diff --git a/container/garray/garray_normal_t.go b/container/garray/garray_normal_t.go
index fa0ce054013..98a8ec7b81d 100644
--- a/container/garray/garray_normal_t.go
+++ b/container/garray/garray_normal_t.go
@@ -749,7 +749,9 @@ func (a *TArray[T]) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-// Note that do not use pointer as its receiver here.
+// DO NOT change this receiver to pointer type, as the TArray can be used as a var defined variable, like:
+// var a TArray[int]
+// Please refer to corresponding tests for more details.
 func (a TArray[T]) MarshalJSON() ([]byte, error) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
diff --git a/container/garray/garray_sorted_t.go b/container/garray/garray_sorted_t.go
index 25d62f2ff0e..981785f9b5a 100644
--- a/container/garray/garray_sorted_t.go
+++ b/container/garray/garray_sorted_t.go
@@ -46,7 +46,7 @@ func NewSortedTArray[T comparable](comparator func(a, b T) int, safe ...bool) *S
 	return NewSortedTArraySize(0, comparator, safe...)
 }
 
-// NewSortedTArraySize create and returns an sorted array with given size and cap.
+// NewSortedTArraySize create and returns a sorted array with given size and cap.
 // The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewSortedTArraySize[T comparable](cap int, comparator func(a, b T) int, safe ...bool) *SortedTArray[T] {
@@ -718,7 +718,9 @@ func (a *SortedTArray[T]) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
-// Note that do not use pointer as its receiver here.
+// DO NOT change this receiver to pointer type, as the TArray can be used as a var defined variable, like:
+// var a SortedTArray[int]
+// Please refer to corresponding tests for more details.
 func (a SortedTArray[T]) MarshalJSON() ([]byte, error) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
diff --git a/container/gmap/gmap_hash_k_v_map.go b/container/gmap/gmap_hash_k_v_map.go
index 6d65d59e9ee..c8f6372e09e 100644
--- a/container/gmap/gmap_hash_k_v_map.go
+++ b/container/gmap/gmap_hash_k_v_map.go
@@ -22,8 +22,11 @@ type NilChecker[V any] func(V) bool
 
 // KVMap wraps map type `map[K]V` and provides more map features.
 type KVMap[K comparable, V any] struct {
-	mu         rwmutex.RWMutex
-	data       map[K]V
+	mu   rwmutex.RWMutex
+	data map[K]V
+
+	// nilChecker is the custom nil checker function.
+	// It uses empty.IsNil if it's nil.
 	nilChecker NilChecker[V]
 }
 
@@ -58,15 +61,15 @@ func NewKVMapFrom[K comparable, V any](data map[K]V, safe ...bool) *KVMap[K, V]
 // The parameter `safe` is used to specify whether to use the map in concurrent-safety mode, which is false by default.
 func NewKVMapWithCheckerFrom[K comparable, V any](data map[K]V, checker NilChecker[V], safe ...bool) *KVMap[K, V] {
 	m := NewKVMapFrom[K, V](data, safe...)
-	m.RegisterNilChecker(checker)
+	m.SetNilChecker(checker)
 	return m
 }
 
-// RegisterNilChecker registers a custom nil checker function for the map values.
+// SetNilChecker registers a custom nil checker function for the map values.
 // This function is used to determine if a value should be considered as nil.
 // The nil checker function takes a value of type V and returns a boolean indicating
 // whether the value should be treated as nil.
-func (m *KVMap[K, V]) RegisterNilChecker(nilChecker NilChecker[V]) {
+func (m *KVMap[K, V]) SetNilChecker(nilChecker NilChecker[V]) {
 	m.mu.Lock()
 	defer m.mu.Unlock()
 	m.nilChecker = nilChecker
@@ -74,12 +77,12 @@ func (m *KVMap[K, V]) RegisterNilChecker(nilChecker NilChecker[V]) {
 
 // isNil checks whether the given value is nil.
 // It first checks if a custom nil checker function is registered and uses it if available,
-// otherwise it performs a standard nil check using any(v) == nil.
+// otherwise it falls back to the default empty.IsNil function.
 func (m *KVMap[K, V]) isNil(v V) bool {
 	if m.nilChecker != nil {
 		return m.nilChecker(v)
 	}
-	return any(v) == nil
+	return empty.IsNil(v)
 }
 
 // Iterator iterates the hash map readonly with custom callback function `f`.
@@ -242,11 +245,12 @@ func (m *KVMap[K, V]) Pops(size int) map[K]V {
 	return newMap
 }
 
