How To Use Rest Services In Java
RESTful web services with Coffee (Jersey / JAX-RS). This tutorial explains how to develop RESTful web services in Coffee. It uses the JAX-RS reference implementation Jersey. In this tutorial Eclipse four.7 (Oxygen), Coffee ane.8, Tomcat half-dozen.0 and JAX-RS 2.0 (with Bailiwick of jersey 2.11) is used.
ane. Residuum - Representational State Transfer
1.i. What is Balance?
Rest is an architectural way which is based on web-standards and the HTTP protocol. This style was initially described by Roy Fielding in 2000. In a REST based architecture everything is a resource. A resource is accessed via a common interface based on the HTTP standard methods. In a Balance based architecture you have a REST server which provides access to the resources. A REST client can access and modify the Residual resource.
Every resource should back up the HTTP mutual operations. Resources are identified by global IDs (which are typically URIs).
Residual allows that resources have different representations, e.g., text, XML, JSON etc. The Rest client tin enquire for a specific representation via the HTTP protocol (content negotiation).
1.2. HTTP methods
The PUT, GET, POST and DELETE methods are typical used in REST based architectures. The following tabular array gives an explanation of these operations.
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Become defines a reading admission of the resource without side-effects. The resource is never inverse via a Go asking, e.g., the request has no side effects (idempotent).
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PUT creates a new resource. It must also be idempotent.
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DELETE removes the resources. The operations are idempotent. They can go repeated without leading to unlike results.
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Mail service updates an existing resource or creates a new resources.
1.iii. RESTFul web services
A RESTFul web services are based on HTTP methods and the concept of REST. A RESTFul spider web service defines the base URI for the services, the supported MIME-types (XML, text, JSON, user-divers, …). It also defines the set of operations (POST, GET, PUT, DELETE) which are supported.
2. Installation of Bailiwick of jersey
ii.one. Use Gradle
compile 'org.glassfish.bailiwick of jersey.containers:bailiwick of jersey-container-servlet:two.25.1' 2.2. Manual setup of Jersey libraries in an Eclipse project
The zip contains the Jersey implementation JAR and its core dependencies. Information technology does not provide dependencies for third party JARs beyond those for JSON support and JavaDoc.
Copy all JARs from your Jersey download into the WEB-INF/lib binder.
three. Web container
For this tutorial you can use whatever web container, for instance Tomcat or the Google App Engine.
If you desire to use Tomcat as servlet container please see Eclipse WTP and Apache Tomcat for instructions on how to install and utilize Eclipse WTP and Apache Tomcat.
The following description is based on a local Apache Tomcat installation.
4. Required setup for Gradle and Eclipse spider web projects
This section describes how to setup Eclipse WTP in a Gradle project. This is required for the following tutorials.
iv.1. Prerequisites
If you have non all the same created a Gradle project, you tin can follow the Buildship tutorial to create i.
4.2. Gradle setup
Open up the build.gradle file and add the following two lines.
apply plugin: 'war' utilise plugin: 'eclipse-wtp' Since we want to create a web application, we want a state of war file (and not a jar file which would exist created by Gradle with the Java plugin). The eclipse-wtp plugin helps you to generate the Eclipse WTP project files.
At present, add a new folder with the name WebContent to your projects root. To do and so, . Add some other folder with the name WEB-INF to your WebContent binder.
The next footstep is to add together a xml file with the name web.xml to the created Spider web-INF folder. To practice so menu: right click on the created folder name[New > Other…] and select XML file.
Your folder structure should at present look something like this:
Now the newly created folders with the web.xml in it has to exist added to the build.gradle file by adding the post-obit line:
project.webAppDirName = 'WebContent' Perform a right-click on the project and select . This will add diverse new tasks to your Gradle Tasks view.
Run the eclipseWTP task to generate the Eclipse WTP project files and terminate the projection setup.
five. Prerequisites
The following clarification assumes that you are familiar with creating spider web applications in Eclipse. See Eclipse WTP evolution for an introduction into creating web applications with Eclipse.
6. Create your showtime RESTful Webservice
6.ane. Create a new Gradle project and configure bailiwick of jersey usage and Eclipse WTP
Create a new Gradle project named com.vogella.jersey.get-go with com.vogella.jersey.first as the top-level package proper noun and configure Eclipse WTP. You can follow Required setup for Gradle and Eclipse web projects to become started.
To import the Jersey dependencies, add the post-obit dependency to your build.gradle file.
compile 'org.glassfish.jersey.containers:jersey-container-servlet:2.25.1' 6.2. Coffee Class
Create the following class.
packet com.vogella.jersey.start ; import javax.ws.rs.Go ; import javax.ws.rs.Path ; import javax.ws.rs.Produces ; import javax.ws.rs.core.MediaType ; // Plainly old Java Object it does not extend every bit class or implements // an interface // The course registers its methods for the HTTP Become request using the @GET annotation. // Using the @Produces annotation, information technology defines that it can deliver several MIME types, // text, XML and HTML. // The browser requests per default the HTML MIME type. //Sets the path to base URL + /hullo @Path ( "/hi" ) public grade Hello { // This method is called if TEXT_PLAIN is asking @Go @Produces ( MediaType . TEXT_PLAIN ) public String sayPlainTextHello () { return "Hullo Jersey" ; } // This method is called if XML is request @Become @Produces ( MediaType . TEXT_XML ) public String sayXMLHello () { return "<?xml version=\"ane.0\"?>" + "<hello> Hello Bailiwick of jersey" + "</hi>" ; } // This method is called if HTML is asking @Go @Produces ( MediaType . TEXT_HTML ) public String sayHtmlHello () { return "<html> " + "<title>" + "How-do-you-do Jersey" + "</title>" + "<body><h1>" + "Howdy Jersey" + "</body></h1>" + "</html> " ; } } This class annals itself as a go resource via the @GET note. Via the @Produces annotation information technology defines that it delivers the text and the HTML MIME types. It also defines via the @Path annotation that its service is bachelor nether the hi URL.
