!5 update I18nLocaleResolver.java.

Merge pull request !5 from 老周/N/A

im-admin/ruoyi-common/ruoyi-common-web/src/main/java/org/dromara/common/web/core/I18nLocaleResolver.java

@@ -15,12 +15,35 @@ public class I18nLocaleResolver implements LocaleResolver {
 
     @Override
     public Locale resolveLocale(HttpServletRequest httpServletRequest) {
-        String language = httpServletRequest.getHeader("content-language");
-        Locale locale = Locale.getDefault();
-        if (language != null && language.length() > 0) {
-            String[] split = language.split("_");
-            locale = new Locale(split[0], split[1]);
+        String languageHeader = httpServletRequest.getHeader("content-language");
+        Locale locale;
+
+        if (languageHeader != null && !languageHeader.isEmpty()) {
+            // 处理可能的逗号分隔的语言列表
+            String[] languages = languageHeader.split(",");
+            String preferredLanguage = languages[0]; // 取第一个语言标签作为首选
+
+            // 处理语言标签的格式（可能包含语言、国家、区域）
+            String[] parts = preferredLanguage.split("-");
+            switch (parts.length) {
+                case 1: // 只有语言代码
+                    locale = new Locale(parts[0]);
+                    break;
+                case 2: // 语言代码和国家代码
+                    locale = new Locale(parts[0], parts[1]);
+                    break;
+                case 3: // 语言代码、国家代码和区域代码
+                    locale = new Locale(parts[0], parts[1], parts[2]);
+                    break;
+                default: // 默认回退到默认语言环境
+                    locale = Locale.getDefault();
+                    break;
             }
+        } else {
+            // 如果没有 content-language 头部，使用默认语言环境
+            locale = Locale.getDefault();
+        }
+
         return locale;
     }