Java tutorial
//package com.java2s; //License from project: Apache License import android.support.annotation.NonNull; import java.util.Locale; public class Main { private static final float APP_LANGUAGE_QUALITY = .9f; private static final float SYSTEM_LANGUAGE_QUALITY = .8f; /** * @return The value that should go in the Accept-Language header. */ @NonNull public static String getAcceptLanguage(@NonNull String wikiLanguageCode, @NonNull String appLanguageCode, @NonNull String systemLanguageCode) { String acceptLanguage = wikiLanguageCode; acceptLanguage = appendToAcceptLanguage(acceptLanguage, appLanguageCode, APP_LANGUAGE_QUALITY); acceptLanguage = appendToAcceptLanguage(acceptLanguage, systemLanguageCode, SYSTEM_LANGUAGE_QUALITY); return acceptLanguage; } @NonNull private static String appendToAcceptLanguage(@NonNull String acceptLanguage, @NonNull String languageCode, float quality) { // If accept-language already contains the language, just return accept-language. if (acceptLanguage.contains(languageCode)) { return acceptLanguage; } // If accept-language is empty, don't append. Just return the language. if (acceptLanguage.isEmpty()) { return languageCode; } // Accept-language is nonempty, append the language. return String.format(Locale.ROOT, "%s,%s;q=%.1f", acceptLanguage, languageCode, quality); } }