com.google.template.soy.internal.i18n

Class BidiFormatter

java.lang.Object

com.google.template.soy.internal.i18n.BidiFormatter

public class BidiFormatter
extends Object

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	BidiFormatter.BidiWrappingText The text used to bidi wrap a string.

Method Summary

Modifier and Type	Method and Description
static BidiFormatter	getInstance(Dir contextDir) Factory for creating an instance of BidiFormatter given the context directionality.
String	knownDirAttr(Dir dir) Returns "dir=\"ltr\"" or "dir=\"rtl\"", depending on the given directionality, if it is not NEUTRAL or the same as the context directionality.
String	markAfter(Dir dir, String str, boolean isHtml) Returns a Unicode bidi mark matching the context directionality (LRM or RLM) if either the overall or the exit directionality of a given string is opposite to the context directionality.
String	spanWrap(Dir dir, String str, boolean isHtml) Formats a string of given directionality for use in HTML output of the context directionality, so an opposite-directionality string is neither garbled nor garbles its surroundings.
BidiFormatter.BidiWrappingText	spanWrappingText(Dir dir, String str, boolean isHtml) Operates like spanWrap(Dir, String, boolean) but only returns the text that would be prepended and appended to str.
String	unicodeWrap(Dir dir, String str, boolean isHtml) Formats a string of given directionality for use in plain-text output of the context directionality, so an opposite-directionality string is neither garbled nor garbles its surroundings.
BidiFormatter.BidiWrappingText	unicodeWrappingText(Dir dir, String str, boolean isHtml) Operates like unicodeWrap(Dir, String, boolean) but only returns the text that would be prepended and appended to str.

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static BidiFormatter getInstance(Dir contextDir)

Factory for creating an instance of BidiFormatter given the context directionality. spanWrap(com.google.template.soy.data.Dir, java.lang.String, boolean) avoids span wrapping unless there's a reason ('dir' attribute should be appended).

Parameters:

contextDir - The context directionality. Must be RTL or LTR.

knownDirAttr

public String knownDirAttr(Dir dir)

Returns "dir=\"ltr\"" or "dir=\"rtl\"", depending on the given directionality, if it is not NEUTRAL or the same as the context directionality. Otherwise, returns "".

Parameters:

dir - Given directionality. Must not be null.

Returns:

"dir=\"rtl\"" for RTL text in non-RTL context; "dir=\"ltr\"" for LTR text in non-LTR context; else, the empty string.

spanWrap

public String spanWrap(@Nullable
                       Dir dir,
                       String str,
                       boolean isHtml)

Formats a string of given directionality for use in HTML output of the context directionality, so an opposite-directionality string is neither garbled nor garbles its surroundings.

The algorithm: In case the given directionality doesn't match the context directionality, wraps the string with a 'span' element and adds a 'dir' attribute (either 'dir=\"rtl\"' or 'dir=\"ltr\"').

Directionally isolates the string so that it does not garble its surroundings. Currently, this is done by "resetting" the directionality after the string by appending a trailing Unicode bidi mark matching the context directionality (LRM or RLM) when either the overall directionality or the exit directionality of the string is opposite to that of the context. Note that as opposed to the overall directionality, the entry and exit directionalities are determined from the string itself.

If !isHtml, HTML-escapes the string regardless of wrapping.

Parameters:

dir - str's directionality. If null, i.e. unknown, it is estimated.

str - The input string

isHtml - Whether str is HTML / HTML-escaped

Returns:

Input string after applying the above processing.

spanWrappingText

public BidiFormatter.BidiWrappingText spanWrappingText(@Nullable
                                                       Dir dir,
                                                       String str,
                                                       boolean isHtml)

Operates like spanWrap(Dir, String, boolean) but only returns the text that would be prepended and appended to str.

Parameters:

dir - str's directionality. If null, i.e. unknown, it is estimated.

str - The input string

isHtml - Whether str is HTML / HTML-escaped

unicodeWrap

public String unicodeWrap(@Nullable
                          Dir dir,
                          String str,
                          boolean isHtml)

Formats a string of given directionality for use in plain-text output of the context directionality, so an opposite-directionality string is neither garbled nor garbles its surroundings. As opposed to spanWrap(com.google.template.soy.data.Dir, java.lang.String, boolean), this makes use of Unicode bidi formatting characters. In HTML, its *only* valid use is inside of elements that do not allow markup, e.g. the 'option' and 'title' elements.

The algorithm: In case the given directionality doesn't match the context directionality, wraps the string with Unicode bidi formatting characters: RLE+str+PDF for RTL text, or LRE+str+PDF for LTR text.

Directionally isolates the string so that it does not garble its surroundings. Currently, this is done by "resetting" the directionality after the string by appending a trailing Unicode bidi mark matching the context directionality (LRM or RLM) when either the overall directionality or the exit directionality of the string is opposite to that of the context. Note that as opposed to the overall directionality, the entry and exit directionalities are determined from the string itself.

Does *not* do HTML-escaping regardless of the value of isHtml.

Parameters:

dir - str's directionality. If null, i.e. unknown, it is estimated.

str - The input string

isHtml - Whether str is HTML / HTML-escaped

Returns:

Input string after applying the above processing.

unicodeWrappingText

public BidiFormatter.BidiWrappingText unicodeWrappingText(@Nullable
                                                          Dir dir,
                                                          String str,
                                                          boolean isHtml)

Operates like unicodeWrap(Dir, String, boolean) but only returns the text that would be prepended and appended to str.

Parameters:

dir - str's directionality. If null, i.e. unknown, it is estimated.

str - The input string

isHtml - Whether str is HTML / HTML-escaped

markAfter

public String markAfter(@Nullable
                        Dir dir,
                        String str,
                        boolean isHtml)

Returns a Unicode bidi mark matching the context directionality (LRM or RLM) if either the overall or the exit directionality of a given string is opposite to the context directionality. Putting this after the string (including its directionality declaration wrapping) prevents it from "sticking" to other opposite-directionality text or a number appearing after it inline with only neutral content in between. Otherwise returns the empty string. While the exit directionality is determined by scanning the end of the string, the overall directionality is given explicitly in dir.

Parameters:

str - String after which the mark may need to appear

dir - str's overall directionality. If null, i.e. unknown, it is estimated.

isHtml - Whether str is HTML / HTML-escaped

Returns:

LRM for RTL text in LTR context; RLM for LTR text in RTL context; else, the empty string.