Summary

Add a suggestion for using java.time.DateTimeFormatter instead of java.text.DateFormat/java.text.SimpleDateFormat.

Problem

The Synchronization section in both DateFormat and SimpleDateFormat does not suggest a better alternative.

Solution

Add an API note to use DateTimeFormatter as an alternative in both class descriptions.

Specification

In the class descriptions of java.text.DateFormat and java.text.SimpleDateFormat classes,

Change the following paragraphs from:

 * Date formats are not synchronized.
 * It is recommended to create separate format instances for each thread.
 * If multiple threads access a format concurrently, it must be synchronized
 * externally.

to:

 * Date formats are not synchronized.
 * It is recommended to create separate format instances for each thread.
 * If multiple threads access a format concurrently, it must be synchronized
 * externally.
 * @apiNote Consider using {@link java.time.format.DateTimeFormatter} as an
 * immutable and thread-safe alternative.

Add the following @see tag:

 * @see          java.time.format.DateTimeFormatter