jersey 官方例子

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However, if you add GPL Version 2 code and therefore, elected the GPL Version 2 license, then the option applies only if the new code is made subject to such option by the copyright holder. --> Reactive Clients Jersey Reactive Client Extensions Example ========================================================== This example demonstrates how data from multiple resources and in various formats (json, xml) can be combined into a form suitable to ones requirements. The example show and compares usage of standard JAX-RS sync client, JAX-RS async client, Jersey's Observable (RxJava) client extension and Jersey's ListenableFuture (Guava) client extension. The application consists of two parts: - **"Remote"**, that can be considered to be deployed on a remote machine. In fact each resource from `org.glassfish.jersey.examples.rx.remote` package can be deployed on a separate remote machine as every resource represents a service of it's own. - **Note:** `DestinationResource` returns response entities as `JSON` while `CalculationResource` and `ForecastResource` as `XML`. - **"Agent"**, which is a synchronization/orchestration layer. This layer, also deployed as a server application, fetches data from all needed resources (using JAX-RS Client API) and combine them together. The combined result is then sent to the client that invoked the original request on the orchestration layer. Every "agent" resource (package `org.glassfish.jersey.examples.rx.agent`) invokes the following requests to the "remote" resource: - Obtain **visited** destinations for a user. (User identification is propagated via request header and basically everything about a user maximally simplified since it's out of scope of this example) - Obtain **recommended** destinations for a user. Requests obtaining **visited** and **recommended** destinations are independent and can be run in parallel. - Obtain weather **forecasts** for recommended destinations. New client request is invoked for every recommended destination. Obtaining weather **forecasts** depend on actual **recommended** destinations. - Obtain trip **calculations** (prices) for recommended destinations. New client request is invoked for every recommended destination. Obtaining trip **calculations** depend on actual **recommended** destinations. **forecast** and **calculation** requests are independent on each other and can be invoked in parallel. Contents -------- The mapping of the URI path space is presented in the following table: URI path | Resource class | HTTP methods | Allowed values -------------------------------------------------- | ------------------------------- | -------------- | ------------------------------------------------------------------------------ **_/rx/agent/sync_** | SyncAgentResource | GET | returns JSON **_/rx/agent/async_** | AsyncAgentResource | GET | returns JSON **_/rx/agent/observable_** | ObservableAgentResource | GET | returns JSON **_/rx/agent/listenable_** | ListenableFutureAgentResource | GET | returns JSON **_/rx/remote/destination/visited_** | DestinationResource | GET | returns JSON **_/rx/remote/destination/recommended_** | DestinationResource | GET | returns JSON **_/rx/remote/forecast/{destination}_** | ForecastResource | GET | destination - name of a country; returns XML (random value) **_/rx/remote/calculation/from/{from}/to/{to}_** | CalculationResource | GET | from - name of a country, to - name of a country; returns XML (random value) Application is Servlet 3 based, web.xml-less. Everything needed (resources/providers) is registered in `RxApplication`. Sample Response --------------- Agent responses look similar to the following one: ```javascript { "visited" : [ { "destination" : "Antigua & Barbuda" }, { "destination" : "Guinea" }, { "destination" : "Malta" }, { "destination" : "Denmark" }, { "destination" : "Tajikistan" } ], "recommended" : [ { "destination" : "Bolivia", "forecast" : "Showers", "price" : 1359 }, { "destination" : "Yemen", "forecast" : "Haze", "price" : 8032 }, { "destination" : "Dominican Republic", "forecast" : "Cloudy", "price" : 1141 }, { "destination" : "Korea South", "forecast" : "Mostly Sunny", "price" : 9853 }, { "destination" : "Saudi Arabia", "forecast" : "Fog", "price" : 9063 } ], "processingTime" : 877 } ``` As can be seen the response entity contains 3 main elements: **visited** (list of visited destinations), **recommended** (list of recommended destinations + weather forecast and price calculation) and **processingTime** (describing how long it took to obtain previous two elements). Running the Example ------------------- Run the example as follows: > mvn clean package jetty:run This deploys current example using Jetty. You can access the application at: - <http://localhost:8080/rx/agent/sync> - <http://localhost:8080/rx/agent/async> - <http://localhost:8080/rx/agent/listenable> - <http://localhost:8080/rx/agent/observable> Resources --------- This examples is using the following (3-rd party) libraries: **RxJava** by Netflix - [GitHub](https://github.com/ReactiveX/RxJava) - [GitHub.Wiki](https://github.com/ReactiveX/RxJava/wiki) - [JavaDoc](http://reactivex.io/RxJava/javadoc/) **Guava** by Google - [Homepage](https://code.google.com/p/guava-libraries/) - [ListenableFuture Explained](https://code.google.com/p/guava-libraries/wiki/ListenableFutureExplained) - [JavaDoc](http://docs.guava-libraries.googlecode.com/git/javadoc/ind