2.3.1 API误用：缺少对方法返回值的null检查

license/src/main/java/iot/sixiang/license/util/CommonUtil.java

@@ -85,11 +85,14 @@ public class CommonUtil {
 	public static String getLibFilePathByFileName(String fileName) {
 		String os = System.getProperty("os.name");
 		String serverParentDirectory = getServerParentDirectory();
+		if (os != null) {
 			if (os.toLowerCase(Locale.ENGLISH).startsWith("win")) {
 				return serverParentDirectory + File.separator + "lib" + File.separator + fileName + ".dll";
 			} else {
 				return serverParentDirectory + File.separator + "lib" + File.separator + fileName + ".so";
 			}
 		}
+		return "";
+	}
 
 }