diff --git a/interfaces/kits/js/src/common/napi/n_class.cpp b/interfaces/kits/js/src/common/napi/n_class.cpp
index 482bd7807b9f5be54b74bf9c38cd57c6253a46a8..34dfdbbc6fd15d6c77401685ebd0c22129e29aca 100644
--- a/interfaces/kits/js/src/common/napi/n_class.cpp
+++ b/interfaces/kits/js/src/common/napi/n_class.cpp
@@ -19,15 +19,10 @@
 #include <sstream>
 
 #include "../log.h"
-
+#include "singleton.h"
 namespace OHOS {
 namespace DistributedFS {
 using namespace std;
-NClass &NClass::GetInstance()
-{
-    static thread_local NClass nClass;
-    return nClass;
-}
 
 tuple<bool, napi_value> NClass::DefineClass(napi_env env,
                                             string className,
@@ -51,17 +46,17 @@ tuple<bool, napi_value> NClass::DefineClass(napi_env env,
 
 bool NClass::SaveClass(napi_env env, string className, napi_value exClass)
 {
-    NClass &nClass = NClass::GetInstance();
-    lock_guard(nClass.exClassMapLock);
+  
+    lock_guard(exClassMapLock);
 
-    if (nClass.exClassMap.find(className) != nClass.exClassMap.end()) {
+    if (exClassMap.find(className) != exClassMap.end()) {
         return true;
     }
 
     napi_ref constructor;
     napi_status res = napi_create_reference(env, exClass, 1, &constructor);
     if (res == napi_ok) {
-        nClass.exClassMap.insert({ className, constructor });
+        exClassMap.insert({ className, constructor });
         HILOGI("Class %{public}s has been saved", className.c_str());
     } else {
         HILOGE("INNER BUG. Cannot ref class constructor %{public}s because of %{public}d", className.c_str(), res);
@@ -72,10 +67,9 @@ bool NClass::SaveClass(napi_env env, string className, napi_value exClass)
 
 napi_value NClass::InstantiateClass(napi_env env, const string& className, const vector<napi_value>& args)
 {
-    NClass &nClass = NClass::GetInstance();
-    lock_guard(nClass.exClassMapLock);
-    auto it = nClass.exClassMap.find(className);
-    if (it == nClass.exClassMap.end()) {
+    lock_guard(exClassMapLock);
+    auto it = exClassMap.find(className);
+    if (it == exClassMap.end()) {
         HILOGE("Class %{public}s hasn't been saved yet", className.c_str());
         return nullptr;
     }
diff --git a/interfaces/kits/js/src/common/napi/n_class.h b/interfaces/kits/js/src/common/napi/n_class.h
index 13a194ade3728777444816f0c451c1a1a26f7e8f..b0f511bf745025bf6290dd158291c9fb9938b12c 100644
--- a/interfaces/kits/js/src/common/napi/n_class.h
+++ b/interfaces/kits/js/src/common/napi/n_class.h
@@ -24,12 +24,11 @@
 
 namespace OHOS {
 namespace DistributedFS {
-class NClass final {
+class NClass : public Singleton<NClass>{
 public:
     NClass(const NClass &) = delete;
     NClass &operator = (const NClass &) = delete;
-    static NClass &GetInstance();
-
+    
     static std::tuple<bool, napi_value> DefineClass(napi_env env,
                                                     std::string className,
                                                     napi_callback constructor,
diff --git a/interfaces/kits/js/src/mod_fileio/class_constants/constants.cpp b/interfaces/kits/js/src/mod_fileio/class_constants/constants.cpp
index f046d8e849d58b86c07cab27d068a227cbb98b86..834e2dd8e1851ee9c2d1f518e372a01231b97487 100644
--- a/interfaces/kits/js/src/mod_fileio/class_constants/constants.cpp
+++ b/interfaces/kits/js/src/mod_fileio/class_constants/constants.cpp
@@ -164,12 +164,12 @@ bool Constants::Export()
     string className = GetClassName();
     bool succ = false;
     napi_value classValue = nullptr;
-    tie(succ, classValue) = NClass::DefineClass(exports_.env_, className, Constants::Constructor, std::move(props));
+    tie(succ, classValue) = NClass::GetInstance().DefineClass(exports_.env_, className, Constants::Constructor, std::move(props));
     if (!succ) {
         UniError(EIO).ThrowErr(exports_.env_, "INNER BUG. Failed to define class");
         return false;
     }
-    succ = NClass::SaveClass(exports_.env_, className, classValue);
+    succ = NClass::GetInstance().SaveClass(exports_.env_, className, classValue);
     if (!succ) {
         UniError(EIO).ThrowErr(exports_.env_, "INNER BUG. Failed to save class");
         return false;
diff --git a/interfaces/kits/js/src/mod_fileio/class_dir/dir_n_exporter.cpp b/interfaces/kits/js/src/mod_fileio/class_dir/dir_n_exporter.cpp
index ed53fb3ea98a95b03ae4d104a43161078487f83e..33c3eca71ad4325d3a38cebe8e39a46b8414fbf9 100644
--- a/interfaces/kits/js/src/mod_fileio/class_dir/dir_n_exporter.cpp
+++ b/interfaces/kits/js/src/mod_fileio/class_dir/dir_n_exporter.cpp
@@ -443,13 +443,13 @@ bool DirNExporter::Export()
     string className = GetClassName();
     bool succ = false;
     napi_value classValue = nullptr;
-    tie(succ, classValue) = NClass::DefineClass(exports_.env_, className, DirNExporter::Constructor, std::move(props));
+    tie(succ, classValue) = NClass::GetInstance().DefineClass(exports_.env_, className, DirNExporter::Constructor, std::move(props));
     if (!succ) {
         UniError(EIO).ThrowErr(exports_.env_, "INNER BUG. Failed to define class Dirent");
         return false;
     }
 
