Package com.github.collinalpert.java2db.utilities

Class IoC

java.lang.Object

com.github.collinalpert.java2db.utilities.IoC

public class IoC
extends java.lang.Object

Author:

Collin Alpert

A

Inversion of Control

class. It is responsible for registering services, resolving services and administrating default query constraints.

Constructor Summary

Constructors

Constructor	Description
IoC()

Method Summary

Modifier and Type	Method	Description
static <E extends BaseEntity> void	addConstraint(java.lang.Class<E> clazz, SqlPredicate<E> predicate)	Adds a query constraint to a query made with a certain entity.
<E extends BaseEntity,S extends BaseService<E>> boolean	isRegistered(java.lang.Class<S> clazz)	Checks if a service has already been registered.
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> E	resolve(java.lang.Class<E> clazz)	Resolves any class.
static <E extends BaseEntity,S extends BaseService<E>> 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.

Methods inherited from class java.lang.Object

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

Constructor Detail

IoC

public IoC()

Method Detail

resolve

public static <E> E resolve(java.lang.Class<E> clazz)

Resolves any class.

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 <E extends BaseEntity,S extends BaseService<E>> S resolveService(java.lang.Class<S> clazz)

Resolves a service class. This is to prevent multiple instances of a service. Only one is needed in the lifecycle of an application.

Type Parameters:

E - The type of the service class's entity.

S - The type of the service class.

Parameters:

clazz - The service class to retrieve.

Returns:

The previously registered instance of a service class.

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.

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.

addConstraint

public static <E extends BaseEntity> void addConstraint(java.lang.Class<E> clazz,
                                                        SqlPredicate<E> predicate)

Adds a query constraint to a query made with a certain entity. This means that any query made with this entity will include this predicate.

Type Parameters:

E - The type of the entity.

Parameters:

clazz - The entity to add the constraint to.

predicate - The constraint.

isRegistered

public <E extends BaseEntity,S extends BaseService<E>> boolean isRegistered(java.lang.Class<S> clazz)

Checks if a service has already been registered.

Type Parameters:

E - The type of the entity.

S - The type of the service.

Parameters:

clazz - The class os the service.

Returns:

True if an instance of the service is registered, false if not.