Gets the value of the specified field as a long.
Gets the value of the specified field as a long.
This queries the date-time for the value for the specified field. The returned value may be outside the valid range of values for the field. If the date-time cannot return the value, because the field is unsupported or for some other reason, an exception will be thrown.
Implementations must check and handle all fields defined in ChronoField.
If the field is supported, then the value of the field must be returned.
If unsupported, then a DateTimeException must be thrown.
If the field is not a ChronoField, then the result of this method
is obtained by invoking TemporalField.getFrom(TemporalAccessor)
passing this as the argument.
Implementations must not alter either this object.
the field to get, not null
the value for the field
if numeric overflow occurs
DateTimeExceptionif a value for the field cannot be obtained
Checks if the specified field is supported.
Checks if the specified field is supported.
This checks if the date-time can be queried for the specified field.
If false, then calling the #range(TemporalField) range and #get(TemporalField) get
methods will throw an exception.
Implementations must check and handle all fields defined in ChronoField.
If the field is supported, then true is returned, otherwise false
If the field is not a ChronoField, then the result of this method
is obtained by invoking TemporalField.isSupportedBy(TemporalAccessor)
passing this as the argument.
Implementations must not alter this object.
the field to check, null returns false
true if this date-time can be queried for the field, false if not
Gets the value of the specified field as an int.
Gets the value of the specified field as an int.
This queries the date-time for the value for the specified field. The returned value will always be within the valid range of values for the field. If the date-time cannot return the value, because the field is unsupported or for some other reason, an exception will be thrown.
Implementations must check and handle all fields defined in ChronoField.
If the field is supported and has an int range, then the value of
the field must be returned.
If unsupported, then a DateTimeException must be thrown.
If the field is not a ChronoField, then the result of this method
is obtained by invoking TemporalField.getFrom(TemporalAccessor)
passing this as the argument.
Implementations must not alter either this object.
the field to get, not null
the value for the field, within the valid range of values
if numeric overflow occurs
DateTimeExceptionif the value is outside the range of valid values for the field
Queries this date-time.
Queries this date-time.
This queries this date-time using the specified query strategy object.
Queries are a key tool for extracting information from date-times. They exists 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 most common query implementations are method references, such as
LocalDate::from and ZoneId::from.
Further implementations are on TemporalQueries.
Queries may also be defined by applications.
Implementations of this method must behave as follows:
public <R> R query(TemporalQuery<R> type) {
// only include an if statement if the implementation can return it
if (query == TemporalQueries.zoneId()) return // the ZoneId
if (query == TemporalQueries.chronology()) return // the Chrono
if (query == TemporalQueries.precision()) return // the precision
// call default method
return super.query(query);
}
the type of the result
the query to invoke, not null
the query result, null may be returned (defined by the query)
if numeric overflow occurs
DateTimeExceptionif unable to query
Gets the range of valid values for the specified field.
Gets the range of valid values for the specified field.
All fields can be expressed as a long integer.
This method returns an object that describes the valid range for that value.
The value of this temporal object is used to enhance the accuracy of the returned range.
If the date-time cannot return the range, because the field is unsupported or for
some other reason, an exception will be thrown.
Note that the result only describes the minimum and maximum valid values and it is important not to read too much into them. For example, there could be values within the range that are invalid for the field.
Implementations must check and handle all fields defined in ChronoField.
If the field is supported, then the range of the field must be returned.
If unsupported, then a DateTimeException must be thrown.
If the field is not a ChronoField, then the result of this method
is obtained by invoking TemporalField.rangeRefinedBy(TemporalAccessorl)
passing this as the argument.
Implementations must not alter either this object.
the field to query the range for, not null
the range of valid values for the field, not null
if the range for the field cannot be obtained
Framework-level interface defining read-only access to a temporal object, such as a date, time, offset or some combination of these.
This is the base interface type for date, time and offset objects. It is implemented by those classes that can provide information as
TemporalField fieldsorTemporalQuery queries.Most date and time information can be represented as a number. These are modeled using
TemporalFieldwith the number held using alongto handle large values. Year, month and day-of-month are simple examples of fields, but they also include instant and offsets. SeeChronoFieldfor the standard set of fields.Two pieces of date/time information cannot be represented by numbers, the
Chronology chronologyand theZoneId time-zone. These can be accessed via#query(TemporalQuery) queriesusing the static methods defined onTemporalQueries.A sub-interface,
Temporal, extends this definition to one that also supports adjustment and manipulation on more complete temporal objects.This interface is a framework-level interface that should not be widely used in application code. Instead, applications should create and pass around instances of concrete types, such as
LocalDate. There are many reasons for this, part of which is that implementations of this interface may be in calendar systems other than ISO. SeeChronoLocalDatefor a fuller discussion of the issues.Specification for implementors
This interface places no restrictions on the mutability of implementations, however immutability is strongly recommended.