com.jn.langx.util.escape

类 ArrayBasedUnicodeEscaper

java.lang.Object

com.jn.langx.util.escape.UnicodeEscaper

com.jn.langx.util.escape.ArrayBasedUnicodeEscaper

所有已实现的接口:

Escaper

public abstract class ArrayBasedUnicodeEscaper
extends UnicodeEscaper

A UnicodeEscaper that uses an array to quickly look up replacement characters for a given code point. An additional safe range is provided that determines whether code points 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 HTML escaping where the replacement array contains information about the named HTML entities such as & and " while escapeUnsafe(int) is overridden to handle general escaping of the form &#NNNNN;.

The size of the data structure used by ArrayBasedUnicodeEscaper is proportional to the highest valued code point 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.

构造器概要

构造器

限定符	构造器和说明
protected	ArrayBasedUnicodeEscaper(ArrayBasedEscaperMap escaperMap, int safeMin, int safeMax, String unsafeReplacement) Creates a new ArrayBasedUnicodeEscaper instance with the given replacement map and specified safe range.
protected	ArrayBasedUnicodeEscaper(Map<Character,String> replacementMap, int safeMin, int safeMax, String unsafeReplacement) Creates a new ArrayBasedUnicodeEscaper instance with the given replacement map and specified safe range.

方法概要

限定符和类型	方法和说明
protected char[]	escape(int cp) Escapes a single Unicode code point using the replacement array and safe range values.
String	escape(String s) This is overridden to improve performance.
protected abstract char[]	escapeUnsafe(int cp) Escapes a code point that has no direct explicit value in the replacement array and lies outside the stated safe range.
protected int	nextEscapeIndex(CharSequence csq, int index, int end) Overridden for performance.

从类继承的方法 com.jn.langx.util.escape.UnicodeEscaper

codePointAt, escapeSlow

从类继承的方法 java.lang.Object

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

构造器详细资料

ArrayBasedUnicodeEscaper

protected ArrayBasedUnicodeEscaper(Map<Character,String> replacementMap,
                                   int safeMin,
                                   int safeMax,
                                   @Nullable
                                   String unsafeReplacement)

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

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

参数:

replacementMap - a map of characters to their escaped representations

safeMin - the lowest character value in the safe range

safeMax - the highest character value in the safe range

unsafeReplacement - the default replacement for unsafe characters or null if no default replacement is required

ArrayBasedUnicodeEscaper

protected ArrayBasedUnicodeEscaper(ArrayBasedEscaperMap escaperMap,
                                   int safeMin,
                                   int safeMax,
                                   @Nullable
                                   String unsafeReplacement)

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

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

参数:

escaperMap - the map of replacements

safeMin - the lowest character value in the safe range

safeMax - the highest character value in the safe range

unsafeReplacement - the default replacement for unsafe characters or null if no default replacement is required

方法详细资料

escape

public final String escape(String s)

This is overridden to improve performance. Rough benchmarking shows that this almost doubles the speed when processing strings that do not require any escaping.

指定者:

escape 在接口中 Escaper

覆盖:

escape 在类中 UnicodeEscaper

参数:

s - the literal string to be escaped

返回:

the escaped form of string

escape

protected final char[] escape(int cp)

Escapes a single Unicode code point 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(int) is called.

指定者:

escape 在类中 UnicodeEscaper

参数:

cp - the Unicode code point to escape if necessary

返回:

the replacement characters, or null if no escaping was needed

nextEscapeIndex

protected final int nextEscapeIndex(CharSequence csq,
                                    int index,
                                    int end)

Overridden for performance.

覆盖:

nextEscapeIndex 在类中 UnicodeEscaper

参数:

csq - a sequence of characters

index - the index of the first character to be scanned

end - the index immediately after the last character to be scanned

escapeUnsafe

protected abstract char[] escapeUnsafe(int cp)

Escapes a code point 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 code points if required.

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).

参数:

cp - the Unicode code point to escape

返回:

the replacement characters, or null if no escaping was required