-// doSetWithLockCheck checks whether value of the key exists with mutex.Lock,
-// if not exists, set value to the map with given `key`,
-// or else just return the existing value.
+// doSetWithLockCheck sets value with given `value` if it does not exist,
+// and then returns this value and whether it exists.
+//
+// It is a helper function for GetOrSet* functions.
 //
-// It returns value with given `key`.
+// Note that, it does not add the value to the map if the given `value` is nil.
 func (m *KVMap[K, V]) doSetWithLockCheck(key K, value V) (val V, ok bool) {
 	m.mu.Lock()
 	defer m.mu.Unlock()
@@ -274,6 +278,8 @@ func (m *KVMap[K, V]) GetOrSet(key K, value V) V {
 // GetOrSetFunc returns the value by key,
 // or sets value with returned value of callback function `f` if it does not exist
 // and then returns this value.
+//
+// Note that, it does not add the value to the map if the returned value of `f` is nil.
 func (m *KVMap[K, V]) GetOrSetFunc(key K, f func() V) V {
 	v, _ := m.doSetWithLockCheck(key, f())
 	return v
@@ -285,6 +291,8 @@ func (m *KVMap[K, V]) GetOrSetFunc(key K, f func() V) V {
 //
 // GetOrSetFuncLock differs with GetOrSetFunc function is that it executes function `f`
 // with mutex.Lock of the hash map.
+//
+// Note that, it does not add the value to the map if the returned value of `f` is nil.
 func (m *KVMap[K, V]) GetOrSetFuncLock(key K, f func() V) V {
 	m.mu.Lock()
 	defer m.mu.Unlock()
@@ -524,6 +532,9 @@ func (m *KVMap[K, V]) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
+// DO NOT change this receiver to pointer type, as the KVMap can be used as a var defined variable, like:
+// var m gmap.KVMap[int, string]
+// Please refer to corresponding tests for more details.
 func (m KVMap[K, V]) MarshalJSON() ([]byte, error) {
 	return json.Marshal(gconv.Map(m.Map()))
 }
diff --git a/container/gmap/gmap_list_k_v_map.go b/container/gmap/gmap_list_k_v_map.go
index 6b37ed57c31..61d99f0b909 100644
--- a/container/gmap/gmap_list_k_v_map.go
+++ b/container/gmap/gmap_list_k_v_map.go
@@ -56,7 +56,7 @@ func NewListKVMap[K comparable, V any](safe ...bool) *ListKVMap[K, V] {
 // which is false by default.
 func NewListKVMapWithChecker[K comparable, V any](checker NilChecker[V], safe ...bool) *ListKVMap[K, V] {
 	m := NewListKVMap[K, V](safe...)
-	m.RegisterNilChecker(checker)
+	m.SetNilChecker(checker)
 	return m
 }
 
@@ -81,11 +81,11 @@ func NewListKVMapWithCheckerFrom[K comparable, V any](data map[K]V, nilChecker N
 	return m
 }
 
-// RegisterNilChecker registers a custom nil checker function for the map values.
+// SetNilChecker registers a custom nil checker function for the map values.
 // This function is used to determine if a value should be considered as nil.
 // The nil checker function takes a value of type V and returns a boolean indicating
 // whether the value should be treated as nil.
-func (m *ListKVMap[K, V]) RegisterNilChecker(nilChecker NilChecker[V]) {
+func (m *ListKVMap[K, V]) SetNilChecker(nilChecker NilChecker[V]) {
 	m.mu.Lock()
 	defer m.mu.Unlock()
 	m.nilChecker = nilChecker
@@ -93,12 +93,12 @@ func (m *ListKVMap[K, V]) RegisterNilChecker(nilChecker NilChecker[V]) {
 
 // isNil checks whether the given value is nil.
 // It first checks if a custom nil checker function is registered and uses it if available,
-// otherwise it performs a standard nil check using any(v) == nil.
+// otherwise it falls back to the default empty.IsNil function.
 func (m *ListKVMap[K, V]) isNil(v V) bool {
 	if m.nilChecker != nil {
 		return m.nilChecker(v)
 	}
-	return any(v) == nil
+	return empty.IsNil(v)
 }
 
 // Iterator is alias of IteratorAsc.
@@ -402,6 +402,8 @@ func (m *ListKVMap[K, V]) GetVarOrSetFuncLock(key K, f func() V) *gvar.Var {
 
 // SetIfNotExist sets `value` to the map if the `key` does not exist, and then returns true.
 // It returns false if `key` exists, and `value` would be ignored.
+//
+// Note that it does not add the value to the map if `value` is nil.
 func (m *ListKVMap[K, V]) SetIfNotExist(key K, value V) bool {
 	m.mu.Lock()
 	defer m.mu.Unlock()
@@ -421,6 +423,8 @@ func (m *ListKVMap[K, V]) SetIfNotExist(key K, value V) bool {
 
 // SetIfNotExistFunc sets value with return value of callback function `f`, and then returns true.
 // It returns false if `key` exists, and `value` would be ignored.
+//
+// Note that, it does not add the value to the map if the returned value of `f` is nil.
 func (m *ListKVMap[K, V]) SetIfNotExistFunc(key K, f func() V) bool {
 	m.mu.Lock()
 	defer m.mu.Unlock()
@@ -444,6 +448,8 @@ func (m *ListKVMap[K, V]) SetIfNotExistFunc(key K, f func() V) bool {
 //
 // SetIfNotExistFuncLock differs with SetIfNotExistFunc function is that
 // it executes function `f` with mutex.Lock of the map.
+//
+// Note that, it does not add the value to the map if the returned value of `f` is nil.
 func (m *ListKVMap[K, V]) SetIfNotExistFuncLock(key K, f func() V) bool {
 	m.mu.Lock()
 	defer m.mu.Unlock()
@@ -609,6 +615,9 @@ func (m *ListKVMap[K, V]) String() string {
 }
 
 // MarshalJSON implements the interface MarshalJSON for json.Marshal.
+// DO NOT change this receiver to pointer type, as the ListKVMap can be used as a var defined variable, like:
+// var m gmap.ListKVMap[string]string
+// Please refer to corresponding tests for more details.
 func (m ListKVMap[K, V]) MarshalJSON() (jsonBytes []byte, err error) {
 	if m.data == nil {
 		return []byte("{}"), nil
diff --git a/container/gmap/gmap_z_unit_k_v_map_test.go b/container/gmap/gmap_z_unit_k_v_map_test.go
index 4bd9779596f..8d95f4fa8f4 100644
--- a/container/gmap/gmap_z_unit_k_v_map_test.go
+++ b/container/gmap/gmap_z_unit_k_v_map_test.go
@@ -774,6 +774,13 @@ func Test_KVMap_MarshalJSON(t *testing.T) {
 		t.Assert(data["a"], 1)
 		t.Assert(data["b"], 2)
 	})
+	gtest.C(t, func(t *gtest.T) {
+		var m gmap.KVMap[int, int]
+		m.Set(1, 10)
+		b, err := json.Marshal(m)
+		t.AssertNil(err)
+		t.Assert(string(b), `{"1":10}`)
+	})
 }
 
