Guava: Google Core Libraries for Java 33.1.0-jre · com.google.common.escape.ArrayBasedCharEscaper

A CharEscaper that uses an array to quickly look up replacement characters for a given char value. An additional safe range is provided that determines whether char values without specific replacements are to be considered safe and left unescaped or should be escaped in a general way.

A good example of usage of this class is for Java source code escaping where the replacement array contains information about special ASCII characters such as \\t and \\n while escapeUnsafe is overridden to handle general escaping of the form \\uxxxx.

The size of the data structure used by ArrayBasedCharEscaper is proportional to the highest valued character that requires escaping. For example a replacement map containing the single character '\u1000' will require approximately 16K of memory. If you need to create multiple escaper instances that have the same character replacement mapping consider using ArrayBasedEscaperMap.

Modifier and Type	Field and Description
private final char[][]	replacements
private final int	replacementsLength
private final char	safeMax
private final char	safeMin

Constructor Summary

Access	Constructor and Description
protected	ArrayBasedCharEscaper(Map<Character, String> a map of characters to their escaped representations replacementMap, char the lowest character value in the safe range safeMin, char the highest character value in the safe range safeMax) Creates a new ArrayBasedCharEscaper instance with the given replacement map and specified safe range.
protected	ArrayBasedCharEscaper(ArrayBasedEscaperMap the mapping of characters to be escaped escaperMap, char the lowest character value in the safe range safeMin, char the highest character value in the safe range safeMax) Creates a new ArrayBasedCharEscaper instance with the given replacement map and specified safe range.

Method Summary

Modifier and Type	Method and Description
public final String	escape(String the literal string to be escaped s) Overrides com.google.common.escape.CharEscaper.escape. Returns the escaped form of a given literal string.
protected final char[]	Returns: the replacement characters, or `null` if no escaping was required escape(char the character to escape if necessary c) Implements abstract com.google.common.escape.CharEscaper.escape. Escapes a single character using the replacement array and safe range values.
protected abstract char[]	Returns: the replacement characters, or `null` if no escaping was required escapeUnsafe(char the character to escape c) Escapes a `char` value that has no direct explicit value in the replacement array and lies outside the stated safe range.

Inherited from com.google.common.escape.CharEscaper:: escapeSlow

Field Detail

replacements	back to summary
private final char[][] replacements

replacementsLength	back to summary
private final int replacementsLength

safeMax	back to summary
private final char safeMax

safeMin	back to summary
private final char safeMin

Constructor Detail

ArrayBasedCharEscaper back to summary

ArrayBasedCharEscaper	back to summary
protected ArrayBasedCharEscaper(Map<Character, String> replacementMap, char safeMin, char safeMax) Creates a new ArrayBasedCharEscaper instance with the given replacement map and specified safe range. If `safeMax < safeMin` then no characters are considered safe. If a character has no mapped replacement then it is checked against the safe range. If it lies outside that, then `escapeUnsafe` is called, otherwise no escaping is performed. Parameters replacementMap:Map<Character, String> a map of characters to their escaped representations safeMin:char the lowest character value in the safe range safeMax:char the highest character value in the safe range

protected ArrayBasedCharEscaper(Map<Character, String> replacementMap, char safeMin, char safeMax)

Creates a new ArrayBasedCharEscaper instance with the given replacement map and specified safe range. If safeMax < safeMin then no characters are considered safe.

If a character has no mapped replacement then it is checked against the safe range. If it lies outside that, then escapeUnsafe is called, otherwise no escaping is performed.