-    succ = NClass::SaveClass(exports_.env_, className, classValue);
+    succ = NClass::GetInstance().SaveClass(exports_.env_, className, classValue);
     if (!succ) {
         UniError(EIO).ThrowErr(exports_.env_, "INNER BUG. Failed to save class Dirent");
         return false;
diff --git a/interfaces/kits/js/src/mod_fileio/class_dirent/dirent_n_exporter.cpp b/interfaces/kits/js/src/mod_fileio/class_dirent/dirent_n_exporter.cpp
index 29b78ca89dfc802e8130b98dd113c92424b9103d..9813a8c41902a4103e2f00579d15ba87181f36be 100644
--- a/interfaces/kits/js/src/mod_fileio/class_dirent/dirent_n_exporter.cpp
+++ b/interfaces/kits/js/src/mod_fileio/class_dirent/dirent_n_exporter.cpp
@@ -137,7 +137,7 @@ bool DirentNExporter::Export()
     string className = GetClassName();
     bool succ = false;
     napi_value classValue = nullptr;
-    tie(succ, classValue) = NClass::DefineClass(exports_.env_,
+    tie(succ, classValue) = NClass::GetInstance().DefineClass(exports_.env_,
                                                 className,
                                                 DirentNExporter::Constructor,
                                                 std::move(props));
@@ -146,7 +146,7 @@ bool DirentNExporter::Export()
         return false;
     }
 
