java-User (foreground) thread and daemon (background) thread

1. Daemon (background) threads Daemon Thread

The role of the daemon is to facilitate the operation of other threads, such as a garbage collection thread that is a daemon thread

A. Child threads created by the daemon thread are also daemon threads

B. You can set the thread as the daemon thread (Setdaemon (Boolean on)), but you must throw the exception before calling the Start method.

C. Do not assume that all applications can be assigned to daemon for service, such as read-write operations or computational logic.

Because once all the user threads have finished executing, the virtual machine exits, and the daemon thread is forced to exit.

2. User (foreground) thread

java-User (foreground) thread and daemon (background) thread