com.kprolog.plc
Class Plc

java.lang.Object
  |
  +--com.kprolog.plc.Plc

All Implemented Interfaces:

java.lang.Runnable

public class Plc

extends java.lang.Object

implements java.lang.Runnable

Plc is an interface between Java and Prolog, implemented via Java Native Interface and reflection.

Constructor Summary

Plc()
Constructs an instance representing a prolog goal.

Plc(PlcClient client, java.lang.String functor, java.lang.Object[] args)
Constructs an instance representing a prolog goal.

Plc(java.lang.String functor, java.lang.Object[] args)
Constructs an instance representing a prolog goal.

Method Summary

static java.lang.String	arrayToString(java.lang.String open, java.lang.Object[] args, java.lang.String close) Converts an array to a list style String.
boolean	call() Calls a prolog goal specified by this instance.
static boolean	exec(java.lang.String command) Parses and executes a prolog command.
java.lang.Object	getPrologResult(int n) Get the result returned from prolog for null arguments.
static void	main(java.lang.String[] args) When invoked as an application, main() starts the Prolog toplevel.
void	run() Calls a prolog goal with new thread, and find all the results.
void	setArgs(java.lang.Object[] args) Sets the arguments of the goal.
void	setFunctor(java.lang.String functor) Sets the functor name of the goal.
static void	startPlc(java.lang.String[] args) Initializes JIPL interface.
static java.lang.Object	toIntegerArray(java.lang.Object src) Convert miss interpreted string to an Integer array K-Prolog sometimes miss interprete a list of integer to a string.
java.lang.String	toString() Converts to a String representing the goal contents.

Methods inherited from class java.lang.Object

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

Constructor Detail

Plc

public Plc()

Constructs an instance representing a prolog goal.

Plc

public Plc(java.lang.String functor,
           java.lang.Object[] args)

Constructs an instance representing a prolog goal.

Parameters:

functor - functor name of the goal

args - array of arguments, prolog variables are represented by null object reference

Plc

public Plc(PlcClient client,
           java.lang.String functor,
           java.lang.Object[] args)

Constructs an instance representing a prolog goal.

Parameters:

client - reciever of result of the goal

functor - functor name of the goal

args - array of arguments, prolog variables are represented by null object reference

Method Detail

startPlc

public static void startPlc(java.lang.String[] args)

Initializes JIPL interface.

Parameters:

args - as command line options of K-Prolog
{"-a", "ATOM", "-h", "HEAP", "-l", "LOCAL", "-g", "GLOBAL"}
where ATOM etc. are the size of Prolog regions.

exec

public static boolean exec(java.lang.String command)

Parses and executes a prolog command. Deterministic.

Parameters:

command - any prolog command

Returns:

true if command sucesses, false if it fails

main

public static void main(java.lang.String[] args)

When invoked as an application, main() starts the Prolog toplevel.

Parameters:

args - passed to startPlc

See Also:

startPlc(java.lang.String[])

setFunctor

public void setFunctor(java.lang.String functor)

Sets the functor name of the goal.

Parameters:

functor - functor name of the goal

setArgs

public void setArgs(java.lang.Object[] args)

Sets the arguments of the goal.

Parameters:

args - array of arguments

call

public boolean call()

Calls a prolog goal specified by this instance. Deterministic.

Returns:

true if the goal sucesses, false if it fails

run

public void run()

Calls a prolog goal with new thread, and find all the results. Results are passed to the client object.

Specified by:

run in interface java.lang.Runnable

See Also:

PlcClient.success(java.lang.Object[]), PlcClient.fail()

getPrologResult

public java.lang.Object getPrologResult(int n)

Get the result returned from prolog for null arguments.

Parameters:

n - position of argument (0 to args.length-1)

toIntegerArray

public static java.lang.Object toIntegerArray(java.lang.Object src)

Convert miss interpreted string to an Integer array K-Prolog sometimes miss interprete a list of integer to a string. This is very difficult to fix, because Prolog string is a list of integer character codes. For example, [3110] is an list of integer, but this also represents my name -kino in kanji- as a string. So, we may reinterprete it to an Integer array in such case.

Parameters:

src - an argument returned from prolog

Returns:

an Integer array

toString

public java.lang.String toString()

Converts to a String representing the goal contents.

Overrides:

toString in class java.lang.Object

arrayToString

public static java.lang.String arrayToString(java.lang.String open,
                                             java.lang.Object[] args,
                                             java.lang.String close)

Converts an array to a list style String.