magpie.models.utility

Class ExternalModelUtility

java.lang.Object

magpie.models.utility.ExternalModelUtility

public class ExternalModelUtility
extends java.lang.Object

Utility operation for models that rely on an external (i.e., non-java) process and use a socket connection to exchage information.

Assumes that...

1. The process reads the model state from standard in
2. For each connection, the server takes the command for what to do as a plaintext word in the first line. Commands can be:
   • "train" - Which is followed by the number of entries, and a line for each entry where the first number is the class variable the remaining numbers are the attributes. Once training is complete, the server responds with the model state as a data stream.
   • "run" - Which is followed by the number of entries, and a line for each entry with the attributes printed out. The server responds with the same number of lines of output, which contain either probabilities of membership in each class [classification] or predicted class [regression]
   • "type" - Followed by no other data. The server responds with a description of model as plain text.
   • "exit" - Stop the server

Constructor Summary

Constructors

Constructor and Description
ExternalModelUtility()

Method Summary

Modifier and Type	Method and Description
static java.util.List<java.lang.String>	getModelDescription(ExternalModel model) Generate a description of the model
static int	initializeServer(ExternalModel model, boolean debug) Assuming that a model server is already launched, get the port number and send the model object stream to the standard input of the server process.
static boolean	isRunning(java.lang.Process process) Check whether a process is running
static void	runModel(ExternalModel model, Dataset runData) Connect to server and run model
static void	startReader(java.io.InputStream processStream, java.io.OutputStream outputStream) Launch a thread that does nothing but read from the output of another process.
static void	stopServer(ExternalModel model) Send the "exit" command and stop a server
static void	trainModel(ExternalModel model, Dataset trainData) Make a call to the model server to train a model

Methods inherited from class java.lang.Object

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

Constructor Detail

ExternalModelUtility

public ExternalModelUtility()

Method Detail

startReader

public static void startReader(java.io.InputStream processStream,
                               java.io.OutputStream outputStream)

Launch a thread that does nothing but read from the output of another process.

Optionally, it can also write this data to another stream

Parameters:

processStream - Stream to be read from

outputStream - Stream to be written to. Put "null" for no output

isRunning

public static boolean isRunning(java.lang.Process process)

Check whether a process is running

Parameters:

process - Process

Returns:

Whether it is running

initializeServer

public static int initializeServer(ExternalModel model,
                                   boolean debug)
                            throws java.lang.Exception

Assuming that a model server is already launched, get the port number and send the model object stream to the standard input of the server process.

Parameters:

model - Model being operated on

debug - Whether to print standard out, or ignore it

Returns:

Port number

Throws:

java.lang.Exception

trainModel

public static void trainModel(ExternalModel model,
                              Dataset trainData)
                       throws java.lang.Exception

Make a call to the model server to train a model

Parameters:

model - Model object being trained

trainData - Data used to train model

Throws:

java.io.IOException

java.lang.Exception

java.lang.IllegalArgumentException

runModel

public static void runModel(ExternalModel model,
                            Dataset runData)
                     throws java.lang.Exception

Connect to server and run model

Parameters:

model - Model to be run

runData - Dataset to be run

Throws:

java.lang.Exception

getModelDescription

public static java.util.List<java.lang.String> getModelDescription(ExternalModel model)
                                                            throws java.lang.Error

Generate a description of the model

Parameters:

model - Model to be accessed

Returns:

List of lines of plain text describing the model settings

Throws:

java.lang.Error

stopServer

public static void stopServer(ExternalModel model)

Send the "exit" command and stop a server

Parameters:

model - Model server to be shut down