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// 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.
import { Vector } from './vector.mjs';
import { makeData } from './data.mjs';
import { MapRow, kKeys } from './row/map.mjs';
import { strideForType, } from './type.mjs';
import { createIsValidFunction } from './builder/valid.mjs';
import { BitmapBufferBuilder, DataBufferBuilder, OffsetsBufferBuilder } from './builder/buffer.mjs';
/**
* An abstract base class for types that construct Arrow Vectors from arbitrary JavaScript values.
*
* A `Builder` is responsible for writing arbitrary JavaScript values
* to ArrayBuffers and/or child Builders according to the Arrow specification
* for each DataType, creating or resizing the underlying ArrayBuffers as necessary.
*
* The `Builder` for each Arrow `DataType` handles converting and appending
* values for a given `DataType`. The high-level {@link makeBuilder `makeBuilder()`} convenience
* method creates the specific `Builder` subclass for the supplied `DataType`.
*
* Once created, `Builder` instances support both appending values to the end
* of the `Builder`, and random-access writes to specific indices
* (`Builder.prototype.append(value)` is a convenience method for
* `builder.set(builder.length, value)`). Appending or setting values beyond the
* Builder's current length may cause the builder to grow its underlying buffers
* or child Builders (if applicable) to accommodate the new values.
*
* After enough values have been written to a `Builder`, `Builder.prototype.flush()`
* will commit the values to the underlying ArrayBuffers (or child Builders). The
* internal Builder state will be reset, and an instance of `Data<T>` is returned.
* Alternatively, `Builder.prototype.toVector()` will flush the `Builder` and return
* an instance of `Vector<T>` instead.
*
* When there are no more values to write, use `Builder.prototype.finish()` to
* finalize the `Builder`. This does not reset the internal state, so it is
* necessary to call `Builder.prototype.flush()` or `toVector()` one last time
* if there are still values queued to be flushed.
*
* Note: calling `Builder.prototype.finish()` is required when using a `DictionaryBuilder`,
* because this is when it flushes the values that have been enqueued in its internal
* dictionary's `Builder`, and creates the `dictionaryVector` for the `Dictionary` `DataType`.
*
* @example
* ```ts
* import { Builder, Utf8 } from 'apache-arrow';
*
* const utf8Builder = makeBuilder({
* type: new Utf8(),
* nullValues: [null, 'n/a']
* });
*
* utf8Builder
* .append('hello')
* .append('n/a')
* .append('world')
* .append(null);
*
* const utf8Vector = utf8Builder.finish().toVector();
*
* console.log(utf8Vector.toJSON());
* // > ["hello", null, "world", null]
* ```
*
* @typeparam T The `DataType` of this `Builder`.
* @typeparam TNull The type(s) of values which will be considered null-value sentinels.
*/
export class Builder {
/**
* Construct a builder with the given Arrow DataType with optional null values,
* which will be interpreted as "null" when set or appended to the `Builder`.
* @param {{ type: T, nullValues?: any[] }} options A `BuilderOptions` object used to create this `Builder`.
*/
constructor({ 'type': type, 'nullValues': nulls }) {
/**
* The number of values written to the `Builder` that haven't been flushed yet.
* @readonly
*/
this.length = 0;
/**
* A boolean indicating whether `Builder.prototype.finish()` has been called on this `Builder`.
* @readonly
*/
this.finished = false;
this.type = type;
this.children = [];
this.nullValues = nulls;
this.stride = strideForType(type);
this._nulls = new BitmapBufferBuilder();
if (nulls && nulls.length > 0) {
this._isValid = createIsValidFunction(nulls);
}
}
/** @nocollapse */
// @ts-ignore
static throughNode(options) {
throw new Error(`"throughNode" not available in this environment`);
}
/** @nocollapse */
// @ts-ignore
static throughDOM(options) {
throw new Error(`"throughDOM" not available in this environment`);
}
/**
* Flush the `Builder` and return a `Vector<T>`.
* @returns {Vector<T>} A `Vector<T>` of the flushed values.
*/
toVector() { return new Vector([this.flush()]); }
get ArrayType() { return this.type.ArrayType; }
get nullCount() { return this._nulls.numInvalid; }
get numChildren() { return this.children.length; }
/**
* @returns The aggregate length (in bytes) of the values that have been written.
*/
get byteLength() {
let size = 0;
const { _offsets, _values, _nulls, _typeIds, children } = this;
_offsets && (size += _offsets.byteLength);
_values && (size += _values.byteLength);
_nulls && (size += _nulls.byteLength);
_typeIds && (size += _typeIds.byteLength);
return children.reduce((size, child) => size + child.byteLength, size);
}
/**
* @returns The aggregate number of rows that have been reserved to write new values.
*/
get reservedLength() {
return this._nulls.reservedLength;
}
/**
* @returns The aggregate length (in bytes) that has been reserved to write new values.
*/
get reservedByteLength() {
let size = 0;
this._offsets && (size += this._offsets.reservedByteLength);
this._values && (size += this._values.reservedByteLength);
this._nulls && (size += this._nulls.reservedByteLength);
this._typeIds && (size += this._typeIds.reservedByteLength);
return this.children.reduce((size, child) => size + child.reservedByteLength, size);
}
get valueOffsets() { return this._offsets ? this._offsets.buffer : null; }
get values() { return this._values ? this._values.buffer : null; }
get nullBitmap() { return this._nulls ? this._nulls.buffer : null; }
get typeIds() { return this._typeIds ? this._typeIds.buffer : null; }
/**
* Appends a value (or null) to this `Builder`.
