php ssh2_exec not executing java command

Question

Below code is not able to get the Java version using ssh2_exec, I have tried absolute path /usr/bin/java as well, same code is working with 'php --version', what could the possible reason for this issue?

Already done chmod 777 for /usr/bin/java

  $connection = ssh2_connect('xx.xx.xx.xx', 22);
  ssh2_auth_password($connection, $username, $password);

  $stream = ssh2_exec($connection, 'java -version;');
  stream_set_blocking($stream, true);
  $tempVar = stream_get_contents($stream);

  echo $tempVar; // nothing printed here 

Answer 1

One issue could be the semi-colon on the command you are executing.

$stdout_stream = ssh2_exec($connection, "java -version");

$err_stream = ssh2_fetch_stream($stdout_stream, SSH2_STREAM_STDERR);

$dio_stream = ssh2_fetch_stream($stdout_stream, SSH2_STREAM_STDDIO);

stream_set_blocking($err_stream, true);
stream_set_blocking($dio_stream, true);

$result_err = stream_get_contents($err_stream));
$result_dio = stream_get_contents($dio_stream));

Check the stderr stream to see if it returns an error.