-    succ = NClass::SaveClass(exports_.env_, className, classValue);
+    succ = NClass::GetInstance().SaveClass(exports_.env_, className, classValue);
     if (!succ) {
         UniError(EIO).ThrowErr(exports_.env_, "INNER BUG. Failed to save class Dirent");
         return false;
diff --git a/interfaces/kits/js/src/mod_fileio/class_file/file_n_exporter.cpp b/interfaces/kits/js/src/mod_fileio/class_file/file_n_exporter.cpp
index 4eeb63358e881794c575b497ff2618a236cf0553..d13a7867f2ffc7b3a91a1131fb491c8596ae672a 100644
--- a/interfaces/kits/js/src/mod_fileio/class_file/file_n_exporter.cpp
+++ b/interfaces/kits/js/src/mod_fileio/class_file/file_n_exporter.cpp
@@ -87,13 +87,13 @@ bool FileNExporter::Export()
     string className = GetClassName();
     bool succ = false;
     napi_value classValue = nullptr;
-    tie(succ, classValue) = NClass::DefineClass(exports_.env_, className,
+    tie(succ, classValue) = NClass::GetInstance().DefineClass(exports_.env_, className,
         FileNExporter::Constructor, move(props));
     if (!succ) {
         UniError(EIO, true).ThrowErr(exports_.env_);
         return false;
     }
-    succ = NClass::SaveClass(exports_.env_, className, classValue);
+    succ = NClass::GetInstance().SaveClass(exports_.env_, className, classValue);
     if (!succ) {
         UniError(EIO, true).ThrowErr(exports_.env_);
         return false;
diff --git a/interfaces/kits/js/src/mod_fileio/class_randomaccessfile/randomaccessfile_n_exporter.cpp b/interfaces/kits/js/src/mod_fileio/class_randomaccessfile/randomaccessfile_n_exporter.cpp
index 2078dea70e0bd79cfe3235b10d11c37fec8a4c7d..a6087ae8a909cd76200fcbceec872634de238f06 100644
--- a/interfaces/kits/js/src/mod_fileio/class_randomaccessfile/randomaccessfile_n_exporter.cpp
+++ b/interfaces/kits/js/src/mod_fileio/class_randomaccessfile/randomaccessfile_n_exporter.cpp
@@ -405,13 +405,13 @@ bool RandomAccessFileNExporter::Export()
     string className = GetClassName();
     bool succ = false;
     napi_value classValue = nullptr;
-    tie(succ, classValue) = NClass::DefineClass(exports_.env_, className,
+    tie(succ, classValue) = NClass::GetInstance().DefineClass(exports_.env_, className,
         RandomAccessFileNExporter::Constructor, move(props));
     if (!succ) {
         UniError(EIO).ThrowErr(exports_.env_, "INNER BUG. Failed to define class");
         return false;
     }
-    succ = NClass::SaveClass(exports_.env_, className, classValue);
+    succ = NClass::GetInstance().SaveClass(exports_.env_, className, classValue);
     if (!succ) {
         UniError(EIO).ThrowErr(exports_.env_, "INNER BUG. Failed to save class");
         return false;
diff --git a/interfaces/kits/js/src/mod_fileio/class_stat/stat_n_exporter.cpp b/interfaces/kits/js/src/mod_fileio/class_stat/stat_n_exporter.cpp
index 40c0ca18fe2db64a90095e06c124124224938b3b..4b08c93cbbc3f6fc2bb7bfa6743eee0b13af53ea 100644
--- a/interfaces/kits/js/src/mod_fileio/class_stat/stat_n_exporter.cpp
+++ b/interfaces/kits/js/src/mod_fileio/class_stat/stat_n_exporter.cpp
@@ -340,12 +340,12 @@ bool StatNExporter::Export()
     string className = GetClassName();
     bool succ = false;
     napi_value classValue = nullptr;
-    tie(succ, classValue) = NClass::DefineClass(exports_.env_, className, StatNExporter::Constructor, std::move(props));