 func Test_KVMap_UnmarshalJSON(t *testing.T) {
@@ -1647,9 +1654,10 @@ func Test_KVMap_TypedNil(t *testing.T) {
 				return nil
 			})
 		}
-		t.Assert(m1.Size(), 10)
+		t.Assert(m1.Size(), 5)
+
 		m2 := gmap.NewKVMap[int, *Student](true)
-		m2.RegisterNilChecker(func(student *Student) bool {
+		m2.SetNilChecker(func(student *Student) bool {
 			return student == nil
 		})
 		for i := 0; i < 10; i++ {
@@ -1679,7 +1687,8 @@ func Test_NewKVMapWithChecker_TypedNil(t *testing.T) {
 				return nil
 			})
 		}
-		t.Assert(m1.Size(), 10)
+		t.Assert(m1.Size(), 5)
+
 		m2 := gmap.NewKVMapWithChecker[int, *Student](func(student *Student) bool {
 			return student == nil
 		}, true)
diff --git a/container/gmap/gmap_z_unit_list_k_v_map_race_test.go b/container/gmap/gmap_z_unit_list_k_v_map_race_test.go
index d3156866201..5c5e869f159 100644
--- a/container/gmap/gmap_z_unit_list_k_v_map_race_test.go
+++ b/container/gmap/gmap_z_unit_list_k_v_map_race_test.go
@@ -183,77 +183,6 @@ func Test_ListKVMap_SetIfNotExistFuncLock_MultipleKeys(t *testing.T) {
 	})
 }
 
-// Test_ListKVMap_GetOrSetFuncLock_NilValue tests that nil values are handled correctly.
-func Test_ListKVMap_GetOrSetFuncLock_NilValue(t *testing.T) {
-	gtest.C(t, func(t *gtest.T) {
-		m := gmap.NewListKVMap[string, *int](true)
-		key := "nilKey"
-		callCount := int32(0)
-
-		var wg sync.WaitGroup
-		goroutines := 50
-		wg.Add(goroutines)
-
-		for i := 0; i < goroutines; i++ {
-			go func() {
-				defer wg.Done()
-				m.GetOrSetFuncLock(key, func() *int {
-					atomic.AddInt32(&callCount, 1)
-					return nil
-				})
-			}()
-		}
-
-		wg.Wait()
-
-		// Callback should be called once
-		t.Assert(atomic.LoadInt32(&callCount), 1)
-		// Typed nil pointer (*int)(nil) is stored because any(value) != nil for typed nil
-		// This is a Go language feature: typed nil is not the same as interface nil
-		t.Assert(m.Contains(key), true)
-		t.Assert(m.Get(key), (*int)(nil))
-		t.Assert(m.Size(), 1)
-	})
-}
-
-// Test_ListKVMap_SetIfNotExistFuncLock_NilValue tests that nil values are handled correctly.
-func Test_ListKVMap_SetIfNotExistFuncLock_NilValue(t *testing.T) {
-	gtest.C(t, func(t *gtest.T) {
-		m := gmap.NewListKVMap[string, *string](true)
-		key := "nilKey"
-		callCount := int32(0)
-		successCount := int32(0)
-
-		var wg sync.WaitGroup
-		goroutines := 50
-		wg.Add(goroutines)
-
-		for i := 0; i < goroutines; i++ {
-			go func() {
-				defer wg.Done()
-				success := m.SetIfNotExistFuncLock(key, func() *string {
-					atomic.AddInt32(&callCount, 1)
-					return nil
-				})
-				if success {
-					atomic.AddInt32(&successCount, 1)
-				}
-			}()
-		}
-
-		wg.Wait()
-
-		// Callback should be called once
-		t.Assert(atomic.LoadInt32(&callCount), 1)
-		// Should report success once
-		t.Assert(atomic.LoadInt32(&successCount), 1)
-		// Typed nil pointer (*string)(nil) is stored because any(value) != nil for typed nil
-		t.Assert(m.Contains(key), true)
-		t.Assert(m.Get(key), (*string)(nil))
-		t.Assert(m.Size(), 1)
-	})
-}
-
 // Test_ListKVMap_GetOrSetFuncLock_ExistingKey tests behavior when key already exists.
 func Test_ListKVMap_GetOrSetFuncLock_ExistingKey(t *testing.T) {
 	gtest.C(t, func(t *gtest.T) {
diff --git a/container/gmap/gmap_z_unit_list_k_v_map_test.go b/container/gmap/gmap_z_unit_list_k_v_map_test.go
index 5b9db095f90..63e6fbc46d9 100644
--- a/container/gmap/gmap_z_unit_list_k_v_map_test.go
+++ b/container/gmap/gmap_z_unit_list_k_v_map_test.go
@@ -1159,6 +1159,13 @@ func Test_ListKVMap_MarshalJSON_Error(t *testing.T) {
 		t.AssertNil(err)
 		t.Assert(string(b), `{"a":"1"}`)
 	})
+	gtest.C(t, func(t *gtest.T) {
+		var m gmap.ListKVMap[int, int]
+		m.Set(1, 10)
+		b, err := json.Marshal(m)
+		t.AssertNil(err)
+		t.Assert(string(b), `{"1":10}`)
+	})
 }
 
