Array Not Resizing

Question

I'm trying to resize an Array[] using a method named resize(). I think I've coded the method correctly, however the original array does not resize after running it through the method, and I'm not sure what I'm doing wrong.

I've tested that the newArr[] is in fact twice the length of the oldArr[] and contained the values of the oldArr[], but I can't figure out why it's not taking affect to the wordList[] in the main method.

My assignment is to use Arrays and not Arraylists, so using that is out of the question.

infile = new BufferedReader( new FileReader(infileName) );
while (infile.ready()) {

    String s = infile.readLine();
    System.out.println(wordList.length);
    System.out.println(count);
    wordList[count] = s;

    if(s.length() > lenOfLongest)
        lenOfLongest = s.length();

    if(s.length() < lenOfShortest)
        lenOfShortest = s.length();

    count++;

    if(count == wordList.length)
            resize(wordList);
}

private static String[] resize( String[] oldArr ) {
    String[] newArr = new String[oldArr.length * 2];
    System.out.println(newArr.length);

    for(int i = 0;i < oldArr.length; i++) {
        newArr[i] = oldArr[i];
    }

    return newArr;

}

See Fouads answer, your method returns something that is thrown away immediately, you need to point your wordlist to the return value. — arynaq, May 31 '13 at 18:48

score 4 · Answer 1 · edited May 23 '17 at 12:18

4

if(count == wordList.length)
        resize(wordList);

should be:

if(count == wordList.length)
        wordList = resize(wordList);

See this answer for more details.

edited May 23 '17 at 12:18

Community

1
1

answered May 31 '13 at 18:47

Eng.Fouad

115,165
71
313
417

score 1 · Answer 2 · answered May 31 '13 at 18:48

1

As @pad says in his comment: you don't reassing to wordList.

And your resize() method returns a new array. You should therefore reassing wordList.

As a general note, arrays are not resizable in Java.

answered May 31 '13 at 18:48

fge

119,121
33
254
329

score 0 · Answer 3 · answered May 31 '13 at 18:47

0

Because you are not assign the returned array to anything.Must be as follows.

String[] temp = resize(wordList);

answered May 31 '13 at 18:47

Salih Erikci

5,076
12
39
69

Array Not Resizing

3 Answers3