github.com/wangyougui/gf/v2@v2.6.5/container/gtype/gtype_string.go (about) 1 // Copyright GoFrame Author(https://goframe.org). All Rights Reserved. 2 // 3 // This Source Code Form is subject to the terms of the MIT License. 4 // If a copy of the MIT was not distributed with this file, 5 // You can obtain one at https://github.com/wangyougui/gf. 6 7 package gtype 8 9 import ( 10 "bytes" 11 "sync/atomic" 12 13 "github.com/wangyougui/gf/v2/util/gconv" 14 ) 15 16 // String is a struct for concurrent-safe operation for type string. 17 type String struct { 18 value atomic.Value 19 } 20 21 // NewString creates and returns a concurrent-safe object for string type, 22 // with given initial value `value`. 23 func NewString(value ...string) *String { 24 t := &String{} 25 if len(value) > 0 { 26 t.value.Store(value[0]) 27 } 28 return t 29 } 30 31 // Clone clones and returns a new concurrent-safe object for string type. 32 func (v *String) Clone() *String { 33 return NewString(v.Val()) 34 } 35 36 // Set atomically stores `value` into t.value and returns the previous value of t.value. 37 func (v *String) Set(value string) (old string) { 38 old = v.Val() 39 v.value.Store(value) 40 return 41 } 42 43 // Val atomically loads and returns t.value. 44 func (v *String) Val() string { 45 s := v.value.Load() 46 if s != nil { 47 return s.(string) 48 } 49 return "" 50 } 51 52 // String implements String interface for string printing. 53 func (v *String) String() string { 54 return v.Val() 55 } 56 57 // MarshalJSON implements the interface MarshalJSON for json.Marshal. 58 func (v String) MarshalJSON() ([]byte, error) { 59 return []byte(`"` + v.Val() + `"`), nil 60 } 61 62 // UnmarshalJSON implements the interface UnmarshalJSON for json.Unmarshal. 63 func (v *String) UnmarshalJSON(b []byte) error { 64 v.Set(string(bytes.Trim(b, `"`))) 65 return nil 66 } 67 68 // UnmarshalValue is an interface implement which sets any type of value for `v`. 69 func (v *String) UnmarshalValue(value interface{}) error { 70 v.Set(gconv.String(value)) 71 return nil 72 } 73 74 // DeepCopy implements interface for deep copy of current type. 75 func (v *String) DeepCopy() interface{} { 76 if v == nil { 77 return nil 78 } 79 return NewString(v.Val()) 80 }