go/arrow/array/numericbuilder.gen.go.tmpl

// 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 array

import (
	"github.com/apache/arrow/go/arrow"
	"github.com/apache/arrow/go/arrow/internal/bitutil"
	"github.com/apache/arrow/go/arrow/internal/debug"
	"github.com/apache/arrow/go/arrow/memory"
)

{{range .In}}

type {{.Name}}Builder struct {
	builder

{{if .Opt.Parametric -}}
	dtype    *arrow.{{.Name}}Type
{{end -}}
	data    *memory.Buffer
	rawData []{{or .QualifiedType .Type}}
}

{{if .Opt.Parametric}}
func New{{.Name}}Builder(mem memory.Allocator, dtype *arrow.{{.Name}}Type) *{{.Name}}Builder {
	return &{{.Name}}Builder{builder: builder{refCount:1, mem: mem}, dtype: dtype}
}
{{else}}
func New{{.Name}}Builder(mem memory.Allocator) *{{.Name}}Builder {
	return &{{.Name}}Builder{builder: builder{refCount:1, mem: mem}}
}
{{end}}

// Release decreases the reference count by 1.
// When the reference count goes to zero, the memory is freed.
func (b *{{.Name}}Builder) Release() {
	debug.Assert(atomic.LoadInt64(&b.refCount) > 0, "too many releases")

	if atomic.AddInt64(&b.refCount, -1) == 0 {
		if b.nullBitmap != nil {
			b.nullBitmap.Release()
			b.nullBitmap = nil
		}
		if b.data != nil {
			b.data.Release()
			b.data = nil
			b.rawData = nil
		}
	}
}

func (b *{{.Name}}Builder) Append(v {{or .QualifiedType .Type}}) {
	b.Reserve(1)
	b.UnsafeAppend(v)
}

func (b *{{.Name}}Builder) AppendNull() {
	b.Reserve(1)
	b.UnsafeAppendBoolToBitmap(false)
}

func (b *{{.Name}}Builder) UnsafeAppend(v {{or .QualifiedType .Type}}) {
	bitutil.SetBit(b.nullBitmap.Bytes(), b.length)
	b.rawData[b.length] = v
	b.length++
}

func (b *{{.Name}}Builder) UnsafeAppendBoolToBitmap(isValid bool) {
	if isValid {
		bitutil.SetBit(b.nullBitmap.Bytes(), b.length)
	} else {
		b.nulls++
	}
	b.length++
}

// AppendValues will append the values in the v slice. The valid slice determines which values
// in v are valid (not null). The valid slice must either be empty or be equal in length to v. If empty,
// all values in v are appended and considered valid.
func (b *{{.Name}}Builder) AppendValues(v []{{or .QualifiedType .Type}}, valid []bool) {
	if len(v) != len(valid) && len(valid) != 0 {
		panic("len(v) != len(valid) && len(valid) != 0")
	}

	if len(v) == 0 {
		return
	}

	b.Reserve(len(v))
	arrow.{{.Name}}Traits.Copy(b.rawData[b.length:], v)
	b.builder.unsafeAppendBoolsToBitmap(valid, len(v))
}

func (b *{{.Name}}Builder) init(capacity int) {
	b.builder.init(capacity)

	b.data = memory.NewResizableBuffer(b.mem)
	bytesN := arrow.{{.Name}}Traits.BytesRequired(capacity)
	b.data.Resize(bytesN)
	b.rawData = arrow.{{.Name}}Traits.CastFromBytes(b.data.Bytes())
}

// Reserve ensures there is enough space for appending n elements
// by checking the capacity and calling Resize if necessary.
func (b *{{.Name}}Builder) Reserve(n int) {
	b.builder.reserve(n, b.Resize)
}

// Resize adjusts the space allocated by b to n elements. If n is greater than b.Cap(),
// additional memory will be allocated. If n is smaller, the allocated memory may reduced.
func (b *{{.Name}}Builder) Resize(n int) {
	nBuilder := n
	if n < minBuilderCapacity {
		n = minBuilderCapacity
	}

	if b.capacity == 0 {
		b.init(n)
	} else {
		b.builder.resize(nBuilder, b.init)
		b.data.Resize(arrow.{{.Name}}Traits.BytesRequired(n))
		b.rawData = arrow.{{.Name}}Traits.CastFromBytes(b.data.Bytes())
	}
}

// NewArray creates a {{.Name}} array from the memory buffers used by the builder and resets the {{.Name}}Builder
// so it can be used to build a new array.
func (b *{{.Name}}Builder) NewArray() Interface {
	return b.New{{.Name}}Array()
}

// New{{.Name}}Array creates a {{.Name}} array from the memory buffers used by the builder and resets the {{.Name}}Builder
// so it can be used to build a new array.
func (b *{{.Name}}Builder) New{{.Name}}Array() (a *{{.Name}}) {
	data := b.newData()
	a = New{{.Name}}Data(data)
	data.Release()
	return
}

func (b *{{.Name}}Builder) newData() (data *Data) {
	bytesRequired := arrow.{{.Name}}Traits.BytesRequired(b.length)
	if bytesRequired > 0 && bytesRequired < b.data.Len() {
		// trim buffers
		b.data.Resize(bytesRequired)
	}
{{if .Opt.Parametric -}}
	data = NewData(b.dtype, b.length, []*memory.Buffer{b.nullBitmap, b.data}, nil, b.nulls, 0)
{{else -}}
	data = NewData(arrow.PrimitiveTypes.{{.Name}}, b.length, []*memory.Buffer{b.nullBitmap, b.data}, nil, b.nulls, 0)
{{end -}}
	b.reset()

	if b.data != nil {
		b.data.Release()
		b.data = nil
		b.rawData = nil
	}

	return
}
{{end}}

var (
{{- range .In}}
	_ Builder = (*{{.Name}}Builder)(nil)
{{- end}}
)