Parameters

replacementMap:Map<Character, String>: a map of characters to their escaped representations
safeMin:char: the lowest character value in the safe range
safeMax:char: the highest character value in the safe range

ArrayBasedCharEscaper back to summary

ArrayBasedCharEscaper	back to summary
protected ArrayBasedCharEscaper(ArrayBasedEscaperMap escaperMap, char safeMin, char safeMax) Creates a new ArrayBasedCharEscaper instance with the given replacement map and specified safe range. If `safeMax < safeMin` then no characters are considered safe. This initializer is useful when explicit instances of ArrayBasedEscaperMap are used to allow the sharing of large replacement mappings. If a character has no mapped replacement then it is checked against the safe range. If it lies outside that, then `escapeUnsafe` is called, otherwise no escaping is performed. Parameters escaperMap:ArrayBasedEscaperMap the mapping of characters to be escaped safeMin:char the lowest character value in the safe range safeMax:char the highest character value in the safe range

protected ArrayBasedCharEscaper(ArrayBasedEscaperMap escaperMap, char safeMin, char safeMax)

Creates a new ArrayBasedCharEscaper instance with the given replacement map and specified safe range. If safeMax < safeMin then no characters are considered safe. This initializer is useful when explicit instances of ArrayBasedEscaperMap are used to allow the sharing of large replacement mappings.

If a character has no mapped replacement then it is checked against the safe range. If it lies outside that, then escapeUnsafe is called, otherwise no escaping is performed.

Parameters

escaperMap:ArrayBasedEscaperMap: the mapping of characters to be escaped
safeMin:char: the lowest character value in the safe range
safeMax:char: the highest character value in the safe range

Method Detail

escape back to summary

escape	back to summary
public final String escape(String s) Overrides com.google.common.escape.CharEscaper.escape. Doc from com.google.common.escape.CharEscaper.escape. Returns the escaped form of a given literal string. Parameters s:String the literal string to be escaped Returns:String the escaped form of `string` Annotations @Override

public final String escape(String s)

Overrides com.google.common.escape.CharEscaper.escape.

Doc from com.google.common.escape.CharEscaper.escape.

Returns the escaped form of a given literal string.

Parameters

s:String: the literal string to be escaped

Returns:String

the escaped form of string

Annotations

@Override

escape back to summary

escape	back to summary
protected final char[] escape(char c) Implements abstract com.google.common.escape.CharEscaper.escape. Escapes a single character using the replacement array and safe range values. If the given character does not have an explicit replacement and lies outside the safe range then `escapeUnsafe` is called. Parameters c:char Doc from com.google.common.escape.CharEscaper.escape. the character to escape if necessary Returns:char[] the replacement characters, or `null` if no escaping was required Annotations @Override @CheckForNull

protected final char[] escape(char c)

Implements abstract com.google.common.escape.CharEscaper.escape.

Escapes a single character using the replacement array and safe range values. If the given character does not have an explicit replacement and lies outside the safe range then escapeUnsafe is called.

Parameters

c:char

Doc from com.google.common.escape.CharEscaper.escape.

the character to escape if necessary

Returns:char[]

the replacement characters, or null if no escaping was required

Annotations

@Override
@CheckForNull

escapeUnsafe back to summary

escapeUnsafe	back to summary
protected abstract char[] escapeUnsafe(char c) Escapes a `char` value that has no direct explicit value in the replacement array and lies outside the stated safe range. Subclasses should override this method to provide generalized escaping for characters. Note that arrays returned by this method must not be modified once they have been returned. However it is acceptable to return the same array multiple times (even for different input characters). Parameters c:char the character to escape Returns:char[] the replacement characters, or `null` if no escaping was required Annotations @CheckForNull

protected abstract char[] escapeUnsafe(char c)

Escapes a char value that has no direct explicit value in the replacement array and lies outside the stated safe range. Subclasses should override this method to provide generalized escaping for characters.

Note that arrays returned by this method must not be modified once they have been returned. However it is acceptable to return the same array multiple times (even for different input characters).

Parameters

c:char: the character to escape

Returns:char[]

the replacement characters, or null if no escaping was required

Annotations

@CheckForNull

public abstract Class ArrayBasedCharEscaper

Field Summary

Constructor Summary

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Field Detail

Constructor Detail

Method Detail