org.ow2.cmi.lb.policy
Interface IPolicy<T extends LoadBalanceable>

Type Parameters:

T - The type of object that was load-balanced

public interface IPolicy<T extends LoadBalanceable>

Interface of the policies for load-balancing.

Author:

The new CMI team

Method Summary

T	choose(java.util.Collection<T> loadBalanceables) Chooses a load-balanceable among the list of load-balanceables.
IStrategy<T>	getStrategy() Return a strategy to modify the behavior of this policy.
<ReturnType> DecisionManager<ReturnType>	onChoose(java.lang.reflect.Method method, java.lang.Object[] parameters, ReturnType chosenValue) Return a decision when a server is chosen and its delegate retrieved.
DecisionManager<java.lang.Void>	onInvokeException(java.lang.reflect.Method method, java.lang.Object[] parameters, T loadBalanceable, java.lang.Throwable thr) Returns a decision when an exception is thrown during an invocation for a given load-balanceable.
DecisionManager<java.lang.Void>	onLookupException(T loadBalanceable, java.lang.Throwable thr) Returns a decision when an exception is thrown during an access to a registry for a given load-balanceable.
<ReturnType> DecisionManager<ReturnType>	onReturn(java.lang.reflect.Method method, java.lang.Object[] parameters, T loadBalanceable, ReturnType retVal) Returns a decision when the invocation of a remote method ends.
void	setStrategy(IStrategy<T> strategy) Sets a strategy to modify the behavior of this policy.

Method Detail

choose

T choose(java.util.Collection<T> loadBalanceables)
                                 throws NoLoadBalanceableException

Chooses a load-balanceable among the list of load-balanceables.

Parameters:

loadBalanceables - a list of load-balanceables

Returns:

the chosen load-balanceable

Throws:

NoLoadBalanceableException - if no server is available

getStrategy

IStrategy<T> getStrategy()

Return a strategy to modify the behavior of this policy.

Returns:

a strategy to modify the behavior of this policy

setStrategy

void setStrategy(IStrategy<T> strategy)

Sets a strategy to modify the behavior of this policy.

Parameters:

strategy - a strategy of load-balancing

onLookupException

DecisionManager<java.lang.Void> onLookupException(T loadBalanceable,
                                                  java.lang.Throwable thr)

Returns a decision when an exception is thrown during an access to a registry for a given load-balanceable.

Parameters:

loadBalanceable - the load-balanceable that have caused the exception

thr - the exception that is thrown

Returns:

the decision when an exception is thrown during an access to a registry for a given load-balanceable

onInvokeException

DecisionManager<java.lang.Void> onInvokeException(java.lang.reflect.Method method,
                                                  java.lang.Object[] parameters,
                                                  T loadBalanceable,
                                                  java.lang.Throwable thr)

Returns a decision when an exception is thrown during an invocation for a given load-balanceable.

Parameters:

method - the method that was invoked

parameters - the parameters of the method

loadBalanceable - the load-balanceable that have caused the exception

thr - the exception that is thrown

Returns:

the decision when an exception is thrown during an invocation for a given load-balanceable

onChoose

<ReturnType> DecisionManager<ReturnType> onChoose(java.lang.reflect.Method method,
                                                  java.lang.Object[] parameters,
                                                  ReturnType chosenValue)

Return a decision when a server is chosen and its delegate retrieved.

Type Parameters:

ReturnType - the type of delegate

Parameters:

method - the method that was invoked

parameters - the parameters of the method

chosenValue - the delegate of chosen server

Returns:

the decision when the server is chosen and its delegate retrieved

onReturn

<ReturnType> DecisionManager<ReturnType> onReturn(java.lang.reflect.Method method,
                                                  java.lang.Object[] parameters,
                                                  T loadBalanceable,
                                                  ReturnType retVal)

Returns a decision when the invocation of a remote method ends.

Type Parameters:

ReturnType - the type of the returned value

Parameters:

method - the method that was invoked

parameters - the parameters of the method

loadBalanceable - the load-balanceable used for the invocation

retVal - the returned value

Returns:

the decision when the invocation of a remote method ends