Question

I have a very strange memory problem with my Android app.
My app use 3 classes that are the following:

public class RGB 
{
    public int R;
    public int G;
    public int B;
}

public class CMYK 
{
    public int C;
    public int M;
    public int Y;
    public int K;
}

public class COLOR 
{
    public String id;
    public CMYK cmyk = new CMYK();
    public RGB rgb = new RGB();

    public COLOR(String id, int c, int m, int y, int k, int r, int g, int b)
    {
        this.id = id;

        this.cmyk.C = c;
        this.cmyk.M = m;
        this.cmyk.Y = y;
        this.cmyk.K = k;

        this.rgb.R = r;
        this.rgb.G = g;
        this.rgb.B = b;
    }
}

then somewere in the code I have to load 2000 colors from a file (file is about 65K lenght and has exactly 2000 records) and is placed in assets folder

public COLOR[] color_list = new COLOR[2000];
...
...
do
{
    s = reader.readLine();
    if (s != null)
    {
        String[] x = s.split(" ");
        COLOR c = new COLOR(x[0], Integer.parseInt(x[1]), Integer.parseInt(x[2]), Integer.parseInt(x[3]), Integer.parseInt(x[4]), Integer.parseInt(x[5]), Integer.parseInt(x[6]), Integer.parseInt(x[7]));
        color_list[j++] = c;
    }

} while (s != null);

after this the app will crash and stop working. If I remove the do..while all is working, so I think my array will be more and more and more then 65K, what I have done wrong? On Android LogCat I have reached the full of HEAP space (26MB) !!!

Best regards
GMG

Answer 1

I don’t think that code is responsible of the OutOfMemoryException. Maybe there are other fields you don’t mention, but without running the code one can’t tell.

However there may be a small leak when you create the ID. Whenever you create a String from an existing one (either substring()-based or methods in the regex package), the returned string keeps an internal reference to the old one: it’s just a thin wrapper around the old sequence of characters, just with different start and different length. This means that you’d better create your ID like this

String id = new String(x[0]);

This way you don’t keep the whole line in memory just to store a few characters.

However, this is an optimization, since you state that your file is 65KB, so even if you retain it all in-memory, it wouldn’t crash your application. Post the whole code so we can run and analyze it.

BTW, you can save an indentation level this way:

String line;
Pattern pattern = Pattern.compile(" "); // Help the GC ;)

while ((line = in.readLine()) != null) {
    String[] data = pattern.split(line);

    // Ugly, but still better than a 8-args constructor
    RGB rgb = new RGB(data, 1, 3);
    CMYK cmyk = new CMYK(data, 4, 4);

    // the best would be a constructor like Color(String[8])
    colors[j++] = new Color(new String(data[0]), rgb, cmyk);
}

I also changed the API a bit (I found this more comfortable)