com.google.enterprise.adaptor.prebuilt

Class StreamingCommand

java.lang.Object

com.google.enterprise.adaptor.prebuilt.StreamingCommand

public class StreamingCommand
extends Object

Exec helper that allows easy handling of stdin, stdout, and stderr. Normally you have to worry about deadlock when dealing with those streams (as mentioned briefly in Process), so this class handles that for you. This class is very similar to Command, except it allows streaming stdin, stdout, and stderr, instead of buffering them.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	StreamingCommand.InputSource Content source that generates content at the rate it can be consumed.
static interface	StreamingCommand.OutputSink Content sink that consumes content as soon as it becomes available.

Method Summary

Modifier and Type	Method and Description
static int	exec(String[] command, File workingDir, StreamingCommand.InputSource stdin, StreamingCommand.OutputSink stdout, StreamingCommand.OutputSink stderr) Create process command starting in the workingDir and providing stdin as input.
static int	exec(String[] command, StreamingCommand.InputSource stdin, StreamingCommand.OutputSink stdout, StreamingCommand.OutputSink stderr) Same as exec(command, null, stdin, stdout, stderr).
static StreamingCommand.InputSource	streamInputSource(InputStream in) InputStream to StreamingCommand.InputSource adaptor.
static StreamingCommand.OutputSink	streamOutputSink(OutputStream out) OutputStream to StreamingCommand.OutputSink adaptor.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

exec

public static int exec(String[] command,
                       StreamingCommand.InputSource stdin,
                       StreamingCommand.OutputSink stdout,
                       StreamingCommand.OutputSink stderr)
                throws IOException,
                       InterruptedException

Same as exec(command, null, stdin, stdout, stderr).

Parameters:

command - command

stdin - stdin

stdout - stdout

stderr - stderr

Returns:

Process return code

Throws:

IOException - if creating process fails

InterruptedException - if interrupted

See Also:

exec(String[], File, InputSource, OutputSink, OutputSink)

exec

public static int exec(String[] command,
                       File workingDir,
                       StreamingCommand.InputSource stdin,
                       StreamingCommand.OutputSink stdout,
                       StreamingCommand.OutputSink stderr)
                throws IOException,
                       InterruptedException

Create process command starting in the workingDir and providing stdin as input. This method blocks until the process exits. Stdout and stderr must be consumed via the StreamingCommand.OutputSinks. If stdin, stdout, or stderr is null, then a bare implemention will be used.

Parameters:

command - command

workingDir - workingDir

stdin - stdin

stdout - stdout

stderr - stderr

Returns:

Process return code

Throws:

IOException - if creating process fails

InterruptedException - if interrupted

streamInputSource

public static StreamingCommand.InputSource streamInputSource(InputStream in)

InputStream to StreamingCommand.InputSource adaptor.

Parameters:

in - input stream

Returns:

input source

streamOutputSink

public static StreamingCommand.OutputSink streamOutputSink(OutputStream out)

OutputStream to StreamingCommand.OutputSink adaptor.

Parameters:

out - output stream

Returns:

output sink