io.netty.handler.codec.http.router

Class Router<T>

java.lang.Object

io.netty.handler.codec.http.router.Router<T>

public class Router<T>
extends java.lang.Object

Router that contains information about both route matching orders and HTTP request methods. Routes are devided into 3 sections: "first", "last", and "other". Routes in "first" are matched first, then in "other", then in "last".

Create router

Route targets can be any type. In the below example, targets are classes:

 
 Router<Class> router = new Router<Class>()
   .GET      ("/articles",     IndexHandler.class)
   .GET      ("/articles/:id", ShowHandler.class)
   .POST     ("/articles",     CreateHandler.class)
   .GET      ("/download/:*",  DownloadHandler.class)  // ":*" must be the last token
   .GET_FIRST("/articles/new", NewHandler.class);      // This will be matched first
 
 

Slashes at both ends are ignored. These are the same:

 
 router.GET("articles",   IndexHandler.class);
 router.GET("/articles",  IndexHandler.class);
 router.GET("/articles/", IndexHandler.class);
 
 

You can remove routes by target or by path:

 
 router.removeTarget(IndexHandler.class);
 router.removePath("/articles");
 
 

Match with request method and URI

Use route(HttpMethod, String). From the RouteResult you can extract params embedded in the path and from the query part of the request URI.

404 Not Found target

Use notFound(Object). It will be used as the target when there's no match.

 router.notFound(My404Handler.class);
 

Create reverse route

Use path(HttpMethod, Object, Object...) or path(Object, Object...):

 
 router.path(HttpMethod.GET, IndexHandler.class);
 // Returns "/articles"
 
 

You can skip HTTP method if there's no confusion:

 
 router.path(CreateHandler.class);
 // Also returns "/articles"
 
 

You can specify params as map:

 
 // Things in params will be converted to String
 Map<Object, Object> params = new HashMap<Object, Object>();
 params.put("id", 123);
 router.path(ShowHandler.class, params);
 // Returns "/articles/123"
 
 

Convenient way to specify params:

 
 router.path(ShowHandler.class, "id", 123);
 // Returns "/articles/123"
 
 

Allowed methods

If you want to implement OPTIONS or CORS, you can use allowedMethods(String). For OPTIONS *, use allAllowedMethods().

Constructor Summary

Constructors

Constructor and Description
Router()

Method Summary

Modifier and Type	Method and Description
Router	addRoute(io.netty.handler.codec.http.HttpMethod method, java.lang.String path, T target) Add route to the "other" section.
Router	addRouteFirst(io.netty.handler.codec.http.HttpMethod method, java.lang.String path, T target) Add route to the "first" section.
Router	addRouteLast(io.netty.handler.codec.http.HttpMethod method, java.lang.String path, T target) Add route to the "last" section.
java.util.Set<io.netty.handler.codec.http.HttpMethod>	allAllowedMethods() Returns all methods that this router handles.
java.util.Set<io.netty.handler.codec.http.HttpMethod>	allowedMethods(java.lang.String uri) Returns allowed methods for a specific URI.
Router	ANY_FIRST(java.lang.String path, T target)
Router	ANY_LAST(java.lang.String path, T target)
Router	ANY(java.lang.String path, T target)
Router	CONNECT_FIRST(java.lang.String path, T target)
Router	CONNECT_LAST(java.lang.String path, T target)
Router	CONNECT(java.lang.String path, T target)
Router	DELETE_FIRST(java.lang.String path, T target)
Router	DELETE_LAST(java.lang.String path, T target)
Router	DELETE(java.lang.String path, T target)
Router	GET_FIRST(java.lang.String path, T target)
Router	GET_LAST(java.lang.String path, T target)
Router	GET(java.lang.String path, T target)
Router	HEAD_FIRST(java.lang.String path, T target)
Router	HEAD_LAST(java.lang.String path, T target)
Router	HEAD(java.lang.String path, T target)
T	notFound() Returns the fallback target for use when there's no match at route(HttpMethod, String).
Router	notFound(T target) Sets the fallback target for use when there's no match at route(HttpMethod, String).
Router	OPTIONS_FIRST(java.lang.String path, T target)
Router	OPTIONS_LAST(java.lang.String path, T target)
Router	OPTIONS(java.lang.String path, T target)
Router	PATCH_FIRST(java.lang.String path, T target)
Router	PATCH_LAST(java.lang.String path, T target)
Router	PATCH(java.lang.String path, T target)
java.lang.String	path(io.netty.handler.codec.http.HttpMethod method, T target, java.lang.Object... params) Given a target and params, this method tries to do the reverse routing and returns the path.
java.lang.String	path(T target, java.lang.Object... params) Given a target and params, this method tries to do the reverse routing and returns the path.
Router	POST_FIRST(java.lang.String path, T target)
Router	POST_LAST(java.lang.String path, T target)
Router	POST(java.lang.String path, T target)
Router	PUT_FIRST(java.lang.String path, T target)
Router	PUT_LAST(java.lang.String path, T target)
Router	PUT(java.lang.String path, T target)
void	removePath(java.lang.String path) Removes the route specified by the path.
void	removeTarget(T target) Removes all routes leading to the target.
RouteResult<T>	route(io.netty.handler.codec.http.HttpMethod method, java.lang.String uri) If there's no match, returns the result with notFound as the target if it is set, otherwise returns null.
int	size() Returns the number of routes in this router.
java.lang.String	toString() Returns visualized routing rules.
Router	TRACE_FIRST(java.lang.String path, T target)
Router	TRACE_LAST(java.lang.String path, T target)
Router	TRACE(java.lang.String path, T target)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Router

public Router()

