Why does my program block while reading line from BufferedReader?

Question

I am executing some commands using ProcessBuilder as follows:

BufferedReader response = null;
process = processBuilder.start();           
response = new BufferedReader(new InputStreamReader(process.getInputStream()));

But code blocks at following line, while read line from response.

while((line = response.readLine()) != null) {
  /* some code here */
}

I did some google and I found that when readLine() not get EOL then it will block.

How can I make it work or resolve that issue.

one of the way around is that you can read bytes, while((i=bufferreader.read(buffer,i,100))!= -1) { //do work } — Addict, Mar 20 '13 at 20:46
Looks similar: http://stackoverflow.com/questions/6792835/how-do-you-set-a-timeout-on-bufferedreader-and-printwriter-in-java-1-4 — user1697575, Mar 20 '13 at 20:48

score 1 · Answer 1 · edited Mar 20 '13 at 20:53

1

According to the API, this is what is indicated for readLine()

Reads a line of text. A line is considered to be terminated by any one of a line feed ('\n'), a carriage return ('\r'), or a carriage return followed immediately by a linefeed.

So i think you'll have to make sure you are providing line terminator to avoid blocking.

edited Mar 20 '13 at 20:53

Hovercraft Full Of Eels

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answered Mar 20 '13 at 20:46

tmwanik

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How do I set line terminator? The response is returned by executing process builder. Just I can read it. right? – Sachin J Mar 20 '13 at 21:10
line = response.readLine() I dont get any response or string at this line. So I am unable to append '\n' at the end of line. – Sachin J Mar 20 '13 at 21:16
@Addict comment should sort that out, read `bytes` instead of `lines` – tmwanik Mar 20 '13 at 21:27

Why does my program block while reading line from BufferedReader?

1 Answers1