/*
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* @copyright (c) 2016, Philipp Thürwächter & Pattrick Hüper
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* @copyright (c) 2007-present, Stephen Colebourne & Michael Nascimento Santos
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* @license BSD-3-Clause (see LICENSE in the root directory of this source tree)
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*/
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import { abstractMethodFail } from '../assert';
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import { Enum } from '../Enum';
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/**
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* Strategy for querying a temporal object.
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*
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* Queries are a key tool for extracting information from temporal objects.
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* They exist to externalize the process of querying, permitting different
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* approaches, as per the strategy design pattern.
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* Examples might be a query that checks if the date is the day before February 29th
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* in a leap year, or calculates the number of days to your next birthday.
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*
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* The {@link TemporalField} interface provides another mechanism for querying
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* temporal objects. That interface is limited to returning a `long`.
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* By contrast, queries can return any type.
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*
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* There are two equivalent ways of using a {@link TemporalQuery}.
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* The first is to invoke the method on this interface directly.
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* The second is to use {@link TemporalAccessor#query}:
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* <pre>
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* // these two lines are equivalent, but the second approach is recommended
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* temporal = thisQuery.queryFrom(temporal);
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* temporal = temporal.query(thisQuery);
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* </pre>
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* It is recommended to use the second approach, {@link query},
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* as it is a lot clearer to read in code.
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*
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* The most common implementations are method references, such as
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* {@link LocalDate::from} and {@link ZoneId::from}.
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* Further implementations are on {@link TemporalQueries}.
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* Queries may also be defined by applications.
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*
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* ### Specification for implementors
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*
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* This interface places no restrictions on the mutability of implementations,
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* however immutability is strongly recommended.
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*
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* @interface
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*/
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export class TemporalQuery extends Enum {
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/**
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* Queries the specified temporal object.
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*
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* This queries the specified temporal object to return an object using the logic
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* encapsulated in the implementing class.
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* Examples might be a query that checks if the date is the day before February 29th
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* in a leap year, or calculates the number of days to your next birthday.
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*
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* There are two equivalent ways of using this method.
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* The first is to invoke this method directly.
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* The second is to use {@link TemporalAccessor#query}:
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* <pre>
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* // these two lines are equivalent, but the second approach is recommended
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* temporal = thisQuery.queryFrom(temporal);
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* temporal = temporal.query(thisQuery);
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* </pre>
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* It is recommended to use the second approach, {@link query},
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* as it is a lot clearer to read in code.
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*
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* ### Specification for implementors
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*
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* The implementation must take the input object and query it.
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* The implementation defines the logic of the query and is responsible for
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* documenting that logic.
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* It may use any method on {@link TemporalAccessor} to determine the result.
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* The input object must not be altered.
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*
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* The input temporal object may be in a calendar system other than ISO.
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* Implementations may choose to document compatibility with other calendar systems,
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* or reject non-ISO temporal objects by querying the chronology (see {@link TemporalQueries#chronology}).
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*
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* This method may be called from multiple threads in parallel.
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* It must be thread-safe when invoked.
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*
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* @param {TemporalAccessor} temporal the temporal object to query, not null
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* @return the queried value, may return null to indicate not found
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* @throws DateTimeException if unable to query
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* @throws ArithmeticException if numeric overflow occurs
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*/
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// eslint-disable-next-line no-unused-vars
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queryFrom(temporal){
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abstractMethodFail('queryFrom');
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}
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}
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/**
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* @private
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*
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* Factory to create something similar to the JSR-310 {TemporalQuery} interface, takes a function and returns a new TemporalQuery object that presents that function
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* as the queryFrom() function.
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* @param name for the underlying Enum
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* @param queryFromFunction
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*/
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export function createTemporalQuery(name, queryFromFunction) {
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class ExtendedTemporalQuery extends TemporalQuery {
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}
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ExtendedTemporalQuery.prototype.queryFrom = queryFromFunction;
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return new ExtendedTemporalQuery(name);
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}
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