Reading an inputStream all at once

Question

I have developed a j2me application that connects to my webhosting server through sockets. I read responses from the server using my own extended lineReader class that extends the basic InputStreamReader. If the server sends 5 lines of replies, the syntax to read the server replies line by line is:

        line=input.readLine();
        line = line + "\n" + input.readLine();
        line = line + "\n" + input.readLine();
        line = line + "\n" + input.readLine();
        line = line + "\n" + input.readLine();

In this case, i can write this syntax because i know that there is a fixed number of replies. But if I dont know the number of lines, and want to read the whole inputStream at once, how should I modify the current readLine() function. Here's the code for the function:

public String readLine() throws IOException {
    StringBuffer sb = new StringBuffer();
    int c;
    while ((c = read()) > 0 && c != '\n' && c != '\r' && c != -1) {
        sb.append((char)c);
    }
    //By now, buf is empty.
    if (c == '\r') {
        //Dos, or Mac line ending?
        c = super.read();
        if (c != '\n' && c != -1) {
            //Push it back into the 'buffer'
            buf = (char) c;
            readAhead = true;
        }
    }
    return sb.toString();
}

Andrew White · Accepted Answer · 2011-04-22T01:47:13.823

10

What about Apache Commons IOUtils.readLines()?

Get the contents of an InputStream as a list of Strings, one entry per line, using the default character encoding of the platform.

Or if you just want a single string use IOUtiles.toString().

Get the contents of an InputStream as a String using the default character encoding of the platform.

[update] Per the comment about this being avaible on J2ME, I admit I missed that condition however, the IOUtils source is pretty light on dependencies, so perhaps the code could be used directly.

edited Apr 22 '11 at 01:47

answered Apr 22 '11 at 01:41

Andrew White

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but is it available for the j2me platform? – Sujit Agarwal Apr 22 '11 at 01:43
@Coding-Freak: sorry I missed that; I am somewhat ignorant about the J2ME platform so I updated my answer with the best I know of, good luck. – Andrew White Apr 22 '11 at 01:46
I just want to modify my currently working `readLine()` function to be able to read the whole stream all at once. Hope you understand the question. – Sujit Agarwal Apr 22 '11 at 01:52

Vikrant Goel · Answer 2 · 2013-10-23T05:30:49.323

1

Specifically for web server !

String temp;
StringBuffer sb = new StringBuffer();
while (!(temp = input.readLine()).equals("")){
    sb.append(line);
}

edited Oct 23 '13 at 05:30

answered Jan 26 '13 at 23:49

Vikrant Goel

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score 1 · Answer 3 · answered Apr 22 '11 at 02:06

1

If I understand you correctly, You can use a simple loop:

StringBuffer sb = new StringBuffer();
String s;
while ((s = input.readLine()) != null)
    sb.append(s);

Add a counter in your loop, and if your counter = 0, return null:

int counter = 0;
while ((c = read()) > 0 && c != '\n' && c != '\r' && c != -1) {
    sb.append((char)c);
    counter++;
}
if (counter == 0)
    return null;

answered Apr 22 '11 at 02:06

MByD

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i modified the code as you said. now its returning no response from the server. – Sujit Agarwal Apr 22 '11 at 02:12
This is not an entire example. you should add some EOF flag if -1 has received and not read after that. – MByD Apr 22 '11 at 02:17
please help me with the rest code. i am totally stuck with it. :( – Sujit Agarwal Apr 22 '11 at 02:24
I can't write a real and tested code right now anyhow (since I don't have java environment on this computer) but why don't you use the while loop I suggested (at the beginning of my answer) with the original readLine, not your extension? – MByD Apr 22 '11 at 02:27

Reading an inputStream all at once

3 Answers3