Package de.gebit.integrity.runner.forking

Class DefaultForker

  • All Implemented Interfaces:
    Forker
    public class DefaultForker
extends Object
implements Forker
    A default forking implementation. This should be suitable for most execution environments. If not, it is designed to be easily extensible, or alternatively you can of course create an entirely own Forker implementation.

    This default forker does effectively create a "mirror" of the current process, runnning the same main class with the same arguments as the main process. It therefore does not accept any parameters (= it does not have a constructor with parameters), since there is no need to do that. However, if you want to create a forker that modifies this behavior, you may very well subclass this one or create one from scratch. You may also use a constructor with parameters (use ForkerParameter just like you would for fixture methods) if you want to parameterize your forker in the test scripts.

    Author:
    Rene Schneider - initial API and implementation

    • Constructor Detail

      • DefaultForker

        public DefaultForker()

    • Method Detail

      • fork

        public ForkedProcess fork​(String[] someCommandLineArguments,
                          String aForkName,
                          long aRandomSeed,
                          TimeSyncState aTimeSyncState)
                   throws ForkException
        Description copied from interface: Forker
        Performs the actual forking.
        Specified by:
        fork in interface Forker
        Parameters:
        someCommandLineArguments - the original command line arguments given to the JVM of the parent process
        aForkName - the name of the fork
        aRandomSeed - the seed for the RNG of the fork
        aTimeSyncState - time synchronization state info for this particular fork (will be provided just in case the forker wants to do something with it - time synchronization also happens right after the connection to the fork was established by the master) or null if no test time sync state is to be set
        Returns:
        the newly created process
        Throws:
        ForkException - if something goes wrong

      • createArgumentList

        protected List<String> createArgumentList​(String[] someCommandLineArguments,
                                          String aForkName,
                                          long aRandomSeed,
                                          TimeSyncState aTimeSyncState)
        Creates the argument list used to fork the process.
        Parameters:
        someCommandLineArguments - the command line arguments provided to #fork(String[], int, String).
        aForkName - the name for the new fork
        aRandomSeed - the seed for the RNG of the fork
        aTimeSyncState - time synchronization state info for this particular fork (will be provided just in case the forker or fork wants to do something with it - time synchronization also happens right after the connection to the fork was established by the master) or null if no test time sync state is to be set
        Returns:
        the argument list

      • addJavaExecutable

        protected void addJavaExecutable​(List<String> anArgumentList)
        Adds the name of the java executable to the argument list provided. Default implementation tries to determine this using the system property "java.home".
        Parameters:
        anArgumentList - the argument list to extend

      • addClassPath

        protected void addClassPath​(List<String> anArgumentList)
        Adds the classpath parameter to the argument list. Default implementation uses the system property "java.class.path".
        Parameters:
        anArgumentList - the argument list to extend

      • addForkInformation

        protected void addForkInformation​(List<String> anArgumentList,
                                  String aForkName,
                                  long aRandomSeed,
                                  TimeSyncState aTimeSyncState)
        Adds the system property definitions telling the fork on which port it should listen and which name it has.
        Parameters:
        anArgumentList - the argument list to extend
        aForkName - the name for the fork
        aRandomSeed - the seed for the RNG of the fork
        aTimeSyncState - time synchronization state info for this particular fork (will be provided just in case the fork wants to do something with it - time synchronization also happens right after the connection to the fork was established by the master) or null if no test time sync state is to be provided

      • addTimeSyncInformation

        protected void addTimeSyncInformation​(List<String> anArgumentList,
                                      TimeSyncState aTimeSyncState)
        Adds time sync information, if provided for this fork.
        Parameters:
        anArgumentList - the argument list to extend
        aTimeSyncState - time synchronization state info for this particular fork (will be provided just in case the fork wants to do something with it - time synchronization also happens right after the connection to the fork was established by the master) or null if no test time sync state is to be provided

      • getForkHost

        protected String getForkHost()
        The host name / IP to which the fork should be bound.
        Returns:

      • getForkPort

        protected Integer getForkPort()
        The port to which the fork should be bound.
        Returns:

      • addJVMArguments

        protected void addJVMArguments​(List<String> anArgumentList)
        Adds any random JVM configuration arguments to the argument list. Default implementation asks the RuntimeMXBean.
        Parameters:
        anArgumentList - the argument list to extend

      • addClassName

        protected void addClassName​(List<String> anArgumentList)
        Adds the name of the main class to the argument list. Default implementation uses guessMainClassName() to search stack traces for the class.
        Parameters:
        anArgumentList - the argument list to extend

      • addApplicationArguments

        protected void addApplicationArguments​(List<String> anArgumentList,
                                       String[] someCommandLineArguments)
        Adds the application-specific arguments to the argument list.
        Parameters:
        anArgumentList - the argument list to extend
        someCommandLineArguments - the applications' arguments, as provided to Integrity

      • guessMainClassName

        protected String guessMainClassName()
        Tries to determine the fully qualified name of the main class, since you cannot ask the JVM for it unfortunately.
        Returns:
        the name of the main class