This is the base interface type for date, time and offset objects. It is implemented by those classes that can provide information as fields or queries.
Most date and time information can be represented as a number.
These are modeled using TemporalField with the number held using
a long to handle large values. Year, month and day-of-month are
simple examples of fields, but they also include instant and offsets.
See ChronoField for the standard set of fields.
Two pieces of date/time information cannot be represented by numbers,
the chronology and the
time-zone.
These can be accessed via queries using
the static methods defined on TemporalQuery.
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.
See java. for a fuller discussion of the issues.
Implementation Specification
This interface places no restrictions on the mutability of implementations, however immutability is strongly recommended.
| Modifier and Type | Method and Description |
|---|---|
| public default int | Returns: the value for the field, within the valid range of valuesthe field to get, not null field)Gets the value of the specified field as an |
| public long | Returns: the value for the fieldthe field to get, not null field)Gets the value of the specified field as a |
| public boolean | Returns: true if this date-time can be queried for the field, false if notthe field to check, null returns false field)Checks if the specified field is supported. |
| public default < the type of the result R> R | Returns: the query result, null may be returned (defined by the query)the query to invoke, not null query)Queries this date-time. |
| public default ValueRange | Returns: the range of valid values for the field, not nullthe field to query the range for, not null field)Gets the range of valid values for the specified field. |
| get | back to summary |
|---|---|
| public default int get(TemporalField field) Gets the value of the specified field as an This queries the date-time for the value of 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. Implementation Specification Implementations must check and handle all fields defined in
If the field is not a Implementations must ensure that no observable state is altered when this read-only method is invoked. The default implementation must behave equivalent to this code:
if (range(field).isIntValue()) {
return range(field).checkValidIntValue(getLong(field), field);
}
throw new UnsupportedTemporalTypeException("Invalid field " + field + " + for get() method, use getLong() instead");
| |
| getLong | back to summary |
|---|---|
| public long getLong(TemporalField field) Gets the value of the specified field as a This queries the date-time for the value of 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. Implementation Specification Implementations must check and handle all fields defined in
If the field is not a Implementations must ensure that no observable state is altered when this read-only method is invoked.
| |
| isSupported | back to summary |
|---|---|
| public boolean isSupported(TemporalField field) 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 Implementation Specification Implementations must check and handle all fields defined in
If the field is not a Implementations must ensure that no observable state is altered when this read-only method is invoked.
| |
| query | back to summary |
|---|---|
| public default <R> R query(TemporalQuery<R> query) 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
Implementation Specification The default implementation must behave equivalent to this code:
if (query == TemporalQueries.zoneId() ||
query == TemporalQueries.chronology() || query == TemporalQueries.precision()) {
return null;
}
return query.queryFrom(this);
Future versions are permitted to add further queries to the if statement.
All classes implementing this interface and overriding this method must call
If the implementation can supply a value for one of the queries listed in the
if statement of the default implementation, then it must do so.
For example, an application-defined
if (query == TemporalQueries.precision()) {
return MINUTES;
}
return TemporalAccessor.super.query(query);
Implementations must ensure that no observable state is altered when this read-only method is invoked.
| |
| range | back to summary |
|---|---|
| public default ValueRange range(TemporalField field) Gets the range of valid values for the specified field.
All fields can be expressed as a 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. Implementation Specification Implementations must check and handle all fields defined in
If the field is not a Implementations must ensure that no observable state is altered when this read-only method is invoked. The default implementation must behave equivalent to this code:
if (field instanceof ChronoField) {
if (isSupported(field)) {
return field.range();
}
throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
}
return field.rangeRefinedBy(this);
| |
