net.markenwerk.commons.interfaces

Interface Provider<Product>

Type Parameters:

Product - The type of the values to be provided.

public interface Provider<Product>

A Provider provides values of the corresponding product type.

Implementers may provide a new instance of the product each time provide() is called, but aren't required to do so. An instance of the product that has already been returned once, may be returned again for any or all following calls.

A Provider is intended to be used in a situation, where a mechanism to retrieve a value is more desirable than having the value from the start. These are usually, but not necessarily, situations where the following two conditions are met.

• It is not certain that the value will be used.
• It is likely that it is a costly operation to create the value.

The second condition may only be true for the first call to provide() since the Provider is allowed to cache and reuse the value.

Since:

1.0.0

Author:

Torsten Krause (tk at markenwerk dot net)

Method Summary

Modifier and Type	Method and Description
Product	provide() Provides a product, This may be a costly operation.

Method Detail

provide

Product provide()
         throws ProvisioningException

Provides a product, This may be a costly operation.

Implementers should catch any exception and wrap them in a ProvisioningException.

Implementers may provide a new instance of the product each time this method is called, but aren't required to do so. An instance of the product that has already been returned once, may be returned again in any or all following calls.

Returns:

The provided product.

Throws:

ProvisioningException - If the provisioning of the product failed.