Package com.github.collinalpert.java2db.utilities

Class IoC

java.lang.Object
com.github.collinalpert.java2db.utilities.IoC
public final class IoC
extends java.lang.Object
An 
Inversion of Control
container. It is responsible for registering and resolving services and custom mappers.
Author:
Collin Alpert

  • Constructor Summary

    Constructors 
    Constructor Description
    IoC()  

  • Method Summary

    Modifier and Type Method Description
    static <E> E createInstance​(java.lang.Class<E> clazz)
    Creates an instance of any class with an empty constructor.
    static <E extends BaseEntity>
    boolean    		 isMapperRegistered​(java.lang.Class<E> clazz)
    Checks if a mapper has already been registered.
    static <E extends BaseEntity>
    boolean    		 isServiceRegistered​(java.lang.Class<E> clazz)
    Checks if a service has already been registered.
    static <E extends BaseEntity,​ M extends Mappable<E>>
    void    		 registerMapper​(java.lang.Class<E> clazz, M mapper)
    Registers an instance of a mapper class.
    static <E extends BaseEntity,​ S extends BaseService<E>>
    void    		 registerService​(java.lang.Class<E> clazz, S service)
    Registers an instance of a service class.
    static <E extends BaseEntity>
    Mappable<E>    		 resolveMapper​(java.lang.Class<E> clazz)
    Resolves a mapper class.
    static <E extends BaseEntity>
    Mappable<E>    		 resolveMapper​(java.lang.Class<E> clazz, Mappable<E> defaultMapper)
    Resolves a mapper class.
    static <S extends BaseService>
    S    		 resolveService​(java.lang.Class<S> clazz)
    Resolves a service class.
    static <E extends BaseEntity,​ S extends BaseService<E>>
    S    		 resolveServiceByEntity​(java.lang.Class<E> clazz)
    Resolves a service class by the entity it was registered with.
    static <E extends BaseEntity,​ S extends BaseService<E>>
    S    		 resolveServiceByEntity​(java.lang.Class<E> clazz, S defaultService)
    Resolves a service class by the entity it was registered with.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • IoC

      public IoC()

  • Method Details

    • createInstance

      public static <E> E createInstance​(java.lang.Class<E> clazz)
      Creates an instance of any class with an empty constructor. It is used to create a new instance of the entity classes, so they can be filled with values. This is why every entity class needs an empty constructor.
      Type Parameters:
      E - The type of the entity.
      Parameters:
      clazz - The class to be constructed.
      Returns:
      An instance of this class.
      Throws:
      java.lang.IllegalArgumentException - if the class cannot be constructed for any reason. This can occur if there is no public parameterless constructor available.

    • resolveService

      public static <S extends BaseService> S resolveService​(java.lang.Class<S> clazz)
      Resolves a service class. This is to preserve the singleton pattern. Only one instance of a service is needed in the lifecycle of an application.
      Type Parameters:
      S - The type of the service class.
      Parameters:
      clazz - The service class to retrieve.
      Returns:
      The previously registered instance of a service class.

    • resolveMapper

      public static <E extends BaseEntity> Mappable<E> resolveMapper​(java.lang.Class<E> clazz)
      Resolves a mapper class. This is to preserve the singleton pattern. Only one instance of a mapper is needed in the lifecycle of an application.
      Type Parameters:
      E - The type of the entity.
      Parameters:
      clazz - The entity that the mapper was registered for.
      Returns:
      The previously registered instance of a service class.

    • resolveMapper

      public static <E extends BaseEntity> Mappable<E> resolveMapper​(java.lang.Class<E> clazz, Mappable<E> defaultMapper)
      Resolves a mapper class. If an instance of this mapper has not been registered yet, a backup mapper is used and also registered.
      Type Parameters:
      E - The type of the mapper.
      Parameters:
      clazz - The type of the corresponding mapper.
      defaultMapper - The default mapper, in case a custom mapper is not registered for this type.
      Returns:
      The mapper for the entity. If is does not exists, the default mapper is returned.

    • resolveServiceByEntity

      public static <E extends BaseEntity,​ S extends BaseService<E>> S resolveServiceByEntity​(java.lang.Class<E> clazz)
      Resolves a service class by the entity it was registered with.
      Type Parameters:
      E - The type of the entity.
      S - The type of the service.
      Parameters:
      clazz - The entity class corresponding to a service class.
      Returns:
      An instance of a previously registered service class.

    • resolveServiceByEntity

      public static <E extends BaseEntity,​ S extends BaseService<E>> S resolveServiceByEntity​(java.lang.Class<E> clazz, S defaultService)
      Resolves a service class by the entity it was registered with. If an instance of this service has not been registered yet, a backup service is used and also registered.
      Type Parameters:
      E - The type of the entity.
      S - The type of the service.
      Parameters:
      clazz - The entity class corresponding to a service class.
      defaultService - The backup to use in case a service for the supplied class has not been registered yet.
      Returns:
      An instance of a previously registered service class.

    • registerService

      public static <E extends BaseEntity,​ S extends BaseService<E>> void registerService​(java.lang.Class<E> clazz, S service)
      Registers an instance of a service class.
      Type Parameters:
      E - The type of the entity.
      S - The type of the service class.
      Parameters:
      clazz - An entity class.
      service - The service class this entity corresponds to.

    • registerMapper

      public static <E extends BaseEntity,​ M extends Mappable<E>> void registerMapper​(java.lang.Class<E> clazz, M mapper)
      Registers an instance of a mapper class.
      Type Parameters:
      E - The type of the entity.
      M - The type of the mapper class.
      Parameters:
      clazz - An entity class.
      mapper - The mapper class for the entity.

    • isServiceRegistered

      public static <E extends BaseEntity> boolean isServiceRegistered​(java.lang.Class<E> clazz)
      Checks if a service has already been registered.
      Type Parameters:
      E - The type of the service.
      Parameters:
      clazz - The class of the entity a service was registered for.
      Returns:
      True if an instance of the service is registered, false if not.

    • isMapperRegistered

      public static <E extends BaseEntity> boolean isMapperRegistered​(java.lang.Class<E> clazz)
      Checks if a mapper has already been registered.
      Type Parameters:
      E - The type of the entity.
      Parameters:
      clazz - The class of the entity a mapper was registered for.
      Returns:
      True if an instance of the mapper is registered, false if not.