 // Test empty map operations
@@ -1358,9 +1365,10 @@ func Test_ListKVMap_TypedNil(t *testing.T) {
 				return nil
 			})
 		}
-		t.Assert(m1.Size(), 10)
+		t.Assert(m1.Size(), 5)
+
 		m2 := gmap.NewListKVMap[int, *Student](true)
-		m2.RegisterNilChecker(func(student *Student) bool {
+		m2.SetNilChecker(func(student *Student) bool {
 			return student == nil
 		})
 		for i := 0; i < 10; i++ {
@@ -1390,7 +1398,8 @@ func Test_NewListKVMapWithChecker_TypedNil(t *testing.T) {
 				return nil
 			})
 		}
-		t.Assert(m1.Size(), 10)
+		t.Assert(m1.Size(), 5)
+
 		m2 := gmap.NewListKVMapWithChecker[int, *Student](func(student *Student) bool {
 			return student == nil
 		}, true)
diff --git a/container/gset/gset_t_set.go b/container/gset/gset_t_set.go
index 02ffbf6cd0f..15962e57ecb 100644
--- a/container/gset/gset_t_set.go
+++ b/container/gset/gset_t_set.go
@@ -9,6 +9,7 @@ package gset
 import (
 	"bytes"
 
+	"github.com/gogf/gf/v2/internal/empty"
 	"github.com/gogf/gf/v2/internal/json"
 	"github.com/gogf/gf/v2/internal/rwmutex"
 	"github.com/gogf/gf/v2/text/gstr"
@@ -39,7 +40,7 @@ func NewTSet[T comparable](safe ...bool) *TSet[T] {
 // The parameter `safe` is used to specify whether using set in concurrent-safety mode.
 func NewTSetWithChecker[T comparable](checker NilChecker[T], safe ...bool) *TSet[T] {
 	s := NewTSet[T](safe...)
-	s.RegisterNilChecker(checker)
+	s.SetNilChecker(checker)
 	return s
 }
 
@@ -66,11 +67,11 @@ func NewTSetWithCheckerFrom[T comparable](items []T, checker NilChecker[T], safe
 	return set
 }
 
-// RegisterNilChecker registers a custom nil checker function for the set elements.
+// SetNilChecker registers a custom nil checker function for the set elements.
 // This function is used to determine if an element should be considered as nil.
 // The nil checker function takes an element of type T and returns a boolean indicating
 // whether the element should be treated as nil.
-func (set *TSet[T]) RegisterNilChecker(nilChecker NilChecker[T]) {
+func (set *TSet[T]) SetNilChecker(nilChecker NilChecker[T]) {
 	set.mu.Lock()
 	defer set.mu.Unlock()
 	set.nilChecker = nilChecker
@@ -78,12 +79,12 @@ func (set *TSet[T]) RegisterNilChecker(nilChecker NilChecker[T]) {
 
 // isNil checks whether the given value is nil.
 // It first checks if a custom nil checker function is registered and uses it if available,
-// otherwise it performs a standard nil check using any(v) == nil.
+// otherwise it falls back to the default empty.IsNil function.
 func (set *TSet[T]) isNil(v T) bool {
 	if set.nilChecker != nil {
 		return set.nilChecker(v)
 	}
-	return any(v) == nil
+	return empty.IsNil(v)
 }
 
 // Iterator iterates the set readonly with given callback function `f`,
@@ -109,7 +110,7 @@ func (set *TSet[T]) Add(items ...T) {
 }
 
 // AddIfNotExist checks whether item exists in the set,
-// it adds the item to set and returns true if it does not exists in the set,
+// it adds the item to set and returns true if it does not exist in the set,
 // or else it does nothing and returns false.
 //
 // Note that, if `item` is nil, it does nothing and returns false.
diff --git a/container/gset/gset_z_unit_t_set_test.go b/container/gset/gset_z_unit_t_set_test.go
index 10558a707ad..66cfb326bc5 100644
--- a/container/gset/gset_z_unit_t_set_test.go
+++ b/container/gset/gset_z_unit_t_set_test.go
@@ -601,10 +601,10 @@ func Test_TSet_TypedNil(t *testing.T) {
 		set := gset.NewTSet[*Student](true)
 		var s *Student = nil
 		exist := set.AddIfNotExist(s)
-		t.Assert(exist, true)
+		t.Assert(exist, false)
 
 		set2 := gset.NewTSet[*Student](true)
-		set2.RegisterNilChecker(func(student *Student) bool {
+		set2.SetNilChecker(func(student *Student) bool {
 			return student == nil
 		})
 		exist2 := set2.AddIfNotExist(s)
@@ -621,7 +621,7 @@ func Test_NewTSetWithChecker_TypedNil(t *testing.T) {
 		set := gset.NewTSet[*Student](true)
 		var s *Student = nil
 		exist := set.AddIfNotExist(s)
-		t.Assert(exist, true)
+		t.Assert(exist, false)
 
 		set2 := gset.NewTSetWithChecker[*Student](func(student *Student) bool {
 			return student == nil
diff --git a/container/gtree/gtree_k_v_avltree.go b/container/gtree/gtree_k_v_avltree.go
index 6613647512c..b0fe2d293a4 100644
--- a/container/gtree/gtree_k_v_avltree.go
+++ b/container/gtree/gtree_k_v_avltree.go
@@ -12,6 +12,7 @@ import (
 	"github.com/emirpasic/gods/v2/trees/avltree"
 
 	"github.com/gogf/gf/v2/container/gvar"
+	"github.com/gogf/gf/v2/internal/empty"
 	"github.com/gogf/gf/v2/internal/json"
 	"github.com/gogf/gf/v2/internal/rwmutex"
 	"github.com/gogf/gf/v2/text/gstr"
@@ -52,7 +53,7 @@ func NewAVLKVTree[K comparable, V any](comparator func(v1, v2 K) int, safe ...bo
 // The parameter `checker` is used to specify whether the given value is nil.
 func NewAVLKVTreeWithChecker[K comparable, V any](comparator func(v1, v2 K) int, checker NilChecker[V], safe ...bool) *AVLKVTree[K, V] {
 	t := NewAVLKVTree[K, V](comparator, safe...)
-	t.RegisterNilChecker(checker)
+	t.SetNilChecker(checker)
 	return t
 }
 
