The Java Tutorials have been written for JDK 8. Examples and practices described in this page don't take advantage of improvements introduced in later releases and might use technology no longer available.
See Java Language Changes for a summary of updated language features in Java SE 9 and subsequent releases.
See JDK Release Notes for information about new features, enhancements, and removed or deprecated options for all JDK releases.
The Date-Time API offers a rich set of methods within a rich set of classes. The method names are made consistent between classes wherever possible. For example, many of the classes offer a now method that captures the date or time values of the current moment that are relevant to that class. There are from methods that allow conversion from one class to another.
There is also standardization regarding the method name prefixes. Because most of the classes in the Date-Time API are immutable, the API does not include set methods. (After its creation, the value of an immutable object cannot be changed. The immutable equivalent of a set method is with.) The following table lists the commonly used prefixes:
Prefix | Method Type | Use |
---|---|---|
of | static factory | Creates an instance where the factory is primarily validating the input parameters, not converting them. |
from | static factory | Converts the input parameters to an instance of the target class, which may involve losing information from the input. |
parse | static factory | Parses the input string to produce an instance of the target class. |
format | instance | Uses the specified formatter to format the values in the temporal object to produce a string. |
get | instance | Returns a part of the state of the target object. |
is | instance | Queries the state of the target object. |
with | instance | Returns a copy of the target object with one element changed; this is the immutable equivalent to a set method on a JavaBean. |
plus | instance | Returns a copy of the target object with an amount of time added. |
minus | instance | Returns a copy of the target object with an amount of time subtracted. |
to | instance | Converts this object to another type. |
at | instance | Combines this object with another. |