org.owasp.esapi.codecs

Class PushbackString

java.lang.Object

org.owasp.esapi.codecs.AbstractPushbackSequence<Character>

org.owasp.esapi.codecs.PushbackString

All Implemented Interfaces:

PushbackSequence<Character>

public class PushbackString
extends AbstractPushbackSequence<Character>

The pushback string is used by Codecs to allow them to push decoded characters back onto a string for further decoding. This is necessary to detect double-encoding.

Since:

June 1, 2007

Author:

Jeff Williams (jeff.williams .at. aspectsecurity.com) Aspect Security

See Also:

Encoder

Field Summary

Fields inherited from class org.owasp.esapi.codecs.AbstractPushbackSequence

index, input, mark, pushback, temp

Constructor Summary

Constructors

Constructor and Description
PushbackString(String input)

Method Summary

Modifier and Type	Method and Description
boolean	hasNext() Determine if this sequence has another element.
int	index() Get the current index of the PushbackString.
static boolean	isHexDigit(Character c) Returns true if the parameter character is a hexidecimal digit 0 through 9, a through f, or A through F.
static boolean	isOctalDigit(Character c) Returns true if the parameter character is an octal digit 0 through 7.
void	mark() Mark the location of the current index.
Character	next() Return the next element in the Sequence and increment the current index.
Character	nextHex() Return the next element in the Sequence in Hex format and increment the current index.
Character	nextOctal() Return the next element in the Sequence in Octal format and increment the current index.
Character	peek() Return the next element in the Sequence without affecting the current index.
boolean	peek(Character c) Test to see if the next element in the Sequence matches the supplied value without affecting the current index.
String	remainder() Not at all sure what this method is intended to do.
void	reset() Set the index back to the last marked location.

Methods inherited from class org.owasp.esapi.codecs.AbstractPushbackSequence

pushback

Methods inherited from class java.lang.Object

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

Constructor Detail

PushbackString

public PushbackString(String input)

Parameters:

input - Construct a PushbackString with the specified String.

Method Detail

index

public int index()

Description copied from class: AbstractPushbackSequence

Get the current index of the PushbackString. Typically used in error messages.

Specified by:

index in interface PushbackSequence<Character>

Overrides:

index in class AbstractPushbackSequence<Character>

Returns:

The current index of the PushbackSequence.

hasNext

public boolean hasNext()

Description copied from class: AbstractPushbackSequence

Determine if this sequence has another element.

Specified by:

hasNext in interface PushbackSequence<Character>

Overrides:

hasNext in class AbstractPushbackSequence<Character>

Returns:

True if there is another element in this sequence. False otherwise.

next

public Character next()

Description copied from interface: PushbackSequence

Return the next element in the Sequence and increment the current index.

Returns:

The next element in the Sequence.

nextHex

public Character nextHex()

Description copied from interface: PushbackSequence

Return the next element in the Sequence in Hex format and increment the current index.

Returns:

The next element in the Sequence in Hex format (if that makes sense for this Sequence's type).

nextOctal

public Character nextOctal()

Description copied from interface: PushbackSequence

Return the next element in the Sequence in Octal format and increment the current index.

Returns:

The next element in the Sequence in Octal format (if that makes sense for this Sequence's type).

isHexDigit

public static boolean isHexDigit(Character c)

Returns true if the parameter character is a hexidecimal digit 0 through 9, a through f, or A through F.

Parameters:

c -

Returns:

true if it is a hexidecimal digit, false otherwise.

isOctalDigit

public static boolean isOctalDigit(Character c)

Returns true if the parameter character is an octal digit 0 through 7.

Parameters:

c -

Returns:

true if it is an octal digit, false otherwise.

peek

public Character peek()

Description copied from interface: PushbackSequence

Return the next element in the Sequence without affecting the current index.

Returns:

the next element in the Sequence.

peek

public boolean peek(Character c)

Description copied from interface: PushbackSequence

Test to see if the next element in the Sequence matches the supplied value without affecting the current index.

Parameters:

c - The value to match against.

Returns:

True if the next element matches the supplied value. False otherwise.

mark

public void mark()

Mark the location of the current index.

reset

public void reset()

Set the index back to the last marked location.

remainder

public String remainder()

Not at all sure what this method is intended to do. There is a line in HTMLEntityCodec that said calling this method is a "kludge around PushbackString..."

Returns:

Return the remaining portion of the sequence, with any pushback appended to the front (if any).