Hibernate ORM - hibernate-core 6.4.4.Final · org.hibernate.boot.registry.selector.spi.StrategySelector

Service which acts as a registry for named strategy implementations.

Strategies are more open-ended than services, though a strategy managed here might very well also be a service. The strategy is any interface that has multiple, (possibly short) named implementations.

StrategySelector manages resolution of particular implementation by (possibly short) name via the selectStrategyImplementor method, which is the main contract here. As indicated in the docs of that method the given name might be either a short registered name or the implementation FQN. As an example, consider resolving the org.hibernate.resource.transaction.spi.TransactionCoordinatorBuilder implementation to use. To use the JDBC-based TransactionCoordinatorBuilder the passed name might be either "jdbc" or "org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorBuilderImpl".

Strategy implementations can be managed by registerStrategyImplementor and unRegisterStrategyImplementor. Originally designed to help the OSGi use case, though no longer used there.

The service also exposes a general typing API via resolveStrategy and resolveDefaultableStrategy which accept implementation references rather than implementation names, allowing for a multitude of interpretations of said "implementation reference". See the docs for resolveDefaultableStrategy for details.

Method Summary

Modifier and Type	Method and Description
public <T> Collection<Class<? extends T>>	Returns: The implementors. Should never return `null` getRegisteredStrategyImplementors(Class<T> strategy) Retrieve all of the registered implementors of the given strategy.
public < The type of the strategy. Used to make sure that the strategy and implementation are type compatible. T> void	registerStrategyImplementor(Class<T> The strategy contract. strategy, String The registration name name, Class<? extends T> The implementation Class implementation) Registers a named implementor of a particular strategy contract.
public < The type of the strategy. Used to make sure that the strategy and implementation are type compatible. T> T	Returns: The strategy instance resolveDefaultableStrategy(Class<T> The type (interface) of the strategy to be resolved. strategy, Object The reference to the strategy for which we need to resolve an instance. strategyReference, T THe default value to use if strategyReference is null defaultValue) Resolve strategy instances.
public < The type of the strategy. Used to make sure that the strategy and implementation are type compatible. T> T	Returns: The strategy instance resolveDefaultableStrategy(Class<T> The type (interface) of the strategy to be resolved. strategy, Object The reference to the strategy for which we need to resolve an instance. strategyReference, Callable<T> A strategy for resolving the default value strategyReference resolves to null. defaultResolver) Resolve strategy instances.
public < The type of the strategy. Used to make sure that the strategy and implementation are type compatible. T> T	Returns: The strategy instance resolveStrategy(Class<T> The type (interface) of the strategy to be resolved. strategy, @Nullable Object The reference to the strategy for which we need to resolve an instance. strategyReference) Resolve strategy instances.
public <T> T	resolveStrategy(Class<T> strategy, Object strategyReference, Callable<T> defaultResolver, StrategyCreator<T> creator)
public <T> T	resolveStrategy(Class<T> strategy, Object strategyReference, T defaultValue, StrategyCreator<T> creator)
public < The type of the strategy. Used to make sure that the strategy and implementation are type compatible. T> Class<? extends T>	Returns: The named strategy implementation class. selectStrategyImplementor(Class<T> The type of strategy to be resolved. strategy, String The name of the strategy to locate; might be either a registered name or the implementation FQN. name) Locate the named strategy implementation.
public < The type of the strategy. Used to make sure that the strategy and implementation are type compatible. T> void	unRegisterStrategyImplementor(Class<T> The strategy contract. strategy, Class<? extends T> The implementation Class implementation) Un-registers a named implementor of a particular strategy contract.