@@ -78,11 +79,11 @@ func NewAVLKVTreeWithCheckerFrom[K comparable, V any](comparator func(v1, v2 K)
 	return tree
 }
 
-// RegisterNilChecker registers a custom nil checker function for the map values.
+// SetNilChecker registers a custom nil checker function for the map values.
 // This function is used to determine if a value should be considered as nil.
 // The nil checker function takes a value of type V and returns a boolean indicating
 // whether the value should be treated as nil.
-func (tree *AVLKVTree[K, V]) RegisterNilChecker(nilChecker NilChecker[V]) {
+func (tree *AVLKVTree[K, V]) SetNilChecker(nilChecker NilChecker[V]) {
 	tree.mu.Lock()
 	defer tree.mu.Unlock()
 	tree.nilChecker = nilChecker
@@ -90,12 +91,12 @@ func (tree *AVLKVTree[K, V]) RegisterNilChecker(nilChecker NilChecker[V]) {
 
 // isNil checks whether the given value is nil.
 // It first checks if a custom nil checker function is registered and uses it if available,
-// otherwise it performs a standard nil check using any(v) == nil.
-func (tree *AVLKVTree[K, V]) isNil(value V) bool {
+// otherwise it falls back to the default empty.IsNil function.
+func (tree *AVLKVTree[K, V]) isNil(v V) bool {
 	if tree.nilChecker != nil {
-		return tree.nilChecker(value)
+		return tree.nilChecker(v)
 	}
-	return any(value) == nil
+	return empty.IsNil(v)
 }
 
 // Clone clones and returns a new tree from current tree.
diff --git a/container/gtree/gtree_k_v_btree.go b/container/gtree/gtree_k_v_btree.go
index 2adcede1b9b..7586622aebb 100644
--- a/container/gtree/gtree_k_v_btree.go
+++ b/container/gtree/gtree_k_v_btree.go
@@ -12,6 +12,7 @@ import (
 	"github.com/emirpasic/gods/v2/trees/btree"
 
 	"github.com/gogf/gf/v2/container/gvar"
+	"github.com/gogf/gf/v2/internal/empty"
 	"github.com/gogf/gf/v2/internal/json"
 	"github.com/gogf/gf/v2/internal/rwmutex"
 	"github.com/gogf/gf/v2/text/gstr"
@@ -51,7 +52,7 @@ func NewBKVTree[K comparable, V any](m int, comparator func(v1, v2 K) int, safe
 // The parameter `checker` is used to specify whether the given value is nil.
 func NewBKVTreeWithChecker[K comparable, V any](m int, comparator func(v1, v2 K) int, checker NilChecker[V], safe ...bool) *BKVTree[K, V] {
 	t := NewBKVTree[K, V](m, comparator, safe...)
-	t.RegisterNilChecker(checker)
+	t.SetNilChecker(checker)
 	return t
 }
 
@@ -77,11 +78,11 @@ func NewBKVTreeWithCheckerFrom[K comparable, V any](m int, comparator func(v1, v
 	return tree
 }
 
-// RegisterNilChecker registers a custom nil checker function for the map values.
+// SetNilChecker registers a custom nil checker function for the map values.
 // This function is used to determine if a value should be considered as nil.
 // The nil checker function takes a value of type V and returns a boolean indicating
 // whether the value should be treated as nil.
-func (tree *BKVTree[K, V]) RegisterNilChecker(nilChecker NilChecker[V]) {
+func (tree *BKVTree[K, V]) SetNilChecker(nilChecker NilChecker[V]) {
 	tree.mu.Lock()
 	defer tree.mu.Unlock()
 	tree.nilChecker = nilChecker
@@ -89,12 +90,12 @@ func (tree *BKVTree[K, V]) RegisterNilChecker(nilChecker NilChecker[V]) {
 
 // isNil checks whether the given value is nil.
 // It first checks if a custom nil checker function is registered and uses it if available,
-// otherwise it performs a standard nil check using any(v) == nil.
-func (tree *BKVTree[K, V]) isNil(value V) bool {
+// otherwise it falls back to the default empty.IsNil function.
+func (tree *BKVTree[K, V]) isNil(v V) bool {
 	if tree.nilChecker != nil {
-		return tree.nilChecker(value)
+		return tree.nilChecker(v)
 	}
-	return any(value) == nil
+	return empty.IsNil(v)
 }
 
 // Clone clones and returns a new tree from current tree.
diff --git a/container/gtree/gtree_k_v_redblacktree.go b/container/gtree/gtree_k_v_redblacktree.go
index 47585716a98..49936d73bf6 100644
--- a/container/gtree/gtree_k_v_redblacktree.go
+++ b/container/gtree/gtree_k_v_redblacktree.go
@@ -12,6 +12,7 @@ import (
 	"github.com/emirpasic/gods/v2/trees/redblacktree"
 
 	"github.com/gogf/gf/v2/container/gvar"
+	"github.com/gogf/gf/v2/internal/empty"
 	"github.com/gogf/gf/v2/internal/json"
 	"github.com/gogf/gf/v2/internal/rwmutex"
 	"github.com/gogf/gf/v2/text/gstr"
@@ -47,7 +48,7 @@ func NewRedBlackKVTree[K comparable, V any](comparator func(v1, v2 K) int, safe
 // The parameter `checker` is used to specify whether the given value is nil.
 func NewRedBlackKVTreeWithChecker[K comparable, V any](comparator func(v1, v2 K) int, checker NilChecker[V], safe ...bool) *RedBlackKVTree[K, V] {
 	t := NewRedBlackKVTree[K, V](comparator, safe...)
-	t.RegisterNilChecker(checker)
+	t.SetNilChecker(checker)
 	return t
 }
 
@@ -96,11 +97,11 @@ func RedBlackKVTreeInitFrom[K comparable, V any](tree *RedBlackKVTree[K, V], com
 	}
 }
 