+    tie(succ, classValue) = NClass::GetInstance().DefineClass(exports_.env_, className, StatNExporter::Constructor, std::move(props));
     if (!succ) {
         UniError(EIO).ThrowErr(exports_.env_, "INNER BUG. Failed to define class");
         return false;
     }
-    succ = NClass::SaveClass(exports_.env_, className, classValue);
+    succ = NClass::GetInstance().SaveClass(exports_.env_, className, classValue);
     if (!succ) {
         UniError(EIO).ThrowErr(exports_.env_, "INNER BUG. Failed to save class");
         return false;
diff --git a/interfaces/kits/js/src/mod_fileio/class_stat_v9/stat_n_exporter_v9.cpp b/interfaces/kits/js/src/mod_fileio/class_stat_v9/stat_n_exporter_v9.cpp
index fb2768f698b00b72d525ed2108c7fa2e1b354d1e..6d2d4fd2307bb9f8f412216bdc5cff4e3c915c61 100644
--- a/interfaces/kits/js/src/mod_fileio/class_stat_v9/stat_n_exporter_v9.cpp
+++ b/interfaces/kits/js/src/mod_fileio/class_stat_v9/stat_n_exporter_v9.cpp
@@ -275,13 +275,13 @@ bool StatNExporterV9::Export()
     string className = GetClassName();
     bool succ = false;
     napi_value classValue = nullptr;
-    tie(succ, classValue) = NClass::DefineClass(exports_.env_, className, StatNExporterV9::Constructor,
+    tie(succ, classValue) = NClass::GetInstance().DefineClass(exports_.env_, className, StatNExporterV9::Constructor,
         std::move(props));
     if (!succ) {
         UniError(EIO, true).ThrowErr(exports_.env_);
         return false;
     }
-    succ = NClass::SaveClass(exports_.env_, className, classValue);
+    succ = NClass::GetInstance().SaveClass(exports_.env_, className, classValue);
     if (!succ) {
         UniError(EIO, true).ThrowErr(exports_.env_);
         return false;
diff --git a/interfaces/kits/js/src/mod_fileio/class_stream/stream_n_exporter.cpp b/interfaces/kits/js/src/mod_fileio/class_stream/stream_n_exporter.cpp
index f9d6960b858f73d554ce6bfcd907950f535b1172..20dfb714d559356287429994df01aceefc429fed 100644
--- a/interfaces/kits/js/src/mod_fileio/class_stream/stream_n_exporter.cpp
+++ b/interfaces/kits/js/src/mod_fileio/class_stream/stream_n_exporter.cpp
@@ -371,12 +371,12 @@ bool StreamNExporter::Export()
     string className = GetClassName();
     bool succ = false;
     napi_value cls = nullptr;
-    tie(succ, cls) = NClass::DefineClass(exports_.env_, className, StreamNExporter::Constructor, move(props));
+    tie(succ, cls) = NClass::GetInstance().DefineClass(exports_.env_, className, StreamNExporter::Constructor, move(props));
     if (!succ) {
         UniError(EIO).ThrowErr(exports_.env_, "INNER BUG. Failed to define class");
         return false;
     }
-    succ = NClass::SaveClass(exports_.env_, className, cls);
+    succ = NClass::GetInstance().SaveClass(exports_.env_, className, cls);
     if (!succ) {
         UniError(EIO).ThrowErr(exports_.env_, "INNER BUG. Failed to save class");
         return false;
diff --git a/interfaces/kits/js/src/mod_fileio/class_watcher/watcher_n_exporter.cpp b/interfaces/kits/js/src/mod_fileio/class_watcher/watcher_n_exporter.cpp
index 2947b10cb50e5d108cb3d81e27eb5ee9e53f8274..1a262bf02f6b77a5d37e763b0be9b6990e76bc6e 100644
--- a/interfaces/kits/js/src/mod_fileio/class_watcher/watcher_n_exporter.cpp
+++ b/interfaces/kits/js/src/mod_fileio/class_watcher/watcher_n_exporter.cpp
@@ -113,7 +113,7 @@ bool WatcherNExporter::Export()
     };
 
