How to choose the buffer size when reading from a URL

Question

Aim : To read a Url which containing information in Json.

Question: I got a code of reading Url Which is given Below. I have a complete Understanding what code is doing but I do not have any idea why the size of char array is 1024 not 2048 or something else . How to decide what character size array is good at the time of reading Url ?

private static String readUrl(String urlString) throws Exception {
    BufferedReader reader = null;
    try {
        URL url = new URL(urlString);
        reader = new BufferedReader(new InputStreamReader(url.openStream()));
        StringBuffer buffer = new StringBuffer();
        int read;
        char[] chars = new char[1024]; ???   

        while ((read = reader.read(chars)) != -1)
            buffer.append(chars, 0, read); 

        return buffer.toString();
    } finally {
        if (reader != null)
            reader.close();
    }
}

There is no reason this is 1024 but it cant be 2048 usually, read this http://stackoverflow.com/questions/417142/what-is-the-maximum-length-of-a-url-in-different-browsers — Lrrr, Dec 09 '14 at 07:26
@AliAmiri This question is not about the length of the URL string. It is about reading the content. The shown code uses the `char[]` in a loop for reading that content. — Seelenvirtuose, Dec 09 '14 at 07:56
@Seelenvirtuose how much it reads is depend on how long URL is. — Lrrr, Dec 09 '14 at 08:02
yes @Seelenvirtuose I am talking about the length of char array. Is there any any document or anything by which I can correct my doubt about it. — mystertyboy, Dec 09 '14 at 08:16
@AliAmiri provided link is useful thanks for it. by reading that i can create a thumb rule not to use char array more than 1024 because browsers url read is something around <2048 .Is it the only reason of using 1024 or less than 2048 ? if I use 512 so its performance will increase or decrease ? I think decrease now program will run reading url twice. am I Right ? — mystertyboy, Dec 09 '14 at 08:22

score 0 · Answer 1 · answered Dec 09 '14 at 08:37

As the BufferedReader already has an internal buffer of 4096 characters, implementation-dependent, and as the socket already has a considerably larger receive buffer, it really doesn't make much difference what value you choose. The returns on buffering diminish geometrically with size.

How to choose the buffer size when reading from a URL

1 Answers1