Package org.projog.core.predicate.builtin.io

Class Open

java.lang.Object

org.projog.core.predicate.AbstractSingleResultPredicate

org.projog.core.predicate.builtin.io.Open

All Implemented Interfaces:

KnowledgeBaseConsumer, PredicateFactory

public final class Open
extends AbstractSingleResultPredicate

open(X,Y,Z) - opens a file.

X is an atom representing the name of the file to open. Y is an atom that should have either the value read to open the file for reading from or write to open the file for writing to. Z is instantiated by open to a special term that must be referred to in subsequent commands in order to access the stream.

Field Summary

Fields

Modifier and Type	Field	Description
private static java.lang.String	READ
private static java.lang.String	WRITE

Constructor Summary

Constructors

Constructor	Description
Open()

Method Summary

Modifier and Type	Method	Description
protected boolean	evaluate(Term fileNameAtom, Term operationAtom, Term variableToAssignTo)
private Atom	openInput(java.lang.String fileName)
private Atom	openOutput(java.lang.String fileName)

Methods inherited from class org.projog.core.predicate.AbstractSingleResultPredicate

evaluate, evaluate, evaluate, evaluate, evaluate, getArithmeticOperators, getFileHandles, getKnowledgeBase, getOperands, getPredicate, getPredicates, getProjogListeners, getSpyPoints, getTermFormatter, init, isRetryable, setKnowledgeBase

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.projog.core.predicate.PredicateFactory

isAlwaysCutOnBacktrack

Field Detail

READ

private static final java.lang.String READ

See Also:

Constant Field Values

WRITE

private static final java.lang.String WRITE

See Also:

Constant Field Values

Constructor Detail

Open

public Open()

Method Detail

evaluate

protected boolean evaluate(Term fileNameAtom,
                           Term operationAtom,
                           Term variableToAssignTo)

Overrides:

evaluate in class AbstractSingleResultPredicate

openInput

private Atom openInput(java.lang.String fileName)

openOutput

private Atom openOutput(java.lang.String fileName)