org.owasp.esapi.codecs

Class HTMLEntityCodec

java.lang.Object

org.owasp.esapi.codecs.Codec

org.owasp.esapi.codecs.HTMLEntityCodec

public class HTMLEntityCodec
extends Codec

Implementation of the Codec interface for HTML entity encoding.

Since:

June 1, 2007

See Also:

Encoder

Field Summary

Fields

Modifier and Type	Field and Description
private static java.util.Map<java.lang.Character,java.lang.String>	characterToEntityMap
private static Trie<java.lang.Character>	entityToCharacterTrie
private static char	REPLACEMENT_CHAR
private static java.lang.String	REPLACEMENT_HEX
private static java.lang.String	REPLACEMENT_STR

Constructor Summary

Constructors

Constructor and Description
HTMLEntityCodec()

Method Summary

Modifier and Type	Method and Description
java.lang.Character	decodeCharacter(PushbackString input) Returns the decoded version of the next character from the input string and advances the current character in the PushbackString.
java.lang.String	encodeCharacter(char[] immune, java.lang.Character c) Default implementation that should be overridden in specific codecs.
private java.lang.Character	getNamedEntity(PushbackString input) Returns the decoded version of the character starting at index, or null if no decoding is possible.
private java.lang.Character	getNumericEntity(PushbackString input) getNumericEntry checks input to see if it is a numeric entity
private static java.util.Map<java.lang.Character,java.lang.String>	mkCharacterToEntityMap() Build a unmodifiable Map from entity Character to Name.
private static Trie<java.lang.Character>	mkEntityToCharacterTrie() Build a unmodifiable Trie from entitiy Name to Character
private java.lang.Character	parseHex(PushbackString input) Parse a hex encoded entity
private java.lang.Character	parseNumber(PushbackString input) Parse a decimal number, such as those from JavaScript's String.fromCharCode(value)

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

containsCharacter, decode, encode, getHexForNonAlphanumeric, toHex, toOctal

Methods inherited from class java.lang.Object

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

Field Detail

REPLACEMENT_CHAR

private static final char REPLACEMENT_CHAR

See Also:

Constant Field Values

REPLACEMENT_HEX

private static final java.lang.String REPLACEMENT_HEX

See Also:

Constant Field Values

REPLACEMENT_STR

private static final java.lang.String REPLACEMENT_STR

See Also:

Constant Field Values

characterToEntityMap

private static final java.util.Map<java.lang.Character,java.lang.String> characterToEntityMap

entityToCharacterTrie

private static final Trie<java.lang.Character> entityToCharacterTrie

Constructor Detail

HTMLEntityCodec

public HTMLEntityCodec()

Method Detail

encodeCharacter

public java.lang.String encodeCharacter(char[] immune,
                                        java.lang.Character c)

Default implementation that should be overridden in specific codecs. Encodes a Character for safe use in an HTML entity field.

Overrides:

encodeCharacter in class Codec

Parameters:

immune -

c - the Character to encode

Returns:

the encoded Character

decodeCharacter

public java.lang.Character decodeCharacter(PushbackString input)

Returns the decoded version of the next character from the input string and advances the current character in the PushbackString. If the current character is not encoded, this method MUST reset the PushbackString. Returns the decoded version of the character starting at index, or null if no decoding is possible. Formats all are legal both with and without semi-colon, upper/lower case: &#dddd; &#xhhhh; &name;

Overrides:

decodeCharacter in class Codec

Parameters:

input - the Character to decode

Returns:

the decoded Character

getNumericEntity

private java.lang.Character getNumericEntity(PushbackString input)

getNumericEntry checks input to see if it is a numeric entity

Parameters:

input - The input to test for being a numeric entity

Returns:

null if input is null, the character of input after decoding

parseNumber

private java.lang.Character parseNumber(PushbackString input)

Parse a decimal number, such as those from JavaScript's String.fromCharCode(value)

Parameters:

input - decimal encoded string, such as 65

Returns:

character representation of this decimal value, e.g. A

Throws:

java.lang.NumberFormatException

parseHex

private java.lang.Character parseHex(PushbackString input)

Parse a hex encoded entity

Parameters:

input - Hex encoded input (such as 437ae;)

Returns:

A single character from the string

Throws:

java.lang.NumberFormatException

getNamedEntity

private java.lang.Character getNamedEntity(PushbackString input)

Returns the decoded version of the character starting at index, or null if no decoding is possible. Formats all are legal both with and without semi-colon, upper/lower case: &aa; &aaa; &aaaa; &aaaaa; &aaaaaa; &aaaaaaa;

Parameters:

input - A string containing a named entity like "

Returns:

Returns the decoded version of the character starting at index, or null if no decoding is possible.

mkCharacterToEntityMap

private static java.util.Map<java.lang.Character,java.lang.String> mkCharacterToEntityMap()

Build a unmodifiable Map from entity Character to Name.

Returns:

Unmodifiable map.

mkEntityToCharacterTrie

private static Trie<java.lang.Character> mkEntityToCharacterTrie()

Build a unmodifiable Trie from entitiy Name to Character

Returns:

Unmodifiable trie.