| // 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 ( |
| "math" |
| "sync/atomic" |
| |
| "github.com/apache/arrow/go/arrow" |
| "github.com/apache/arrow/go/arrow/internal/debug" |
| "github.com/apache/arrow/go/arrow/memory" |
| ) |
| |
| const ( |
| binaryArrayMaximumCapacity = math.MaxInt32 |
| ) |
| |
| // A BinaryBuilder is used to build a Binary array using the Append methods. |
| type BinaryBuilder struct { |
| builder |
| |
| dtype arrow.BinaryDataType |
| offsets *int32BufferBuilder |
| values *byteBufferBuilder |
| } |
| |
| func NewBinaryBuilder(mem memory.Allocator, dtype arrow.BinaryDataType) *BinaryBuilder { |
| b := &BinaryBuilder{ |
| builder: builder{refCount: 1, mem: mem}, |
| dtype: dtype, |
| offsets: newInt32BufferBuilder(mem), |
| values: newByteBufferBuilder(mem), |
| } |
| return b |
| } |
| |
| // Release decreases the reference count by 1. |
| // When the reference count goes to zero, the memory is freed. |
| // Release may be called simultaneously from multiple goroutines. |
| func (b *BinaryBuilder) 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.offsets != nil { |
| b.offsets.Release() |
| b.offsets = nil |
| } |
| if b.values != nil { |
| b.values.Release() |
| b.values = nil |
| } |
| } |
| } |
| |
| func (b *BinaryBuilder) Append(v []byte) { |
| b.Reserve(1) |
| b.appendNextOffset() |
| b.values.Append(v) |
| b.UnsafeAppendBoolToBitmap(true) |
| } |
| |
| func (b *BinaryBuilder) AppendString(v string) { |
| b.Append([]byte(v)) |
| } |
| |
| func (b *BinaryBuilder) AppendNull() { |
| b.Reserve(1) |
| b.appendNextOffset() |
| b.UnsafeAppendBoolToBitmap(false) |
| } |
| |
| // 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 *BinaryBuilder) AppendValues(v [][]byte, 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)) |
| for _, vv := range v { |
| b.appendNextOffset() |
| b.values.Append(vv) |
| } |
| |
| b.builder.unsafeAppendBoolsToBitmap(valid, len(v)) |
| } |
| |
| // AppendStringValues 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 *BinaryBuilder) AppendStringValues(v []string, 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)) |
| for _, vv := range v { |
| b.appendNextOffset() |
| b.values.Append([]byte(vv)) |
| } |
| |
| b.builder.unsafeAppendBoolsToBitmap(valid, len(v)) |
| } |
| |
| func (b *BinaryBuilder) Value(i int) []byte { |
| offsets := b.offsets.Values() |
| start := int(offsets[i]) |
| var end int |
| if i == (b.length - 1) { |
| end = b.values.Len() |
| } else { |
| end = int(offsets[i+1]) |
| } |
| return b.values.Bytes()[start:end] |
| } |
| |
| func (b *BinaryBuilder) init(capacity int) { |
| b.builder.init(capacity) |
| b.offsets.resize((capacity + 1) * arrow.Int32SizeBytes) |
| } |
| |
| // DataLen returns the number of bytes in the data array. |
| func (b *BinaryBuilder) DataLen() int { return b.values.length } |
| |
| // DataCap returns the total number of bytes that can be stored |
| // without allocating additional memory. |
| func (b *BinaryBuilder) DataCap() int { return b.values.capacity } |
| |
| // Reserve ensures there is enough space for appending n elements |
| // by checking the capacity and calling Resize if necessary. |
| func (b *BinaryBuilder) Reserve(n int) { |
| b.builder.reserve(n, b.Resize) |
| } |
| |
| // ReserveData ensures there is enough space for appending n bytes |
| // by checking the capacity and resizing the data buffer if necessary. |
| func (b *BinaryBuilder) ReserveData(n int) { |
| if b.values.capacity < b.values.length+n { |
| b.values.resize(b.values.Len() + n) |
| } |
| } |
| |
| // 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 be reduced. |
| func (b *BinaryBuilder) Resize(n int) { |
| b.offsets.resize((n + 1) * arrow.Int32SizeBytes) |
| b.builder.resize(n, b.init) |
| } |
| |
| // NewArray creates a Binary array from the memory buffers used by the builder and resets the BinaryBuilder |
| // so it can be used to build a new array. |
| func (b *BinaryBuilder) NewArray() Interface { |
| return b.NewBinaryArray() |
| } |
| |
| // NewBinaryArray creates a Binary array from the memory buffers used by the builder and resets the BinaryBuilder |
| // so it can be used to build a new array. |
| func (b *BinaryBuilder) NewBinaryArray() (a *Binary) { |
| data := b.newData() |
| a = NewBinaryData(data) |
| data.Release() |
| return |
| } |
| |
| func (b *BinaryBuilder) newData() (data *Data) { |
| b.appendNextOffset() |
| offsets, values := b.offsets.Finish(), b.values.Finish() |
| data = NewData(b.dtype, b.length, []*memory.Buffer{b.nullBitmap, offsets, values}, nil, b.nulls, 0) |
| if offsets != nil { |
| offsets.Release() |
| } |
| |
| if values != nil { |
| values.Release() |
| } |
| |
| b.builder.reset() |
| |
| return |
| } |
| |
| func (b *BinaryBuilder) appendNextOffset() { |
| numBytes := b.values.Len() |
| // TODO(sgc): check binaryArrayMaximumCapacity? |
| b.offsets.AppendValue(int32(numBytes)) |
| } |
| |
| var ( |
| _ Builder = (*BinaryBuilder)(nil) |
| ) |