Method Detail

getRegisteredStrategyImplementors back to summary

getRegisteredStrategyImplementors	back to summary
public <T> Collection<Class<? extends T>> getRegisteredStrategyImplementors(Class<T> strategy) Retrieve all of the registered implementors of the given strategy. Useful to allow defaulting the choice to the single registered implementor when only one is registered Returns:Collection<Class<? extends T>> The implementors. Should never return `null`

public <T> Collection<Class<? extends T>> getRegisteredStrategyImplementors(Class<T> strategy)

Retrieve all of the registered implementors of the given strategy. Useful to allow defaulting the choice to the single registered implementor when only one is registered

Returns:Collection<Class<? extends T>>: The implementors. Should never return null

registerStrategyImplementor	back to summary
public <T> void registerStrategyImplementor(Class<T> strategy, String name, Class<? extends T> implementation) Registers a named implementor of a particular strategy contract. Parameters <T> The type of the strategy. Used to make sure that the strategy and implementation are type compatible. strategy:Class<T> The strategy contract. name:String The registration name implementation:Class<? extends T> The implementation Class

registerStrategyImplementor

back to summary

public <T> void registerStrategyImplementor(Class<T> strategy, String name, Class<? extends T> implementation)

Registers a named implementor of a particular strategy contract.

Parameters

<T>: The type of the strategy. Used to make sure that the strategy and implementation are type compatible.
strategy:Class<T>: The strategy contract.
name:String: The registration name
implementation:Class<? extends T>: The implementation Class

resolveDefaultableStrategy back to summary

resolveDefaultableStrategy	back to summary
public <T> T resolveDefaultableStrategy(Class<T> strategy, Object strategyReference, T defaultValue) Resolve strategy instances. The incoming reference might be: `null` - in which case defaultValue is returned. An actual instance of the strategy type - it is returned, as is A reference to the implementation `Class` - an instance is created by calling `Class#newInstance()` (aka, the class's no-arg ctor). The name of the implementation class - First the implementation's `Class` reference is resolved, and then an instance is created by calling `Class#newInstance()` Parameters <T> The type of the strategy. Used to make sure that the strategy and implementation are type compatible. strategy:Class<T> The type (interface) of the strategy to be resolved. strategyReference:Object The reference to the strategy for which we need to resolve an instance. defaultValue:T THe default value to use if strategyReference is null Returns:T The strategy instance

public <T> T resolveDefaultableStrategy(Class<T> strategy, Object strategyReference, T defaultValue)

Resolve strategy instances. The incoming reference might be:

null - in which case defaultValue is returned.
An actual instance of the strategy type - it is returned, as is
A reference to the implementation Class - an instance is created by calling Class#newInstance() (aka, the class's no-arg ctor).
The name of the implementation class - First the implementation's Class reference is resolved, and then an instance is created by calling Class#newInstance()

Parameters

<T>: The type of the strategy. Used to make sure that the strategy and implementation are type compatible.
strategy:Class<T>: The type (interface) of the strategy to be resolved.
strategyReference:Object: The reference to the strategy for which we need to resolve an instance.
defaultValue:T: THe default value to use if strategyReference is null

Returns:T

The strategy instance

resolveDefaultableStrategy back to summary

resolveDefaultableStrategy	back to summary
public <T> T resolveDefaultableStrategy(Class<T> strategy, Object strategyReference, Callable<T> defaultResolver) Resolve strategy instances. The incoming reference might be: `null` - in which case defaultValue is returned. An actual instance of the strategy type - it is returned, as is A reference to the implementation `Class` - an instance is created by calling `Class#newInstance()` (aka, the class's no-arg ctor). The name of the implementation class - First the implementation's `Class` reference is resolved, and then an instance is created by calling `Class#newInstance()` Parameters <T> The type of the strategy. Used to make sure that the strategy and implementation are type compatible. strategy:Class<T> The type (interface) of the strategy to be resolved. strategyReference:Object The reference to the strategy for which we need to resolve an instance. defaultResolver:Callable<T> A strategy for resolving the default value strategyReference resolves to null. Returns:T The strategy instance

public <T> T resolveDefaultableStrategy(Class<T> strategy, Object strategyReference, Callable<T> defaultResolver)