Method Detail

notFound

public T notFound()

Returns the fallback target for use when there's no match at route(HttpMethod, String).

size

public int size()

Returns the number of routes in this router.

addRouteFirst

public Router addRouteFirst(io.netty.handler.codec.http.HttpMethod method,
                            java.lang.String path,
                            T target)

Add route to the "first" section. A path can only point to one target. This method does nothing if the path has already been added.

addRoute

public Router addRoute(io.netty.handler.codec.http.HttpMethod method,
                       java.lang.String path,
                       T target)

Add route to the "other" section. A path can only point to one target. This method does nothing if the path has already been added.

addRouteLast

public Router addRouteLast(io.netty.handler.codec.http.HttpMethod method,
                           java.lang.String path,
                           T target)

Add route to the "last" section. A path can only point to one target. This method does nothing if the path has already been added.

notFound

public Router notFound(T target)

Sets the fallback target for use when there's no match at route(HttpMethod, String).

removePath

public void removePath(java.lang.String path)

Removes the route specified by the path.

removeTarget

public void removeTarget(T target)

Removes all routes leading to the target.

route

public RouteResult<T> route(io.netty.handler.codec.http.HttpMethod method,
                            java.lang.String uri)

If there's no match, returns the result with notFound as the target if it is set, otherwise returns null.

allowedMethods

public java.util.Set<io.netty.handler.codec.http.HttpMethod> allowedMethods(java.lang.String uri)

Returns allowed methods for a specific URI. For OPTIONS *, use allAllowedMethods() instead of this method.

allAllowedMethods

public java.util.Set<io.netty.handler.codec.http.HttpMethod> allAllowedMethods()

Returns all methods that this router handles. For OPTIONS *.

path

public java.lang.String path(io.netty.handler.codec.http.HttpMethod method,
                             T target,
                             java.lang.Object... params)

Given a target and params, this method tries to do the reverse routing and returns the path. The params are put to placeholders in the path. The params can be a map of placeholder name -> value or ordered values. If a param doesn't have a placeholder, it will be put to the query part of the path.

Returns:

null if there's no match

path

public java.lang.String path(T target,
                             java.lang.Object... params)

Given a target and params, this method tries to do the reverse routing and returns the path. The params are put to placeholders in the path. The params can be a map of placeholder name -> value or ordered values. If a param doesn't have a placeholder, it will be put to the query part of the path.

Returns:

null if there's no match

toString

public java.lang.String toString()

Returns visualized routing rules.

Overrides:

toString in class java.lang.Object

CONNECT

public Router CONNECT(java.lang.String path,
                      T target)

DELETE

public Router DELETE(java.lang.String path,
                     T target)

GET

public Router GET(java.lang.String path,
                  T target)

HEAD

public Router HEAD(java.lang.String path,
                   T target)

OPTIONS

public Router OPTIONS(java.lang.String path,
                      T target)

PATCH

public Router PATCH(java.lang.String path,
                    T target)

POST

public Router POST(java.lang.String path,
                   T target)

PUT

public Router PUT(java.lang.String path,
                  T target)

TRACE

public Router TRACE(java.lang.String path,
                    T target)

ANY

public Router ANY(java.lang.String path,
                  T target)

CONNECT_FIRST

public Router CONNECT_FIRST(java.lang.String path,
                            T target)

DELETE_FIRST

public Router DELETE_FIRST(java.lang.String path,
                           T target)

GET_FIRST

public Router GET_FIRST(java.lang.String path,
                        T target)

HEAD_FIRST

public Router HEAD_FIRST(java.lang.String path,
                         T target)

OPTIONS_FIRST

public Router OPTIONS_FIRST(java.lang.String path,
                            T target)

PATCH_FIRST

public Router PATCH_FIRST(java.lang.String path,
                          T target)

POST_FIRST

public Router POST_FIRST(java.lang.String path,
                         T target)

PUT_FIRST

public Router PUT_FIRST(java.lang.String path,
                        T target)

TRACE_FIRST

public Router TRACE_FIRST(java.lang.String path,
                          T target)

ANY_FIRST

public Router ANY_FIRST(java.lang.String path,
                        T target)

CONNECT_LAST

public Router CONNECT_LAST(java.lang.String path,
                           T target)

DELETE_LAST

public Router DELETE_LAST(java.lang.String path,
                          T target)

GET_LAST

public Router GET_LAST(java.lang.String path,
                       T target)

HEAD_LAST

public Router HEAD_LAST(java.lang.String path,
                        T target)

OPTIONS_LAST

public Router OPTIONS_LAST(java.lang.String path,
                           T target)

PATCH_LAST

public Router PATCH_LAST(java.lang.String path,
                         T target)

POST_LAST

public Router POST_LAST(java.lang.String path,
                        T target)

PUT_LAST

public Router PUT_LAST(java.lang.String path,
                       T target)

TRACE_LAST

public Router TRACE_LAST(java.lang.String path,
                         T target)

ANY_LAST

public Router ANY_LAST(java.lang.String path,
                       T target)