* This is equivalent to `builder.set(builder.length, value)`.
* @param {T['TValue'] | TNull } value The value to append.
*/
append(value) { return this.set(this.length, value); }
/**
* Validates whether a value is valid (true), or null (false)
* @param {T['TValue'] | TNull } value The value to compare against null the value representations
*/
isValid(value) { return this._isValid(value); }
/**
* Write a value (or null-value sentinel) at the supplied index.
* If the value matches one of the null-value representations, a 1-bit is
* written to the null `BitmapBufferBuilder`. Otherwise, a 0 is written to
* the null `BitmapBufferBuilder`, and the value is passed to
* `Builder.prototype.setValue()`.
* @param {number} index The index of the value to write.
* @param {T['TValue'] | TNull } value The value to write at the supplied index.
* @returns {this} The updated `Builder` instance.
*/
set(index, value) {
if (this.setValid(index, this.isValid(value))) {
this.setValue(index, value);
}
return this;
}
/**
* Write a value to the underlying buffers at the supplied index, bypassing
* the null-value check. This is a low-level method that
* @param {number} index
* @param {T['TValue'] | TNull } value
*/
setValue(index, value) { this._setValue(this, index, value); }
setValid(index, valid) {
this.length = this._nulls.set(index, +valid).length;
return valid;
}
// @ts-ignore
addChild(child, name = `${this.numChildren}`) {
throw new Error(`Cannot append children to non-nested type "${this.type}"`);
}
/**
* Retrieve the child `Builder` at the supplied `index`, or null if no child
* exists at that index.
* @param {number} index The index of the child `Builder` to retrieve.
* @returns {Builder | null} The child Builder at the supplied index or null.
*/
getChildAt(index) {
return this.children[index] || null;
}
/**
* Commit all the values that have been written to their underlying
* ArrayBuffers, including any child Builders if applicable, and reset
* the internal `Builder` state.
* @returns A `Data<T>` of the buffers and children representing the values written.
*/
flush() {
let data;
let typeIds;
let nullBitmap;
let valueOffsets;
const { type, length, nullCount, _typeIds, _offsets, _values, _nulls } = this;
if (typeIds = _typeIds === null || _typeIds === void 0 ? void 0 : _typeIds.flush(length)) { // Unions
// DenseUnions
valueOffsets = _offsets === null || _offsets === void 0 ? void 0 : _offsets.flush(length);
}
else if (valueOffsets = _offsets === null || _offsets === void 0 ? void 0 : _offsets.flush(length)) { // Variable-width primitives (Binary, Utf8), and Lists
// Binary, Utf8
data = _values === null || _values === void 0 ? void 0 : _values.flush(_offsets.last());
}
else { // Fixed-width primitives (Int, Float, Decimal, Time, Timestamp, and Interval)
data = _values === null || _values === void 0 ? void 0 : _values.flush(length);
}
if (nullCount > 0) {
nullBitmap = _nulls === null || _nulls === void 0 ? void 0 : _nulls.flush(length);
}
const children = this.children.map((child) => child.flush());
this.clear();
return makeData({
type, length, nullCount,
children, 'child': children[0],
data, typeIds, nullBitmap, valueOffsets,
});
}
/**
* Finalize this `Builder`, and child builders if applicable.
* @returns {this} The finalized `Builder` instance.
*/
finish() {
this.finished = true;
for (const child of this.children)
child.finish();
return this;
}
/**
* Clear this Builder's internal state, including child Builders if applicable, and reset the length to 0.
* @returns {this} The cleared `Builder` instance.
*/
clear() {
var _a, _b, _c, _d;
this.length = 0;
(_a = this._nulls) === null || _a === void 0 ? void 0 : _a.clear();
(_b = this._values) === null || _b === void 0 ? void 0 : _b.clear();
(_c = this._offsets) === null || _c === void 0 ? void 0 : _c.clear();
(_d = this._typeIds) === null || _d === void 0 ? void 0 : _d.clear();
for (const child of this.children)
child.clear();
return this;
}
}
Builder.prototype.length = 1;
Builder.prototype.stride = 1;
Builder.prototype.children = null;
Builder.prototype.finished = false;
Builder.prototype.nullValues = null;
Builder.prototype._isValid = () => true;
/** @ignore */
export class FixedWidthBuilder extends Builder {
constructor(opts) {
super(opts);
this._values = new DataBufferBuilder(new this.ArrayType(0), this.stride);
}
setValue(index, value) {
const values = this._values;
values.reserve(index - values.length + 1);
return super.setValue(index, value);
}
}
/** @ignore */
export class VariableWidthBuilder extends Builder {
constructor(opts) {
super(opts);
this._pendingLength = 0;
this._offsets = new OffsetsBufferBuilder();
}
setValue(index, value) {
const pending = this._pending || (this._pending = new Map());
const current = pending.get(index);
current && (this._pendingLength -= current.length);
this._pendingLength += (value instanceof MapRow) ? value[kKeys].length : value.length;
pending.set(index, value);
}
setValid(index, isValid) {
if (!super.setValid(index, isValid)) {
(this._pending || (this._pending = new Map())).set(index, undefined);
return false;
}
return true;
}
clear() {
this._pendingLength = 0;
this._pending = undefined;
return super.clear();
}
flush() {
this._flush();
return super.flush();
}
finish() {
this._flush();
return super.finish();
}
_flush() {
const pending = this._pending;
const pendingLength = this._pendingLength;
this._pendingLength = 0;
this._pending = undefined;
if (pending && pending.size > 0) {
this._flushPending(pending, pendingLength);
}
return this;
}
}
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