com.svincent.moksa
Class Io.PrologInput

java.lang.Object
  |
  +--com.svincent.moksa.WamObject
        |
        +--com.svincent.moksa.PrologTerm
              |
              +--com.svincent.moksa.Io.StreamIdentifier
                    |
                    +--com.svincent.moksa.Io.PrologInput

All Implemented Interfaces:

Trailable

Direct Known Subclasses:

Io.PrologInputStream, Io.PrologReader

Enclosing class:

Io

public abstract static class Io.PrologInput

extends Io.StreamIdentifier

An identifier for an input stream.

Fields inherited from class com.svincent.moksa.PrologTerm

EmptyArray

Constructor Summary

Io.PrologInput(Io _io, java.lang.String _fileName, CompoundTerm _options)
Opens the file.

Method Summary

abstract void	close()
void	consume(int c) If 'c' is the next character in the stream, read and discard it.
void	flush()
int	getMode()
boolean	isInput()
boolean	lookahead(int n, int c) Returns 'true' iff the character 'c' is 'n' characters ahead in this stream.
int	peekChar() Returns the character which will be returned from the next call to 'readChar'.
int	peekChar(int n) Peeks n chars ahead.
void	pushbackChar(int c) Pushes a character back into the stream.
int	readChar() Reads a character from this stream.
abstract int	readCharImpl()
PrologTerm	readCharTerm() Returns the next character in the stream as a PrologTerm (either an Integer or an Atom: 'end_of_file').

Methods inherited from class com.svincent.moksa.Io.StreamIdentifier

clonePrologTerm, getName, getOptions, getUri, isOpen, isOutput, isStreamId, unify

Methods inherited from class com.svincent.moksa.PrologTerm

accept, clonePrologTerm, deref, evaluateExpression, floatValue, getArity, getNameConstant, getPriority, intValue, isAtom, isCompoundTerm, isConstant, isEmptyList, isFloat, isInteger, isJavaObject, isList, isNonEmptyList, isStructure, isVariable, printVariables, setPriority, unify, unifyWithoutBindings, untrail

Methods inherited from class com.svincent.moksa.WamObject

tag, tag

Methods inherited from class java.lang.Object

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

Constructor Detail

Io.PrologInput

public Io.PrologInput(Io _io,
                      java.lang.String _fileName,
                      CompoundTerm _options)

Opens the file.

Method Detail

getMode

public int getMode()

Overrides:

getMode in class Io.StreamIdentifier

isInput

public boolean isInput()

Overrides:

isInput in class Io.StreamIdentifier

readCharImpl

public abstract int readCharImpl()
                          throws java.io.IOException

close

public abstract void close()
                    throws java.io.IOException

Overrides:

close in class Io.StreamIdentifier

readCharTerm

public PrologTerm readCharTerm()
                        throws java.io.IOException

Returns the next character in the stream as a PrologTerm (either an Integer or an Atom: 'end_of_file').

peekChar

public int peekChar()
             throws java.io.IOException

Returns the character which will be returned from the next call to 'readChar'.

peekChar

public int peekChar(int n)
             throws java.io.IOException

Peeks n chars ahead.

peekChar (1) == peekChar ()

consume

public void consume(int c)
             throws java.io.IOException

If 'c' is the next character in the stream, read and discard it. If it is not, do not read it, and throw an exception.

lookahead

public boolean lookahead(int n,
                         int c)
                  throws java.io.IOException

Returns 'true' iff the character 'c' is 'n' characters ahead in this stream.

pushbackChar

public void pushbackChar(int c)
                  throws java.io.IOException

Pushes a character back into the stream. This character will be read again later.

XXX export this functionality to Prolog.

readChar

public int readChar()
             throws java.io.IOException

Reads a character from this stream.

flush

public void flush()
           throws java.io.IOException

Overrides:

flush in class Io.StreamIdentifier