Can anyone clarify me if the below procedure is correct way to handle streams of process without any stream buffer full and blocking problems
I'm invoking external program from java program, I'm using ProcessBuilder to build the process and after I perform
Process gpgProcess = processBuilder.start();
I'm handling the process using a method
String executionResult = verifyExecution(gpgProcess);
and in my method i'm trying to handle the process streams
private String verifyExecution(Process gpgProcess) throws IOException, InterruptedException {
String gpgResult = null;
BufferedReader stdOut = new BufferedReader(new InputStreamReader(gpgProcess.getInputStream()));
BufferedReader stdErr = new BufferedReader(new InputStreamReader(gpgProcess.getErrorStream()));
gpgProcess.waitFor();
if(stdErr.ready()) {
gpgResult = "Exit code: " + gpgProcess.exitValue() + "
" + readStream(stdErr);
} else if(stdOut.ready()) {
gpgResult = "Exit code: " + gpgProcess.exitValue() + "
" + readStream(stdOut);
} else {
gpgResult = "Exit code: " + gpgProcess.exitValue();
}
int exitCode = gpgProcess.exitValue();
this.setExitCode(exitCode);
stdOut.close();
stdErr.close();
if(exitCode != 0) {
throw new RuntimeException("Pgp Exception: " + gpgResult);
}
return gpgResult;
}
The readStream method is used to read my stream text.
private String readStream(BufferedReader reader) throws IOException {
StringBuilder result = new StringBuilder();
try {
while(reader.ready()) {
result.append(reader.readLine());
if(reader.ready()) {
result.append("
");
}
}
} catch(IOException ioe) {
System.err.println("Error while reading the stream: " + ioe.getMessage());
throw ioe;
}
return result.toString();
}
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