lbry.go/int16.go
2016-11-12 11:45:55 +10:00

129 lines
2.5 KiB
Go

package null
import (
"bytes"
"database/sql/driver"
"encoding/json"
"fmt"
"math"
"strconv"
"gopkg.in/nullbio/null.v6/convert"
)
// Int16 is an nullable int16.
type Int16 struct {
Int16 int16
Valid bool
}
// NewInt16 creates a new Int16
func NewInt16(i int16, valid bool) Int16 {
return Int16{
Int16: i,
Valid: valid,
}
}
// Int16From creates a new Int16 that will always be valid.
func Int16From(i int16) Int16 {
return NewInt16(i, true)
}
// Int16FromPtr creates a new Int16 that be null if i is nil.
func Int16FromPtr(i *int16) Int16 {
if i == nil {
return NewInt16(0, false)
}
return NewInt16(*i, true)
}
// UnmarshalJSON implements json.Unmarshaler.
func (i *Int16) UnmarshalJSON(data []byte) error {
if bytes.Equal(data, NullBytes) {
i.Valid = false
i.Int16 = 0
return nil
}
var x int64
if err := json.Unmarshal(data, &x); err != nil {
return err
}
if x > math.MaxInt16 {
return fmt.Errorf("json: %d overflows max int16 value", x)
}
i.Int16 = int16(x)
i.Valid = true
return nil
}
// UnmarshalText implements encoding.TextUnmarshaler.
func (i *Int16) UnmarshalText(text []byte) error {
if text == nil || len(text) == 0 {
i.Valid = false
return nil
}
var err error
res, err := strconv.ParseInt(string(text), 10, 16)
i.Valid = err == nil
if i.Valid {
i.Int16 = int16(res)
}
return err
}
// MarshalJSON implements json.Marshaler.
func (i Int16) MarshalJSON() ([]byte, error) {
if !i.Valid {
return NullBytes, nil
}
return []byte(strconv.FormatInt(int64(i.Int16), 10)), nil
}
// MarshalText implements encoding.TextMarshaler.
func (i Int16) MarshalText() ([]byte, error) {
if !i.Valid {
return []byte{}, nil
}
return []byte(strconv.FormatInt(int64(i.Int16), 10)), nil
}
// SetValid changes this Int16's value and also sets it to be non-null.
func (i *Int16) SetValid(n int16) {
i.Int16 = n
i.Valid = true
}
// Ptr returns a pointer to this Int16's value, or a nil pointer if this Int16 is null.
func (i Int16) Ptr() *int16 {
if !i.Valid {
return nil
}
return &i.Int16
}
// IsZero returns true for invalid Int16's, for future omitempty support (Go 1.4?)
func (i Int16) IsZero() bool {
return !i.Valid
}
// Scan implements the Scanner interface.
func (i *Int16) Scan(value interface{}) error {
if value == nil {
i.Int16, i.Valid = 0, false
return nil
}
i.Valid = true
return convert.ConvertAssign(&i.Int16, value)
}
// Value implements the driver Valuer interface.
func (i Int16) Value() (driver.Value, error) {
if !i.Valid {
return nil, nil
}
return int64(i.Int16), nil
}