Package org.apache.commons.daemon.support

Class DaemonWrapper

  • All Implemented Interfaces:
    Daemon
    public class DaemonWrapper
extends Object
implements Daemon
    Implementation of the Daemon that allows running standard applications as daemons. The applications must have the mechanism to manage the application lifecycle.

    • Constructor Detail

      • DaemonWrapper

        public DaemonWrapper()
        Constructs a new initialized instance.

    • Method Detail

      • init

        public void init​(DaemonContext context)
          throws Exception
        Called from DaemonLoader on init stage.

        Accepts the following configuration arguments:

        • -daemon-properties: - load DaemonConfiguration properties from the specified file to act as defaults
        • -start: set start class name
        • -start-method: set start method name
        • -stop: set stop class name
        • -stop-method: set stop method name
        • -stop-argument: set optional argument to stop method
        • Anything else is treated as a startup argument

        The following "-daemon-properties" are recognized:

        • args (startup argument)
        • start
        • start.method
        • stop
        • stop.method
        • stop.args
        These are used to set the corresponding item if it has not already been set by the command arguments. However, note that args and stop.args are appended to any existing values.
        Specified by:
        init in interface Daemon
        Parameters:
        context - A DaemonContext object used to communicate with the container.
        Throws:
        DaemonInitException - An exception that prevented initialization where you want to display a nice message to the user, rather than a stack trace.
        Exception - Any exception preventing a successful initialization.

      • start

        public void start()
           throws Exception
        Description copied from interface: Daemon
        Starts the operation of this Daemon instance. This method is to be invoked by the environment after the init() method has been successfully invoked and possibly the security level of the JVM has been dropped. Implementors of this method are free to start any number of threads, but need to return control after having done that to enable invocation of the stop()-method.
        Specified by:
        start in interface Daemon
        Throws:
        Exception - If the start was not successful

      • stop

        public void stop()
          throws Exception
        Description copied from interface: Daemon
        Stops the operation of this Daemon instance. Note that the proper place to free any allocated resources such as sockets or file descriptors is in the destroy method, as the container may restart the Daemon by calling start() after stop().
        Specified by:
        stop in interface Daemon
        Throws:
        Exception - If the stop was not successful

      • destroy

        public void destroy()
        Description copied from interface: Daemon
        Frees any resources allocated by this daemon such as file descriptors or sockets. This method gets called by the container after stop() has been called, before the JVM exits. The Daemon cannot be restarted after this method has been called without a new call to the init() method.
        Specified by:
        destroy in interface Daemon