-// RegisterNilChecker registers a custom nil checker function for the map values.
+// SetNilChecker registers a custom nil checker function for the map values.
 // This function is used to determine if a value should be considered as nil.
 // The nil checker function takes a value of type V and returns a boolean indicating
 // whether the value should be treated as nil.
-func (tree *RedBlackKVTree[K, V]) RegisterNilChecker(nilChecker NilChecker[V]) {
+func (tree *RedBlackKVTree[K, V]) SetNilChecker(nilChecker NilChecker[V]) {
 	tree.mu.Lock()
 	defer tree.mu.Unlock()
 	tree.nilChecker = nilChecker
@@ -108,12 +109,12 @@ func (tree *RedBlackKVTree[K, V]) RegisterNilChecker(nilChecker NilChecker[V]) {
 
 // isNil checks whether the given value is nil.
 // It first checks if a custom nil checker function is registered and uses it if available,
-// otherwise it performs a standard nil check using any(v) == nil.
-func (tree *RedBlackKVTree[K, V]) isNil(value V) bool {
+// otherwise it falls back to the default empty.IsNil function.
+func (tree *RedBlackKVTree[K, V]) isNil(v V) bool {
 	if tree.nilChecker != nil {
-		return tree.nilChecker(value)
+		return tree.nilChecker(v)
 	}
-	return any(value) == nil
+	return empty.IsNil(v)
 }
 
 // SetComparator sets/changes the comparator for sorting.
diff --git a/container/gtree/gtree_z_k_v_tree_test.go b/container/gtree/gtree_z_k_v_tree_test.go
index a769bf9b88c..92a229d2f8b 100644
--- a/container/gtree/gtree_z_k_v_tree_test.go
+++ b/container/gtree/gtree_z_k_v_tree_test.go
@@ -29,9 +29,10 @@ func Test_KVAVLTree_TypedNil(t *testing.T) {
 				avlTree.Set(i, s)
 			}
 		}
-		t.Assert(avlTree.Size(), 10)
+		t.Assert(avlTree.Size(), 5)
+
 		avlTree2 := gtree.NewAVLKVTree[int, *Student](gutil.ComparatorTStr[int], true)
-		avlTree2.RegisterNilChecker(func(student *Student) bool {
+		avlTree2.SetNilChecker(func(student *Student) bool {
 			return student == nil
 		})
 		for i := 0; i < 10; i++ {
@@ -62,9 +63,10 @@ func Test_KVBTree_TypedNil(t *testing.T) {
 				btree.Set(i, s)
 			}
 		}
-		t.Assert(btree.Size(), 10)
+		t.Assert(btree.Size(), 5)
+
 		btree2 := gtree.NewBKVTree[int, *Student](100, gutil.ComparatorTStr[int], true)
-		btree2.RegisterNilChecker(func(student *Student) bool {
+		btree2.SetNilChecker(func(student *Student) bool {
 			return student == nil
 		})
 		for i := 0; i < 10; i++ {
@@ -95,10 +97,10 @@ func Test_KVRedBlackTree_TypedNil(t *testing.T) {
 				redBlackTree.Set(i, s)
 			}
 		}
-		t.Assert(redBlackTree.Size(), 10)
-		redBlackTree2 := gtree.NewRedBlackKVTree[int, *Student](gutil.ComparatorTStr[int], true)
+		t.Assert(redBlackTree.Size(), 5)
 
-		redBlackTree2.RegisterNilChecker(func(student *Student) bool {
+		redBlackTree2 := gtree.NewRedBlackKVTree[int, *Student](gutil.ComparatorTStr[int], true)
+		redBlackTree2.SetNilChecker(func(student *Student) bool {
 			return student == nil
 		})
 		for i := 0; i < 10; i++ {
@@ -128,7 +130,8 @@ func Test_NewKVAVLTreeWithChecker_TypedNil(t *testing.T) {
 				avlTree.Set(i, s)
 			}
 		}
-		t.Assert(avlTree.Size(), 10)
+		t.Assert(avlTree.Size(), 5)
+
 		avlTree2 := gtree.NewAVLKVTreeWithChecker[int, *Student](gutil.ComparatorTStr[int], func(student *Student) bool {
 			return student == nil
 		}, true)
@@ -160,7 +163,8 @@ func Test_NewKVBTreeWithChecker_TypedNil(t *testing.T) {
 				btree.Set(i, s)
 			}
 		}
-		t.Assert(btree.Size(), 10)
+		t.Assert(btree.Size(), 5)
+
 		btree2 := gtree.NewBKVTreeWithChecker[int, *Student](100, gutil.ComparatorTStr[int], func(student *Student) bool {
 			return student == nil
 		}, true)
@@ -192,7 +196,8 @@ func Test_NewRedBlackKVTreeWithChecker_TypedNil(t *testing.T) {
 				redBlackTree.Set(i, s)
 			}
 		}
-		t.Assert(redBlackTree.Size(), 10)
+		t.Assert(redBlackTree.Size(), 5)
+
 		redBlackTree2 := gtree.NewRedBlackKVTreeWithChecker[int, *Student](gutil.ComparatorTStr[int], func(student *Student) bool {
 			return student == nil
 		}, true)
diff --git a/contrib/drivers/dm/dm_do_insert.go b/contrib/drivers/dm/dm_do_insert.go
index 72fc540b4f9..7f0aef7b44b 100644
--- a/contrib/drivers/dm/dm_do_insert.go
+++ b/contrib/drivers/dm/dm_do_insert.go
@@ -108,7 +108,7 @@ func (d *Driver) doMergeInsert(
 		one            = list[0]
 		oneLen         = len(one)
 		charL, charR   = d.GetChars()
-		conflictKeySet = gset.New(false)
+		conflictKeySet = gset.NewStrSet(false)
 