Resolve strategy instances. The incoming reference might be:

null - in which case defaultValue is returned.
An actual instance of the strategy type - it is returned, as is
A reference to the implementation Class - an instance is created by calling Class#newInstance() (aka, the class's no-arg ctor).
The name of the implementation class - First the implementation's Class reference is resolved, and then an instance is created by calling Class#newInstance()

Parameters

<T>: The type of the strategy. Used to make sure that the strategy and implementation are type compatible.
strategy:Class<T>: The type (interface) of the strategy to be resolved.
strategyReference:Object: The reference to the strategy for which we need to resolve an instance.
defaultResolver:Callable<T>: A strategy for resolving the default value strategyReference resolves to null.

Returns:T

The strategy instance

resolveStrategy back to summary

resolveStrategy	back to summary
public <T> T resolveStrategy(Class<T> strategy, @Nullable Object strategyReference) Resolve strategy instances. See discussion on `resolveDefaultableStrategy`. Only difference is that here, the implied default value is `null`. Parameters <T> The type of the strategy. Used to make sure that the strategy and implementation are type compatible. strategy:Class<T> The type (interface) of the strategy to be resolved. strategyReference:@Nullable Object The reference to the strategy for which we need to resolve an instance. Returns:T The strategy instance

public <T> T resolveStrategy(Class<T> strategy, @Nullable Object strategyReference)

Resolve strategy instances. See discussion on resolveDefaultableStrategy. Only difference is that here, the implied default value is null.

Parameters

<T>: The type of the strategy. Used to make sure that the strategy and implementation are type compatible.
strategy:Class<T>: The type (interface) of the strategy to be resolved.
strategyReference:@Nullable Object: The reference to the strategy for which we need to resolve an instance.

Returns:T

The strategy instance

resolveStrategy	back to summary
public <T> T resolveStrategy(Class<T> strategy, Object strategyReference, Callable<T> defaultResolver, StrategyCreator<T> creator)

resolveStrategy	back to summary
public <T> T resolveStrategy(Class<T> strategy, Object strategyReference, T defaultValue, StrategyCreator<T> creator)

selectStrategyImplementor	back to summary
public <T> Class<? extends T> selectStrategyImplementor(Class<T> strategy, String name) Locate the named strategy implementation. Parameters <T> The type of the strategy. Used to make sure that the strategy and implementation are type compatible. strategy:Class<T> The type of strategy to be resolved. name:String The name of the strategy to locate; might be either a registered name or the implementation FQN. Returns:Class<? extends T> The named strategy implementation class.

selectStrategyImplementor

back to summary

public <T> Class<? extends T> selectStrategyImplementor(Class<T> strategy, String name)

Locate the named strategy implementation.

Parameters

<T>: The type of the strategy. Used to make sure that the strategy and implementation are type compatible.
strategy:Class<T>: The type of strategy to be resolved.
name:String: The name of the strategy to locate; might be either a registered name or the implementation FQN.

Returns:Class<? extends T>

The named strategy implementation class.

unRegisterStrategyImplementor	back to summary
public <T> void unRegisterStrategyImplementor(Class<T> strategy, Class<? extends T> implementation) Un-registers a named implementor of a particular strategy contract. Un-registers all named registrations for the given strategy contract naming the given class. Parameters <T> The type of the strategy. Used to make sure that the strategy and implementation are type compatible. strategy:Class<T> The strategy contract. implementation:Class<? extends T> The implementation Class

unRegisterStrategyImplementor

back to summary

public <T> void unRegisterStrategyImplementor(Class<T> strategy, Class<? extends T> implementation)

Un-registers a named implementor of a particular strategy contract. Un-registers all named registrations for the given strategy contract naming the given class.

Parameters

<T>: The type of the strategy. Used to make sure that the strategy and implementation are type compatible.
strategy:Class<T>: The strategy contract.
implementation:Class<? extends T>: The implementation Class

public Interface StrategySelector

Method Summary

Method Detail