     string className = GetClassName();
-    auto [resDefineClass, classValue] = NClass::DefineClass(exports_.env_,
+    auto [resDefineClass, classValue] = NClass::GetInstance().DefineClass(exports_.env_,
                                                             className,
                                                             WatcherNExporter::Constructor,
                                                             std::move(props));
@@ -122,7 +122,7 @@ bool WatcherNExporter::Export()
         return false;
     }
 
-    bool succ = NClass::SaveClass(exports_.env_, className, classValue);
+    bool succ = NClass::GetInstance().SaveClass(exports_.env_, className, classValue);
     if (!succ) {
         UniError(EIO).ThrowErr(exports_.env_, "INNER BUG. Failed to save class");
         return false;
diff --git a/interfaces/kits/js/src/mod_fs/class_file/file_n_exporter.cpp b/interfaces/kits/js/src/mod_fs/class_file/file_n_exporter.cpp
index 4ab935a2418ce1acc5a6889aaa42380bb5d5f758..39b89da800bd42f5a061ca267b8b6a2399196b6a 100644
--- a/interfaces/kits/js/src/mod_fs/class_file/file_n_exporter.cpp
+++ b/interfaces/kits/js/src/mod_fs/class_file/file_n_exporter.cpp
@@ -216,14 +216,14 @@ bool FileNExporter::Export()
     string className = GetClassName();
     bool succ = false;
     napi_value classValue = nullptr;
-    tie(succ, classValue) = NClass::DefineClass(exports_.env_, className,
+    tie(succ, classValue) = NClass::GetInstance().DefineClass(exports_.env_, className,
         FileNExporter::Constructor, move(props));
     if (!succ) {
         HILOGE("Define class exceptions");
         NError(EIO).ThrowErr(exports_.env_);
         return false;
     }
-    succ = NClass::SaveClass(exports_.env_, className, classValue);
+    succ = NClass::GetInstance().SaveClass(exports_.env_, className, classValue);
     if (!succ) {
         HILOGE("Save class exceptions");
         NError(EIO).ThrowErr(exports_.env_);
diff --git a/interfaces/kits/js/src/mod_fs/class_stat/stat_n_exporter.cpp b/interfaces/kits/js/src/mod_fs/class_stat/stat_n_exporter.cpp
index 0b2baa572bc9466f4a4c6c997dd1f080bf576537..56341ca6f09a85e6d9bc9337257c1a2e6dd8b3a5 100644
--- a/interfaces/kits/js/src/mod_fs/class_stat/stat_n_exporter.cpp
+++ b/interfaces/kits/js/src/mod_fs/class_stat/stat_n_exporter.cpp
@@ -267,14 +267,14 @@ bool StatNExporter::Export()
     string className = GetClassName();
     bool succ = false;
     napi_value classValue = nullptr;
-    tie(succ, classValue) = NClass::DefineClass(exports_.env_, className, StatNExporter::Constructor,
+    tie(succ, classValue) = NClass::GetInstance().DefineClass(exports_.env_, className, StatNExporter::Constructor,
         std::move(props));
     if (!succ) {
         HILOGE("Failed to define class");
         NError(EIO).ThrowErr(exports_.env_);
         return false;
     }
-    succ = NClass::SaveClass(exports_.env_, className, classValue);
+    succ = NClass::GetInstance().SaveClass(exports_.env_, className, classValue);
     if (!succ) {
         HILOGE("Failed to save class");
         NError(EIO).ThrowErr(exports_.env_);
diff --git a/interfaces/kits/js/src/mod_fs/class_stream/stream_n_exporter.cpp b/interfaces/kits/js/src/mod_fs/class_stream/stream_n_exporter.cpp
index 5bfd00d7a1f34fe5639b9ac55be2b7119bd787a9..a9c7d16017c3490e128d0a4de0a15dad6bfbed52 100644
--- a/interfaces/kits/js/src/mod_fs/class_stream/stream_n_exporter.cpp
+++ b/interfaces/kits/js/src/mod_fs/class_stream/stream_n_exporter.cpp
@@ -354,13 +354,13 @@ bool StreamNExporter::Export()
     string className = GetClassName();
     bool succ = false;
     napi_value cls = nullptr;
-    tie(succ, cls) = NClass::DefineClass(exports_.env_, className, StreamNExporter::Constructor, move(props));
+    tie(succ, cls) = NClass::GetInstance().DefineClass(exports_.env_, className, StreamNExporter::Constructor, move(props));
     if (!succ) {
         HILOGE("INNER BUG. Failed to define class");
         NError(EIO).ThrowErr(exports_.env_);
         return false;
     }
-    succ = NClass::SaveClass(exports_.env_, className, cls);
+    succ = NClass::GetInstance().SaveClass(exports_.env_, className, cls);
     if (!succ) {
         HILOGE("INNER BUG. Failed to save class");
         NError(EIO).ThrowErr(exports_.env_);
diff --git a/interfaces/kits/js/src/mod_fs/class_watcher/watcher_n_exporter.cpp b/interfaces/kits/js/src/mod_fs/class_watcher/watcher_n_exporter.cpp
index abc57862652955bd52a9766f2c9cf4a797dbaa8e..787f711fe76273bb81980dc6205fe11836bd8a5e 100644
--- a/interfaces/kits/js/src/mod_fs/class_watcher/watcher_n_exporter.cpp
+++ b/interfaces/kits/js/src/mod_fs/class_watcher/watcher_n_exporter.cpp
@@ -192,13 +192,13 @@ bool WatcherNExporter::Export()
 
     string className = GetClassName();
     auto [resDefineClass, classValue] =
-        NClass::DefineClass(exports_.env_, className, WatcherNExporter::Constructor, std::move(props));
+        NClass::GetInstance().DefineClass(exports_.env_, className, WatcherNExporter::Constructor, std::move(props));
     if (!resDefineClass) {
         NError(EIO).ThrowErr(exports_.env_);
         return false;
     }
 
-    bool succ = NClass::SaveClass(exports_.env_, className, classValue);
+    bool succ = NClass::GetInstance().SaveClass(exports_.env_, className, classValue);
     if (!succ) {
         NError(EIO).ThrowErr(exports_.env_);
         return false;
diff --git a/utils/filemgmt_libn/src/n_class.cpp b/utils/filemgmt_libn/src/n_class.cpp
index b8a76bd68d3675bdf72c321ebd02140394365085..af0e75301be7e0a8fe1a24484493854f10be7c4b 100644
--- a/utils/filemgmt_libn/src/n_class.cpp
+++ b/utils/filemgmt_libn/src/n_class.cpp
@@ -27,7 +27,7 @@ NClass &NClass::GetInstance()
     return nClass;
 }
 
-tuple<bool, napi_value> NClass::DefineClass(napi_env env,
+tuple<bool, napi_value> NClass::GetInstance().DefineClass(napi_env env,
                                             string className,
                                             napi_callback constructor,
                                             vector<napi_property_descriptor> &&properties)
@@ -42,7 +42,7 @@ tuple<bool, napi_value> NClass::DefineClass(napi_env env,
     return {stat == napi_ok, classVal};
 }
 
-bool NClass::SaveClass(napi_env env, string className, napi_value exClass)
+bool NClass::GetInstance().SaveClass(napi_env env, string className, napi_value exClass)
 {
     NClass &nClass = NClass::GetInstance();
     lock_guard<std::mutex>(nClass.exClassMapLock);