Class ShutdownHookProcessDestroyer

java.lang.Object
org.apache.commons.exec.ShutdownHookProcessDestroyer
All Implemented Interfaces:
Runnable, ProcessDestroyer
public class ShutdownHookProcessDestroyer extends Object implements ProcessDestroyer, Runnable
Destroys all registered Processes when the VM exits.

  • Field Details

    • processes

      private final List<Process> processes
      The list of currently running processes.

    • destroyProcessThread

      private ShutdownHookProcessDestroyer.ProcessDestroyerThread destroyProcessThread
      The thread registered at the JVM to execute the shutdown handler.

    • added

      private final AtomicBoolean added
      Whether or not this ProcessDestroyer has been registered as a shutdown hook.

    • running

      private final AtomicBoolean running
      Whether or not this ProcessDestroyer is currently running as shutdown hook.

  • Constructor Details

    • ShutdownHookProcessDestroyer

      public ShutdownHookProcessDestroyer()
      Constructs a ProcessDestroyer and obtains Runtime.addShutdownHook() and Runtime.removeShutdownHook() through reflection. The ProcessDestroyer manages a list of processes to be destroyed when the VM exits. If a process is added when the list is empty, this ProcessDestroyer is registered as a shutdown hook. If removing a process results in an empty list, the ProcessDestroyer is removed as a shutdown hook.

  • Method Details

    • add

      public boolean add(Process process)
      Returns true if the specified Process was successfully added to the list of processes to destroy upon VM exit.
      Specified by:
      add in interface ProcessDestroyer
      Parameters:
      process - the process to add.
      Returns:
      true if the specified Process was successfully added.

    • addShutdownHook

      private void addShutdownHook()
      Registers this ProcessDestroyer as a shutdown hook.

    • isAddedAsShutdownHook

      public boolean isAddedAsShutdownHook()
      Tests whether or not the ProcessDestroyer is registered as shutdown hook.
      Returns:
      true if this is currently added as shutdown hook.

    • isEmpty

      public boolean isEmpty()
      Tests emptiness (size == 0).
      Returns:
      Whether or not this is empty.
      Since:
      1.4.0

    • remove

      public boolean remove(Process process)
      Returns true if the specified Process was successfully removed from the list of processes to destroy upon VM exit.
      Specified by:
      remove in interface ProcessDestroyer
      Parameters:
      process - the process to remove.
      Returns:
      true if the specified Process was successfully removed.

    • removeShutdownHook

      private void removeShutdownHook()
      Removes this ProcessDestroyer as a shutdown hook.

    • run

      public void run()
      Invoked by the VM when it is exiting.
      Specified by:
      run in interface Runnable

    • size

      public int size()
      Returns the number of registered processes.
      Specified by:
      size in interface ProcessDestroyer
      Returns:
      the number of register process.