ratpack.impose.UserRegistryImposition Maven / Gradle / Ivy
/*
* Copyright 2015 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ratpack.impose;
import ratpack.func.Function;
import ratpack.registry.Registry;
import ratpack.server.RatpackServerSpec;
/**
* Imposes an extra registry to be joined with the user registry when starting an application.
*
* If present, the imposed registry will be joined with the user registry specified by {@link RatpackServerSpec#registry(Function)}.
* This effectively allows adding extra things to the registry.
*
* @see Impositions
* @since 1.2
*/
public final class UserRegistryImposition implements Imposition {
private final Function registryFunc;
private UserRegistryImposition(Function registryFunc) {
this.registryFunc = registryFunc;
}
/**
* Creates an imposition of an empty registry.
*
* This is equivalent to their being no imposition at all.
*
* @return a empty user registry imposition
*/
public static UserRegistryImposition none() {
return of(Registry.empty());
}
/**
* Creates an imposition of the given registry.
*
* @param registry the registry to join with the user registry
* @return an imposition of the given registry
*/
public static UserRegistryImposition of(Registry registry) {
return of(Function.constant(registry));
}
/**
* Creates an imposition of registry returned by the given function.
*
* The given function receives the user registry as input.
* The function should not return a registry that has been joined with the input.
* The user registry is given as input to allow retrieval from the registry.
*
* @param registry a function that receives the user registry and returns a registry of additions to it
* @return an imposition of the given registry
*/
public static UserRegistryImposition of(Function registry) {
return new UserRegistryImposition(registry);
}
/**
* Returns the registry of additions, taking the original user registry as the argument
*
* @param userRegistry the user registry
* @return a registry to join on to the user registry
* @throws Exception any
*/
public Registry build(Registry userRegistry) throws Exception {
return registryFunc.apply(userRegistry);
}
}