org.glassfish.jersey.server.internal.routing.Router Maven / Gradle / Ivy
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package org.glassfish.jersey.server.internal.routing;
import java.util.Collections;
import org.glassfish.jersey.server.ContainerRequest;
import com.google.common.collect.Lists;
/**
* Hierarchical request router that can be used to create dynamic routing tree
* structures. Each routing tree can be executed using a dedicated
* {@link RoutingStage routing stage}.
*
* @author Marek Potociar (marek.potociar at oracle.com)
*/
public interface Router {
/**
* Hierarchical request routing continuation.
*
* A continuation of a hierarchical request routing is represented
* by an ordered collection of next level of routers resulting
* in a hierarchical depth-first (depth-only) request routing.
*
*/
public static final class Continuation {
private final ContainerRequest request;
private final Iterable next;
/**
* Create a terminal continuation from the routed request.
*
* @param result routed request.
* @return terminal continuation with no {@link #next() next level routers}
* in the routing hierarchy and the supplied routed request.
*/
public static Continuation of(final ContainerRequest result) {
return new Continuation(result, null);
}
/**
* Create a continuation from the routed request and a collection
* of next level routers.
*
* @param result routed request.
* @param next next level routers.
* @return a continuation with the supplied next level routers to be invoked
* {@link #next() next} in the routing chain and the supplied routed
* request.
*/
public static Continuation of(final ContainerRequest result, Iterable next) {
return new Continuation(result, next);
}
/**
* Create a continuation from the routed request and a single
* of next level routers.
*
* @param request routed request.
* @param next next level router.
* @return a continuation with the supplied next level router to be invoked
* {@link #next() next} in the routing chain and the supplied routed
* request.
*/
public static Continuation of(final ContainerRequest request, final Router next) {
return new Continuation(request, Lists.newArrayList(next));
}
private Continuation(final ContainerRequest request, final Iterable next) {
this.request = request;
this.next = (next == null) ? Collections.emptyList() : next;
}
/**
* Get the routed request context.
*
* @return routed request context.
*/
public ContainerRequest requestContext() {
return request;
}
/**
* Get the next level routers to be invoked or {@code an empty} if no next
* level routers are {@link #hasNext() present}.
*
* @return the next level routers to be invoked or an empty collection if not
* present.
*/
public Iterable next() {
return next;
}
/**
* Check if there are any next level routers present in the continuation.
*
* The absence of any next level routers in the continuation indicates that the
* request routing reached a leaf stage.
*
*
* @return {@code true} if there are any next level routers present in the continuation,
* {@code false} otherwise.
*/
public boolean hasNext() {
return next.iterator().hasNext();
}
}
/**
* A {@link Router} builder.
*/
public static interface Builder {
/**
* Add new child node into the {@link Router hierarchical request router}
* being built.
*
* @param child new child node to be added.
* @return updated builder instance.
*/
public Builder child(Router child);
/**
* Build a {@link Router hierarchical router} for the transformation of
* a given data type.
*
* @return hierarchical stage.
*/
public Router build();
}
/**
* Performs a request routing task and returns the routed request together with
* a {@link Continuation routing continuation}.
*
* @param data data to be transformed.
* @return a processing continuation.
*/
public Continuation apply(ContainerRequest data);
}