Class Main


  • public class Main
    extends Object
    • Field Summary

      Fields 
      Modifier and Type Field Description
      static String persistenceUnitName
      This name will be used to configure the EntityManagerFactory based on the corresponding name in the META-INF/persistence.xml file
    • Constructor Summary

      Constructors 
      Constructor Description
      Main()  
    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static javax.persistence.EntityManager getEM()
      Creates a new EntityManager from the EntityManagerFactory.
      static javax.persistence.EntityManagerFactory getFactory()
      Initializes the EntityManagerFactory using the System properties.
      static int getMyPid()
      Finds the process id of the UNIX process for this application.
      static javax.persistence.EntityManager getNewEM()  
      static void memory()
      Reports memory use
      static void memory​(String title)
      Reports memory use
      static String memoryInfo​(String title, boolean doGc)  
      static void persistObjects​(Object... v)
      See also https://download.oracle.com/otn-pub/jcp/persistence-2_1-fr-eval-spec/JavaPersistence.pdf, which says (in "3.2.2 Persisting an Entity Instance"): If X is a new entity, it becomes managed.
      static <T> void saveObject​(T o)  
    • Field Detail

      • persistenceUnitName

        public static final String persistenceUnitName
        This name will be used to configure the EntityManagerFactory based on the corresponding name in the META-INF/persistence.xml file
        See Also:
        Constant Field Values
    • Constructor Detail

      • Main

        public Main()
    • Method Detail

      • getMyPid

        public static int getMyPid()
        Finds the process id of the UNIX process for this application. FIXME: This obviously is non-portable outside of UNIX.
        Returns:
        PID, or -1 on failure
      • getFactory

        public static javax.persistence.EntityManagerFactory getFactory()
        Initializes the EntityManagerFactory using the System properties. The "icd" name will be used to configure based on the corresponding name in the META-INF/persistence.xml file
      • getEM

        public static javax.persistence.EntityManager getEM()
        Creates a new EntityManager from the EntityManagerFactory.
      • getNewEM

        public static javax.persistence.EntityManager getNewEM()
      • memory

        public static void memory()
        Reports memory use
      • memory

        public static void memory​(String title)
        Reports memory use
      • memoryInfo

        public static String memoryInfo​(String title,
                                        boolean doGc)
      • persistObjects

        public static void persistObjects​(Object... v)
        See also https://download.oracle.com/otn-pub/jcp/persistence-2_1-fr-eval-spec/JavaPersistence.pdf, which says (in "3.2.2 Persisting an Entity Instance"):
        • If X is a new entity, it becomes managed. The entity X will be entered into the database at or before transaction commit or as a result of the flush operation.
        • If X is a preexisting managed entity, it is ignored by the persist operation (...)
        • If X is a detached object, the EntityExistsException may be thrown when the persist operation is invoked, or the EntityExistsException or another PersistenceException may be thrown at flush or commit time
      • saveObject

        public static <T> void saveObject​(T o)
        Parameters:
        o - a detached object