Package org.smtlib

Class CharSequenceInfinite

java.lang.Object

org.smtlib.CharSequenceInfinite

All Implemented Interfaces:

CharSequence

Direct Known Subclasses:

CharSequenceReader, CharSequenceSocket

public abstract class CharSequenceInfinite
extends Object
implements CharSequence

This class implements a CharSequence that obtains its characters from a source of characters of unknown length; it also provides some functionality to retain the characters and compute line numbers.

The characters read are held in an internal char array, whose size grows as needed; it starts as initialSize and is expanded to currentSize*sizeMultiple + sizeIncrease whenever needed.

The CharSequenceReader is an unconventional CharSequence in that its length() is not known; whether this will cause problems in some uses of the CharSequenceReader is unknown. The user should not use the value of length() directly; it seems to work in the ways it is called from Pattern.matcher.

Author:

David R. Cok

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	CharSequenceInfinite.IPrompter	This interface is used to create prompters.

Field Summary

Fields

Modifier and Type	Field	Description
protected int	amountRead	The number of characters read so far (and in the char array)
protected char[]	buf	The internal char array that holds characters as they are read
static final char	endChar	The character to use to mark the end of input
protected int	length	The implicit length of the CharSequence; note that this length may change as characters are read
CharSequenceInfinite.IPrompter	prompter	The prompter object
protected int	sizeIncrease	The amount by which to increase the internal char array when needed
protected double	sizeMultiple	The factor by which to increase the size of the internal char array when needed

Constructor Summary

Constructors

Constructor	Description
CharSequenceInfinite(int initialSize, int sizeIncrease, double sizeMultiple)	Constructor for a new instance

Method Summary

Modifier and Type	Method	Description
char	charAt(int index)	Returns the char at the given index; this may block while input is read if the char has not been read before.
int	length()	Returns the length of the CharSequence; for this implementation, the return value is at least as great as the unknown length of the CharSequence.
protected abstract boolean	readChars()	Reads more characters into the buffer; may block until some are read; returns false if end of input has been reached, in which case no additional chars should have been read.
CharSequence	subSequence(int start, int end)	Returns a subsequence of this CharSequence, of length end-start.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.CharSequence

chars, codePoints, isEmpty, toString

Field Details

prompter

public CharSequenceInfinite.IPrompter prompter

The prompter object

sizeIncrease

protected int sizeIncrease

The amount by which to increase the internal char array when needed

sizeMultiple

protected double sizeMultiple

The factor by which to increase the size of the internal char array when needed

buf

protected char[] buf

The internal char array that holds characters as they are read

amountRead

protected int amountRead

The number of characters read so far (and in the char array)

length

protected int length

The implicit length of the CharSequence; note that this length may change as characters are read

endChar

public static final char endChar

The character to use to mark the end of input

See Also:

• Constant Field Values

Constructor Details

CharSequenceInfinite

public CharSequenceInfinite(int initialSize,
 int sizeIncrease,
 double sizeMultiple)

Constructor for a new instance

Parameters:

initialSize - the beginning size of the internal char array

sizeIncrease - the amount to add to the current size of the internal char array when the array needs expanding

sizeMultiple - the factor by which to multiply the current size of the internal char array when it needs expanding

Method Details

charAt

public char charAt(int index)

Returns the char at the given index; this may block while input is read if the char has not been read before. An IOException that occurs while reading input is converted to an undeclared RuntimeException.

Specified by:

charAt in interface CharSequence

readChars

protected abstract boolean readChars()
                              throws IOException

Reads more characters into the buffer; may block until some are read; returns false if end of input has been reached, in which case no additional chars should have been read. Does not expand the buffer, so the buffer must have extra space in it when readChars() is called.

Returns:

true if characters were read, false if no chars were read and end of input was reached

Throws:

IOException

length

public int length()

Returns the length of the CharSequence; for this implementation, the return value is at least as great as the unknown length of the CharSequence. The value is correct once the end of input has been reached.

Specified by:

length in interface CharSequence

Returns:

the length of the CharSequence

subSequence

public CharSequence subSequence(int start,
 int end)

Returns a subsequence of this CharSequence, of length end-start. CAUTION: This method can wrap a portion of the internal char array, but then the char array can be expanded, allocating a new char array - so just don't rely on changes to the sub-sequence to be reflected in the parent array.

Specified by:

subSequence in interface CharSequence

Parameters:

start - the starting index of the subsequence

end - one past the last character included in the subsequence