org.parboiled.buffers
Class MutableInputBuffer

java.lang.Object
  org.parboiled.buffers.MutableInputBuffer

All Implemented Interfaces:

InputBuffer

public class MutableInputBuffer
extends java.lang.Object
implements InputBuffer

An InputBuffer wrapping another InputBuffer and providing for the ability to insert (and undo) characters at certain index positions. Inserted chars do not appear in extracted text and have the same positions as the original chars at their indices. Note that this implementation is optimized for a rather small number of insertions and will perform badly with a large number of insertions.

Constructor Summary

MutableInputBuffer(InputBuffer buffer)

Method Summary

char	charAt(int index) Returns the character at the given index.
java.lang.String	extract(IndexRange range) Constructs a new String from all character covered by the given IndexRange.
java.lang.String	extract(int start, int end) Constructs a new String from all character between the given indices.
java.lang.String	extractLine(int lineNumber) Constructs a new String containing all characters with the given line number except for the trailing newline.
int	getLineCount() Returns the number of lines in the input buffer.
int	getOriginalIndex(int index) Translates the given index from the scope of this InputBuffer to the scope of the original, underlying char array.
Position	getPosition(int index) Returns the line and column number of the character with the given index encapsulated in a Position object.
void	insertChar(int index, char c)
void	replaceInsertedChar(int index, char c)
boolean	test(int index, char[] characters) Determines whether the characters starting at the given index match the ones from the given array (in order).
char	undoCharInsertion(int index)

Methods inherited from class java.lang.Object

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

Constructor Detail

MutableInputBuffer

public MutableInputBuffer(InputBuffer buffer)

Method Detail

charAt

public char charAt(int index)

Description copied from interface: InputBuffer

Returns the character at the given index. If the index is invalid the method returns Chars.EOI.

Specified by:

charAt in interface InputBuffer

Parameters:

index - the index

Returns:

the character at the given index or Chars.EOI.

test

public boolean test(int index,
                    char[] characters)

Description copied from interface: InputBuffer

Determines whether the characters starting at the given index match the ones from the given array (in order).

Specified by:

test in interface InputBuffer

Parameters:

index - the index into the input buffer where to start the comparison

characters - the characters to test against the input buffer

Returns:

true if matched

getPosition

public Position getPosition(int index)

Description copied from interface: InputBuffer

Returns the line and column number of the character with the given index encapsulated in a Position object. The very first character has the line number 1 and the column number 1.

Specified by:

getPosition in interface InputBuffer

Parameters:

index - the index of the character to get the line number of

Returns:

the line number

getOriginalIndex

public int getOriginalIndex(int index)

Description copied from interface: InputBuffer

Translates the given index from the scope of this InputBuffer to the scope of the original, underlying char array. The DefaultInputBuffer implementation simply returns the given index, but other implementations like the IndentDedentInputBuffer or the MutableInputBuffer need to "undo" all compressions and index shiftings performed internally in order to return the underlying index.

Specified by:

getOriginalIndex in interface InputBuffer

Parameters:

index - the index relative to this InputBuffer

Returns:

the index relative to the underlying string or char array

extractLine

public java.lang.String extractLine(int lineNumber)

Description copied from interface: InputBuffer

Constructs a new String containing all characters with the given line number except for the trailing newline.

Specified by:

extractLine in interface InputBuffer

Parameters:

lineNumber - the line number to get

Returns:

the string

extract

public java.lang.String extract(int start,
                                int end)

Description copied from interface: InputBuffer

Constructs a new String from all character between the given indices. Invalid indices are automatically adjusted to their respective boundary.

Specified by:

extract in interface InputBuffer

Parameters:

start - the start index (inclusively)

end - the end index (exclusively)

Returns:

a new String (non-interned)

extract

public java.lang.String extract(IndexRange range)

Description copied from interface: InputBuffer

Constructs a new String from all character covered by the given IndexRange.

Specified by:

extract in interface InputBuffer

Parameters:

range - the IndexRange

Returns:

a new String (non-interned)

getLineCount

public int getLineCount()

Description copied from interface: InputBuffer

Returns the number of lines in the input buffer.

Specified by:

getLineCount in interface InputBuffer

Returns:

number of lines in the input buffer.

insertChar

public void insertChar(int index,
                       char c)

undoCharInsertion

public char undoCharInsertion(int index)

replaceInsertedChar

public void replaceInsertedChar(int index,
                                char c)