Tags    []Tag    `xml:"Tag,omitempty" json:"Tag,omitempty"`
}

var errDuplicateTagKey = Errorf("Duplicate Tag Keys are not allowed")

// isEmpty returns true if Tags field is null
func (a And) isEmpty() bool {
	return len(a.Tags) == 0 && a.Prefix == ""
}

// Validate - validates the And field
func (a And) Validate() error {
	if a.ContainsDuplicateTag() {
		return errDuplicateTagKey
	}

	ObjectSizeLessThan    int64    `xml:"ObjectSizeLessThan,omitempty"`
	Prefix                Prefix   `xml:"Prefix,omitempty"`
	Tags                  []Tag    `xml:"Tag,omitempty"`
}

// isEmpty returns true if Tags field is null
func (a And) isEmpty() bool {
	return len(a.Tags) == 0 && !a.Prefix.set &&
		a.ObjectSizeGreaterThan == 0 && a.ObjectSizeLessThan == 0
}

// Validate - validates the And field
func (a And) Validate() error {