【fix sonar】 I18nUtil.java文件

jero-boot/jero-cloud-module/jero-cloud-xxljob/src/main/java/com/xxl/job/admin/core/util/I18nUtil.java

@@ -20,6 +20,9 @@ import java.util.Properties;
  * @author xuxueli 2018-01-17 20:39:06
  */
 public class I18nUtil {
+    private I18nUtil() {
+    }
+
     private static Logger logger = LoggerFactory.getLogger(I18nUtil.class);
 
     private static Properties prop = null;
@@ -49,7 +52,11 @@ public class I18nUtil {
      * @return
      */
     public static String getString(String key) {
-        return loadI18nProp().getProperty(key);
+        Properties properties = loadI18nProp();
+        if(properties!=null&&properties.getProperty(key)!=null){
+            return properties.getProperty(key);
+        }
+        return "";
     }
 
     /**
@@ -59,21 +66,24 @@ public class I18nUtil {
      * @return
      */
     public static String getMultString(String... keys) {
-        Map<String, String> map = new HashMap<String, String>();
+        Map<String, String> map = new HashMap<>();
 
         Properties prop = loadI18nProp();
         if (keys!=null && keys.length>0) {
             for (String key: keys) {
-                map.put(key, prop.getProperty(key));
+                if(prop!=null) {
+                    map.put(key, prop.getProperty(key));
+                }
             }
         } else {
-            for (String key: prop.stringPropertyNames()) {
-                map.put(key, prop.getProperty(key));
+            if(prop!=null){
+                for (String key : prop.stringPropertyNames()) {
+                    map.put(key, prop.getProperty(key));
+                }
             }
         }
 
-        String json = JacksonUtil.writeValueAsString(map);
-        return json;
+        return JacksonUtil.writeValueAsString(map);
     }
 
 }