 		// queryHolders:	Handle data with Holder that need to be merged
 		// queryValues:		Handle data that need to be merged
diff --git a/contrib/drivers/gaussdb/gaussdb_do_insert.go b/contrib/drivers/gaussdb/gaussdb_do_insert.go
index 16193239c16..753e1ce7152 100644
--- a/contrib/drivers/gaussdb/gaussdb_do_insert.go
+++ b/contrib/drivers/gaussdb/gaussdb_do_insert.go
@@ -307,7 +307,7 @@ func (d *Driver) doMergeInsert(
 		one            = list[0]
 		oneLen         = len(one)
 		charL, charR   = d.GetChars()
-		conflictKeySet = gset.New(false)
+		conflictKeySet = gset.NewStrSet(false)
 
 		// queryHolders:	Handle data with Holder that need to be merged
 		// queryValues:		Handle data that need to be merged
diff --git a/contrib/drivers/mssql/mssql_do_insert.go b/contrib/drivers/mssql/mssql_do_insert.go
index 93bc17cfa81..fbdcba5d381 100644
--- a/contrib/drivers/mssql/mssql_do_insert.go
+++ b/contrib/drivers/mssql/mssql_do_insert.go
@@ -102,7 +102,7 @@ func (d *Driver) doMergeInsert(
 		one            = list[0]
 		oneLen         = len(one)
 		charL, charR   = d.GetChars()
-		conflictKeySet = gset.New(false)
+		conflictKeySet = gset.NewStrSet(false)
 
 		// queryHolders:	Handle data with Holder that need to be merged
 		// queryValues:		Handle data that need to be merged
diff --git a/contrib/drivers/oracle/oracle_do_insert.go b/contrib/drivers/oracle/oracle_do_insert.go
index 82f8373d5e4..ec0273f93f0 100644
--- a/contrib/drivers/oracle/oracle_do_insert.go
+++ b/contrib/drivers/oracle/oracle_do_insert.go
@@ -181,7 +181,7 @@ func (d *Driver) doMergeInsert(
 		one            = list[0]
 		oneLen         = len(one)
 		charL, charR   = d.GetChars()
-		conflictKeySet = gset.New(false)
+		conflictKeySet = gset.NewStrSet(false)
 
 		// queryHolders:	Handle data with Holder that need to be upsert
 		// queryValues:		Handle data that need to be upsert
diff --git a/database/gdb/gdb.go b/database/gdb/gdb.go
index 9c3bd7f8159..cc99d8e5a3d 100644
--- a/database/gdb/gdb.go
+++ b/database/gdb/gdb.go
@@ -513,18 +513,18 @@ type StatsItem interface {
 
 // Core is the base struct for database management.
 type Core struct {
-	db            DB              // DB interface object.
-	ctx           context.Context // Context for chaining operation only. Do not set a default value in Core initialization.
-	group         string          // Configuration group name.
-	schema        string          // Custom schema for this object.
-	debug         *gtype.Bool     // Enable debug mode for the database, which can be changed in runtime.
-	cache         *gcache.Cache   // Cache manager, SQL result cache only.
-	links         *gmap.Map       // links caches all created links by node.
-	logger        glog.ILogger    // Logger for logging functionality.
-	config        *ConfigNode     // Current config node.
-	localTypeMap  *gmap.StrAnyMap // Local type map for database field type conversion.
-	dynamicConfig dynamicConfig   // Dynamic configurations, which can be changed in runtime.
-	innerMemCache *gcache.Cache   // Internal memory cache for storing temporary data.
+	db            DB                               // DB interface object.
+	ctx           context.Context                  // Context for chaining operation only. Do not set a default value in Core initialization.
+	group         string                           // Configuration group name.
+	schema        string                           // Custom schema for this object.
+	debug         *gtype.Bool                      // Enable debug mode for the database, which can be changed in runtime.
+	cache         *gcache.Cache                    // Cache manager, SQL result cache only.
+	links         *gmap.KVMap[ConfigNode, *sql.DB] // links caches all created links by node.
+	logger        glog.ILogger                     // Logger for logging functionality.
+	config        *ConfigNode                      // Current config node.
+	localTypeMap  *gmap.StrAnyMap                  // Local type map for database field type conversion.
+	dynamicConfig dynamicConfig                    // Dynamic configurations, which can be changed in runtime.
+	innerMemCache *gcache.Cache                    // Internal memory cache for storing temporary data.
 }
 
 type dynamicConfig struct {
@@ -944,6 +944,9 @@ func NewByGroup(group ...string) (db DB, err error) {
 	)
 }
 
+// linksChecker is the checker function for links map.
+var linksChecker = func(v *sql.DB) bool { return v == nil }
+
 // newDBByConfigNode creates and returns an ORM object with given configuration node and group name.
 //
 // Very Note:
@@ -960,7 +963,7 @@ func newDBByConfigNode(node *ConfigNode, group string) (db DB, err error) {
 		group:         group,
 		debug:         gtype.NewBool(),
 		cache:         gcache.New(),
-		links:         gmap.New(true),
+		links:         gmap.NewKVMapWithChecker[ConfigNode, *sql.DB](linksChecker, true),
 		logger:        glog.New(),
 		config:        node,
 		localTypeMap:  gmap.NewStrAnyMap(true),
@@ -1127,7 +1130,7 @@ func (c *Core) getSqlDb(master bool, schema ...string) (sqlDb *sql.DB, err error
 
