-
Notifications
You must be signed in to change notification settings - Fork 3.5k
/
datatype_nested.go
180 lines (156 loc) · 4.99 KB
/
datatype_nested.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package arrow
import (
"fmt"
"reflect"
"strings"
)
// ListType describes a nested type in which each array slot contains
// a variable-size sequence of values, all having the same relative type.
type ListType struct {
elem DataType // DataType of the list's elements
}
// ListOf returns the list type with element type t.
// For example, if t represents int32, ListOf(t) represents []int32.
//
// ListOf panics if t is nil or invalid.
func ListOf(t DataType) *ListType {
if t == nil {
panic("arrow: nil DataType")
}
return &ListType{elem: t}
}
func (*ListType) ID() Type { return LIST }
func (*ListType) Name() string { return "list" }
func (t *ListType) String() string { return fmt.Sprintf("list<item: %v>", t.elem) }
// Elem returns the ListType's element type.
func (t *ListType) Elem() DataType { return t.elem }
// FixedSizeListType describes a nested type in which each array slot contains
// a fixed-size sequence of values, all having the same relative type.
type FixedSizeListType struct {
n int32 // number of elements in the list
elem DataType // DataType of the list's elements
}
// FixedSizeListOf returns the list type with element type t.
// For example, if t represents int32, FixedSizeListOf(10, t) represents [10]int32.
//
// FixedSizeListOf panics if t is nil or invalid.
// FixedSizeListOf panics if n is <= 0.
func FixedSizeListOf(n int32, t DataType) *FixedSizeListType {
if t == nil {
panic("arrow: nil DataType")
}
if n <= 0 {
panic("arrow: invalid size")
}
return &FixedSizeListType{elem: t, n: n}
}
func (*FixedSizeListType) ID() Type { return FIXED_SIZE_LIST }
func (*FixedSizeListType) Name() string { return "fixed_size_list" }
func (t *FixedSizeListType) String() string {
return fmt.Sprintf("fixed_size_list<item: %v>[%d]", t.elem, t.n)
}
// Elem returns the FixedSizeListType's element type.
func (t *FixedSizeListType) Elem() DataType { return t.elem }
// Len returns the FixedSizeListType's size.
func (t *FixedSizeListType) Len() int32 { return t.n }
// StructType describes a nested type parameterized by an ordered sequence
// of relative types, called its fields.
type StructType struct {
fields []Field
index map[string]int
meta Metadata
}
// StructOf returns the struct type with fields fs.
//
// StructOf panics if there are duplicated fields.
// StructOf panics if there is a field with an invalid DataType.
func StructOf(fs ...Field) *StructType {
n := len(fs)
if n == 0 {
return &StructType{}
}
t := &StructType{
fields: make([]Field, n),
index: make(map[string]int, n),
}
for i, f := range fs {
if f.Type == nil {
panic("arrow: field with nil DataType")
}
t.fields[i] = Field{
Name: f.Name,
Type: f.Type,
Nullable: f.Nullable,
Metadata: f.Metadata.clone(),
}
if _, dup := t.index[f.Name]; dup {
panic(fmt.Errorf("arrow: duplicate field with name %q", f.Name))
}
t.index[f.Name] = i
}
return t
}
func (*StructType) ID() Type { return STRUCT }
func (*StructType) Name() string { return "struct" }
func (t *StructType) String() string {
o := new(strings.Builder)
o.WriteString("struct<")
for i, f := range t.fields {
if i > 0 {
o.WriteString(", ")
}
o.WriteString(fmt.Sprintf("%s: %v", f.Name, f.Type))
}
o.WriteString(">")
return o.String()
}
func (t *StructType) Fields() []Field { return t.fields }
func (t *StructType) Field(i int) Field { return t.fields[i] }
func (t *StructType) FieldByName(name string) (Field, bool) {
i, ok := t.index[name]
if !ok {
return Field{}, false
}
return t.fields[i], true
}
type Field struct {
Name string // Field name
Type DataType // The field's data type
Nullable bool // Fields can be nullable
Metadata Metadata // The field's metadata, if any
}
func (f Field) HasMetadata() bool { return f.Metadata.Len() != 0 }
func (f Field) Equal(o Field) bool {
return reflect.DeepEqual(f, o)
}
func (f Field) String() string {
o := new(strings.Builder)
nullable := ""
if f.Nullable {
nullable = ", nullable"
}
fmt.Fprintf(o, "%s: type=%v%v", f.Name, f.Type, nullable)
if f.HasMetadata() {
fmt.Fprintf(o, "\n%*.smetadata: %v", len(f.Name)+2, "", f.Metadata)
}
return o.String()
}
var (
_ DataType = (*ListType)(nil)
_ DataType = (*StructType)(nil)
)