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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; | |
| } | |
| } | |
| //# sourceMappingURL=builder.mjs.map | |