setlocalesupport.java

来自「jakarta-taglibs」· Java 代码 · 共 464 行 · 第 1/2 页

				      boolean format,
				      Locale[] avail) {

	LocalizationContext locCtxt = null;
	
	// Get formatting locale from enclosing <fmt:bundle>
	Tag parent = findAncestorWithClass(fromTag, BundleSupport.class);
	if (parent != null) {
	    /*
	     * use locale from localization context established by parent
	     * <fmt:bundle> action, unless that locale is null
	     */
	    locCtxt = ((BundleSupport) parent).getLocalizationContext();
	    if (locCtxt.getLocale() != null) {
		if (format) {
		    setResponseLocale(pc, locCtxt.getLocale());
		}
		return locCtxt.getLocale();
	    }
	}

	// Use locale from default I18N localization context, unless it is null
	if ((locCtxt = BundleSupport.getLocalizationContext(pc)) != null) {
	    if (locCtxt.getLocale() != null) {
		if (format) {
		    setResponseLocale(pc, locCtxt.getLocale());
		}
		return locCtxt.getLocale();
	    }
	}

	/*
	 * Establish formatting locale by comparing the preferred locales
	 * (in order of preference) against the available formatting
	 * locales, and determining the best matching locale.
	 */
	Locale match = null;
	Locale pref = getLocale(pc, Config.FMT_LOCALE);
	if (pref != null) {
	    // Preferred locale is application-based
	    match = findFormattingMatch(pref, avail);
	} else {
	    // Preferred locales are browser-based 
	    match = findFormattingMatch(pc, avail);
	}
	if (match == null) {
	    //Use fallback locale.
	    pref = getLocale(pc, Config.FMT_FALLBACK_LOCALE);
	    if (pref != null) {
		match = findFormattingMatch(pref, avail);
	    }
	}
 	if (format && (match != null)) {
	    setResponseLocale(pc, match);
	}

	return match;
    }

    /**
     * Setup the available formatting locales that will be used
     * by getFormattingLocale(PageContext).
     */
    static Locale[] availableFormattingLocales;
    static {
        Locale[] dateLocales = DateFormat.getAvailableLocales();
        Locale[] numberLocales = NumberFormat.getAvailableLocales();
        Vector vec = new Vector(dateLocales.length);
        for (int i=0; i<dateLocales.length; i++) {
            for (int j=0; j<numberLocales.length; j++) {
                if (dateLocales[i].equals(numberLocales[j])) {
                    vec.add(dateLocales[i]);
                    break;
                }
            }
        }
        availableFormattingLocales = new Locale[vec.size()];
        availableFormattingLocales = (Locale[])vec.toArray(availableFormattingLocales);
        /*
        for (int i=0; i<availableFormattingLocales.length; i++) {
            System.out.println("AvailableLocale[" + i + "] " + availableFormattingLocales[i]);
        }
        */
    }
    
    /*
     * Returns the formatting locale to use when <fmt:message> is used
     * with a locale-less localization context.
     *
     * @param pc The page context containing the formatting action
     * @return the formatting locale to use
     */
    static Locale getFormattingLocale(PageContext pc) {
	/*
	 * Establish formatting locale by comparing the preferred locales
	 * (in order of preference) against the available formatting
	 * locales, and determining the best matching locale.
	 */
	Locale match = null;
	Locale pref = getLocale(pc, Config.FMT_LOCALE);
	if (pref != null) {
	    // Preferred locale is application-based
	    match = findFormattingMatch(pref, availableFormattingLocales);
	} else {
	    // Preferred locales are browser-based 
	    match = findFormattingMatch(pc, availableFormattingLocales);
	}
	if (match == null) {
	    //Use fallback locale.
	    pref = getLocale(pc, Config.FMT_FALLBACK_LOCALE);
	    if (pref != null) {
		match = findFormattingMatch(pref, availableFormattingLocales);
	    }
	}
 	if (match != null) {
	    setResponseLocale(pc, match);
	}

	return match;
    }

    /*
     * Returns the locale specified by the named scoped attribute or context
     * configuration parameter.
     *
     * <p> The named scoped attribute is searched in the page, request,
     * session (if valid), and application scope(s) (in this order). If no such
     * attribute exists in any of the scopes, the locale is taken from the
     * named context configuration parameter.
     *
     * @param pageContext the page in which to search for the named scoped
     * attribute or context configuration parameter
     * @param name the name of the scoped attribute or context configuration
     * parameter
     *
     * @return the locale specified by the named scoped attribute or context
     * configuration parameter, or <tt>null</tt> if no scoped attribute or
     * configuration parameter with the given name exists
     */
    static Locale getLocale(PageContext pageContext, String name) {
	Locale loc = null;

	Object obj = Config.find(pageContext, name);
	if (obj != null) {
	    if (obj instanceof Locale) {
		loc = (Locale) obj;
	    } else {
		loc = parseLocale((String) obj);
	    }
	}

	return loc;
    }


    //*********************************************************************
    // Private utility methods

    /*
     * Determines the client's preferred locales from the request, and compares
     * each of the locales (in order of preference) against the available
     * locales in order to determine the best matching locale.
     *
     * @param pageContext Page containing the formatting action
     * @param avail Available formatting locales
     *
     * @return Best matching locale, or <tt>null</tt> if no match was found
     */
    private static Locale findFormattingMatch(PageContext pageContext,
					      Locale[] avail) {
	Locale match = null;
	for (Enumeration enum_ = Util.getRequestLocales((HttpServletRequest)pageContext.getRequest());
	     enum_.hasMoreElements(); ) {
            Locale locale = (Locale)enum_.nextElement();
	    match = findFormattingMatch(locale, avail);
	    if (match != null) {
		break;
	    }
	}
	
	return match;
    }

    /*
     * Returns the best match between the given preferred locale and the
     * given available locales.
     *
     * The best match is given as the first available locale that exactly
     * matches the given preferred locale ("exact match"). If no exact match
     * exists, the best match is given to an available locale that meets
     * the following criteria (in order of priority):
     *  - available locale's variant is empty and exact match for both
     *    language and country
     *  - available locale's variant and country are empty, and exact match 
     *    for language.
     *
     * @param pref the preferred locale
     * @param avail the available formatting locales
     *
     * @return Available locale that best matches the given preferred locale,
     * or <tt>null</tt> if no match exists
     */
    private static Locale findFormattingMatch(Locale pref, Locale[] avail) {
	Locale match = null;
        boolean langAndCountryMatch = false;
        for (int i=0; i<avail.length; i++) {
            if (pref.equals(avail[i])) {
                // Exact match
                match = avail[i];
                break;
            } else if (
                    !"".equals(pref.getVariant()) &&
                    "".equals(avail[i].getVariant()) &&
                    pref.getLanguage().equals(avail[i].getLanguage()) &&
                    pref.getCountry().equals(avail[i].getCountry())) {
                // Language and country match; different variant
                match = avail[i];
                langAndCountryMatch = true;
            } else if (
                    !langAndCountryMatch &&
                    pref.getLanguage().equals(avail[i].getLanguage()) &&
                    ("".equals(avail[i].getCountry()))) {
                // Language match
                if (match == null) {
                    match = avail[i];
                }
            }
        }
	return match;
    }
}