github.com/keysonzzz/kmg@v0.0.0-20151121023212-05317bfd7d39/kmgType/PtrType.go (about)

     1  package kmgType
     2  
     3  import (
     4  	"fmt"
     5  	"reflect"
     6  )
     7  
     8  //path -> pass to RefType
     9  type PtrType struct {
    10  	reflectTypeGetterImp
    11  	elemType KmgType
    12  }
    13  
    14  func (t *PtrType) init() (err error) {
    15  	if t.elemType != nil {
    16  		return
    17  	}
    18  	t.elemType, err = TypeOf(t.GetReflectType().Elem())
    19  	return
    20  }
    21  func (t *PtrType) SaveByPath(inV *reflect.Value, path Path, value string) error {
    22  	err := t.init()
    23  	if err != nil {
    24  		return err
    25  	}
    26  	//create
    27  	if inV.IsNil() {
    28  		if inV.CanSet() {
    29  			inV.Set(reflect.New(t.GetReflectType().Elem()))
    30  		} else {
    31  			*inV = reflect.New(t.GetReflectType().Elem())
    32  		}
    33  	}
    34  	//a elem of a ptr CanSet must be true.
    35  	elemV := inV.Elem()
    36  	if len(path) >= 1 {
    37  		return t.elemType.SaveByPath(&elemV, path[1:], value)
    38  	}
    39  	return nil
    40  }
    41  func (t *PtrType) GetElemByString(v reflect.Value, k string) (ev reflect.Value, et KmgType, err error) {
    42  	err = t.init()
    43  	if err != nil {
    44  		return
    45  	}
    46  	if v.IsNil() {
    47  		err = fmt.Errorf("[PtrType.GetElemByString] get null pointer k:%s", k)
    48  		return
    49  	}
    50  	ev = v.Elem()
    51  	et = t.elemType
    52  	return
    53  }
    54  func (t *PtrType) DeleteByPath(v *reflect.Value, path Path) (err error) {
    55  	if len(path) > 1 {
    56  		return passThougthDeleteByPath(t, v, path)
    57  	} else if len(path) == 0 {
    58  		return fmt.Errorf("[PtrType.DeleteByPath] delete ptr with no path.")
    59  	}
    60  	nilPtr := reflect.Zero(t.GetReflectType())
    61  	if v.CanSet() {
    62  		v.Set(nilPtr)
    63  	} else {
    64  		*v = nilPtr
    65  	}
    66  	return nil
    67  }