TemporalQueries Class

Definition

[Android.Runtime.Register("java/time/temporal/TemporalQueries", ApiSince=26, DoNotGenerateAcw=true)]
public sealed class TemporalQueries : Java.Lang.Object

[<Android.Runtime.Register("java/time/temporal/TemporalQueries", ApiSince=26, DoNotGenerateAcw=true)>]
type TemporalQueries = class
    inherit Object

Inheritance

Object

Object

TemporalQueries

Attributes

RegisterAttribute

Remarks

Common implementations of TemporalQuery.

This class provides common implementations of TemporalQuery. These are defined here as they must be constants, and the definition of lambdas does not guarantee that. By assigning them once here, they become 'normal' Java constants.

Queries are a key tool for extracting information from temporal objects. They exist to externalize the process of querying, permitting different approaches, as per the strategy design pattern. Examples might be a query that checks if the date is the day before February 29th in a leap year, or calculates the number of days to your next birthday.

The TemporalField interface provides another mechanism for querying temporal objects. That interface is limited to returning a long. By contrast, queries can return any type.

There are two equivalent ways of using a TemporalQuery. The first is to invoke the method on this interface directly. The second is to use TemporalAccessor#query(TemporalQuery):

// these two lines are equivalent, but the second approach is recommended
              temporal = thisQuery.queryFrom(temporal);
              temporal = temporal.query(thisQuery);

It is recommended to use the second approach, query(TemporalQuery), as it is a lot clearer to read in code.

The most common implementations are method references, such as LocalDate::from and ZoneId::from. Additional common queries are provided to return: <ul> <li> a Chronology, <li> a LocalDate, <li> a LocalTime, <li> a ZoneOffset, <li> a precision, <li> a zone, or <li> a zoneId. </ul>

Added in 1.8.

Java documentation for java.time.temporal.TemporalQueries.

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Properties

Methods

Explicit Interface Implementations

Extension Methods

Applies to