and it cannot be cast to : - java.util.ArrayList

UPDATE: - java.util.Arrays#ArrayList is a static class defined in Arrays class.

edited Oct 14 '12 at 15:17

answered Oct 14 '12 at 14:54

Rohit Jain

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`java.util.List.ArrayList` I doubt if it even exists ! – Y.E.P Oct 14 '12 at 15:09
@Y.E.P Sorry its. java.util.Arrays.ArrayList. Will modify it.. – Rohit Jain Oct 14 '12 at 15:11
@Y.E.P See this excellent Post: - http://stackoverflow.com/questions/4658867/why-does-arrays-aslist-return-its-own-arraylist-implementation for more information about this – Rohit Jain Oct 14 '12 at 15:14

Reimeus · Answer 3 · 2012-10-14T15:22:00.357

0

The return type of

Arrays.asList(logsSplitFromUrdu);

is List<String> and cannot be cast to ArrayList<String>. Instead you can use:

List<String> myList = Arrays.asList(logsSplitFromUrdu);

which returns an unmodifiable list. To get a modifiable list you could use:

ArrayList<String> modifyiableList = new ArrayList<String>(myList); 
modifyiableList.add("...");

edited Oct 14 '12 at 15:22

answered Oct 14 '12 at 14:52

Reimeus

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score 0 · Answer 4 · answered Oct 14 '12 at 14:52

0

U have to use asList method of java.util.Arrays, refer the docs here

answered Oct 14 '12 at 14:52

Akhilesh

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score 0 · Answer 5 · answered Oct 14 '12 at 14:55

0

Use the Arrays.asList() method to convert the array into ArrayList

String logsSplitFromUrdu[] = fromTheRecentLogFile.split("غزل");

ArrayList<String> arList = new ArrayList<String>(Array.asList(logsSplitFromUrdu));

answered Oct 14 '12 at 14:55

Kumar Vivek Mitra

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score 0 · Answer 6 · answered Oct 14 '12 at 15:19

You can simply use a for loop to copy all of the elements from the array into a new ArrayList like so:

ArrayList<String> logsList = new ArrayList<String>();
for(int i = 0; i < logsSplitFromUrdu.length; i++)
{
    logsList.add(logsSplitFromUrdu[i]);
}

And after this logsList will contain all of the elements in your original array.

converting array of strings to ArrayList

6 Answers6