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javamultithreadinglifecyclemain-method

Java app lifecycle

When does a typical Java app finish?

If I start a new thread in the main method and then the main method finishes, but the other thread continues working, the app would still be on until all it's threads have died, wouldn't it?

Thanks & Merry Christmas!

Solution

  • Yes, unless it's a deamon thread. Quoting from Thread API:

    When a Java Virtual Machine starts up, there is usually a single non-daemon thread (which typically calls the method named main of some designated class). The Java Virtual Machine continues to execute threads until either of the following occurs:

    • The exit method of class Runtime has been called and the security manager has permitted the exit operation to take place.
    • All threads that are not daemon threads have died, either by returning from the call to the run method or by throwing an exception that propagates beyond the run method.