 	// Cache the underlying connection pool object by node.
 	var (
-		instanceCacheFunc = func() any {
+		instanceCacheFunc = func() *sql.DB {
 			if sqlDb, err = c.db.Open(node); err != nil {
 				return nil
 			}
@@ -1159,7 +1162,7 @@ func (c *Core) getSqlDb(master bool, schema ...string) (sqlDb *sql.DB, err error
 	)
 	if instanceValue != nil && sqlDb == nil {
 		// It reads from instance map.
-		sqlDb = instanceValue.(*sql.DB)
+		sqlDb = instanceValue
 	}
 	if node.Debug {
 		c.db.SetDebug(node.Debug)
diff --git a/database/gdb/gdb_core.go b/database/gdb/gdb_core.go
index 4bb712c02a1..4b23af05deb 100644
--- a/database/gdb/gdb_core.go
+++ b/database/gdb/gdb_core.go
@@ -113,19 +113,17 @@ func (c *Core) Close(ctx context.Context) (err error) {
 	if err = c.cache.Close(ctx); err != nil {
 		return err
 	}
-	c.links.LockFunc(func(m map[any]any) {
+	c.links.LockFunc(func(m map[ConfigNode]*sql.DB) {
 		for k, v := range m {
-			if db, ok := v.(*sql.DB); ok {
-				err = db.Close()
-				if err != nil {
-					err = gerror.WrapCode(gcode.CodeDbOperationError, err, `db.Close failed`)
-				}
-				intlog.Printf(ctx, `close link: %s, err: %v`, k, err)
-				if err != nil {
-					return
-				}
-				delete(m, k)
+			err = v.Close()
+			if err != nil {
+				err = gerror.WrapCode(gcode.CodeDbOperationError, err, `db.Close failed`)
+			}
+			intlog.Printf(ctx, `close link: %s, err: %v`, gconv.String(k), err)
+			if err != nil {
+				return
 			}
+			delete(m, k)
 		}
 	})
 	return
diff --git a/database/gdb/gdb_core_stats.go b/database/gdb/gdb_core_stats.go
index 8b64f14e842..0e89fbfe20e 100644
--- a/database/gdb/gdb_core_stats.go
+++ b/database/gdb/gdb_core_stats.go
@@ -30,14 +30,14 @@ func (item *localStatsItem) Stats() sql.DBStats {
 // Stats retrieves and returns the pool stat for all nodes that have been established.
 func (c *Core) Stats(ctx context.Context) []StatsItem {
 	var items = make([]StatsItem, 0)
-	c.links.Iterator(func(k, v any) bool {
-		var (
-			node  = k.(ConfigNode)
-			sqlDB = v.(*sql.DB)
-		)
+	c.links.Iterator(func(k ConfigNode, v *sql.DB) bool {
+		// Create a local copy of k to avoid loop variable address re-use issue
+		// In Go, loop variables are re-used with the same memory address across iterations,
+		// directly using &k would cause all localStatsItem instances to share the same address
+		node := k
 		items = append(items, &localStatsItem{
 			node:  &node,
-			stats: sqlDB.Stats(),
+			stats: v.Stats(),
 		})
 		return true
 	})
diff --git a/os/gcfg/gcfg_adapter_file.go b/os/gcfg/gcfg_adapter_file.go
index b81cf6f6f96..5b4f08e600f 100644
--- a/os/gcfg/gcfg_adapter_file.go
+++ b/os/gcfg/gcfg_adapter_file.go
@@ -32,11 +32,11 @@ var (
 
 // AdapterFile implements interface Adapter using file.
 type AdapterFile struct {
-	defaultFileNameOrPath *gtype.String    // Default configuration file name or file path.
-	searchPaths           *garray.StrArray // Searching the path array.
-	jsonMap               *gmap.StrAnyMap  // The pared JSON objects for configuration files.
-	violenceCheck         bool             // Whether it does violence check in value index searching. It affects the performance when set true(false in default).
-	watchers              *WatcherRegistry // Watchers for watching file changes.
+	defaultFileNameOrPath *gtype.String                    // Default configuration file name or file path.
+	searchPaths           *garray.StrArray                 // Searching the path array.
+	jsonMap               *gmap.KVMap[string, *gjson.Json] // The parsed JSON objects for configuration files.
+	violenceCheck         bool                             // Whether it does violence check in value index searching. It affects the performance when set true(false in default).
+	watchers              *WatcherRegistry                 // Watchers for watching file changes.
 }
 
 const (
@@ -58,6 +58,9 @@ var (
 
 	// Prefix array for trying searching in the local system.
 	localSystemTryFolders = []string{"", "config/", "manifest/config"}
+
+	// jsonMapChecker is the checker for JSON map.
+	jsonMapChecker = func(v *gjson.Json) bool { return v == nil }
 )
 
 // NewAdapterFile returns a new configuration management object.
@@ -78,7 +81,7 @@ func NewAdapterFile(fileNameOrPath ...string) (*AdapterFile, error) {
 	config := &AdapterFile{
 		defaultFileNameOrPath: gtype.NewString(usedFileNameOrPath),
 		searchPaths:           garray.NewStrArray(true),
-		jsonMap:               gmap.NewStrAnyMap(true),
+		jsonMap:               gmap.NewKVMapWithChecker[string, *gjson.Json](jsonMapChecker, true),
 		watchers:              NewWatcherRegistry(),
 	}
 	// Customized dir path from env/cmd.
@@ -257,7 +260,7 @@ func (a *AdapterFile) getJson(fileNameOrPath ...string) (configJson *gjson.Json,
 		usedFileNameOrPath = fileNameOrPath[0]
 	}
 	// It uses JSON map to cache specified configuration file content.
-	result := a.jsonMap.GetOrSetFuncLock(usedFileNameOrPath, func() any {
+	result := a.jsonMap.GetOrSetFuncLock(usedFileNameOrPath, func() *gjson.Json {
 		var (
 			content  string
 			filePath string
@@ -326,7 +329,7 @@ func (a *AdapterFile) getJson(fileNameOrPath ...string) (configJson *gjson.Json,
 		return configJson
 	})
 	if result != nil {
-		return result.(*gjson.Json), err
+		return result, err
 	}
 	return
 }