The browser volition always request the HTML MIME type. To see the text version, you tin use tool like curl.
6.3. Define Jersey Servlet dispatcher
You need to register Bailiwick of jersey every bit the servlet dispatcher for Residuum requests.
Open the file web.xml and change it to the following.
<?xml version="i.0" encoding="UTF-eight"?> <web-app xmlns:xsi= "http://www.w3.org/2001/XMLSchema-example" xmlns= "http://java.sun.com/xml/ns/javaee" xsi:schemaLocation= "http://java.dominicus.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id= "WebApp_ID" version= "3.0" > <display-name>com.vogella.jersey.first</brandish-proper name> <servlet> <servlet-name>Jersey Remainder Service</servlet-proper name> <servlet-grade>org.glassfish.bailiwick of jersey.servlet.ServletContainer</servlet-class> <!-- Register resources and providers under com.vogella.bailiwick of jersey.offset parcel. --> <init-param> <param-name>jersey.config.server.provider.packages</param-name> <param-value>com.vogella.jersey.first</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-proper name>Bailiwick of jersey Residuum Service</servlet-name> <url-blueprint>/residue/*</url-pattern> </servlet-mapping> </web-app> The parameter jersey.config.server.provider.packages defines in which package Jersey will wait for the web service classes. This property must indicate to your resources classes. The URL blueprint defines the part of the base URL your application will be placed.
6.4. Run your rest service
To run your web awarding in Eclipse, brand sure to run the gradle task eclipseWtp first. Afterwards, you should be able to run the application by
You should be able to access your resources nether the following URL:
http://localhost:8080/com.vogella.bailiwick of jersey.first/rest/hello
This URL is derived from the context root value in the projects properties Web Project Settings (by default, this is your application name), augmented with the servlet-mapping URL-pattern and the hullo @Path annotation from your form file. You should become the message "Hi Jersey".
As nosotros are using Gradle, if yous want to update the context root include the following in your build.gradle and update your spider web container ( in the Servers Eclipse View).
eclipse { wtp { component { contextPath = ' newName ' } } } The browser requests the HTML representation of your resource. In the next chapter we are going to write a client which will read the XML representation.
vii. Create a REST customer
Bailiwick of jersey contains a REST client library which tin can be used for testing or to build a real client in Java. The usage of this library is demonstrated in the following tutorial.
Create a new Coffee gradle project with com.vogella.jersey.showtime.client every bit top-level package proper name and add together following dependency to your build.gradle file to import the Jersey dependencies.
compile 'org.glassfish.jersey.containers:jersey-container-servlet:ii.25.1' Create the following test class.
package com.vogella.bailiwick of jersey.first.client ; import java.internet.URI ; import javax.ws.rs.customer.Client ; import javax.ws.rs.client.ClientBuilder ; import javax.ws.rs.client.WebTarget ; import javax.ws.rs.core.MediaType ; import javax.ws.rs.core.Response ; import javax.ws.rs.core.UriBuilder ; import org.glassfish.jersey.customer.ClientConfig ; public course Test { public static void main ( String [] args ) { ClientConfig config = new ClientConfig (); Client client = ClientBuilder . newClient ( config ); WebTarget target = customer . target ( getBaseURI ()); Cord response = target . path ( "remainder" ). path ( "howdy" ). asking (). accept ( MediaType . TEXT_PLAIN ). get ( Response . class ) . toString (); String plainAnswer = target . path ( "rest" ). path ( "hullo" ). request (). accept ( MediaType . TEXT_PLAIN ). get ( String . course ); Cord xmlAnswer = target . path ( "rest" ). path ( "howdy" ). request (). have ( MediaType . TEXT_XML ). get ( String . form ); String htmlAnswer = target . path ( "rest" ). path ( "hello" ). request (). take ( MediaType . TEXT_HTML ). get ( Cord . class ); Arrangement . out . println ( response ); System . out . println ( plainAnswer ); System . out . println ( xmlAnswer ); System . out . println ( htmlAnswer ); } private static URI getBaseURI () { return UriBuilder . fromUri ( "http://localhost:8080/com.vogella.jersey.first" ). build (); } } eight. RESTful spider web services and JAXB
JAX-RS supports the automatic creation of XML and JSON via JAXB. For an introduction into XML please meet Java and XML - Tutorial. For an introduction into JAXB please see JAXB. You tin can go along this tutorial without reading these tutorials, merely they contain more background information.
8.ane. Create new Gradle project
Create a new Gradle projection named com.vogella.jersey.jaxb with com.vogella.jersey.jaxb equally the top-level package proper name and configure Eclipse WTP. You can follow Required setup for Gradle and Eclipse spider web projects to become started. To enable JSON support, add together the post-obit dependency to your build.gradle file. The second line automatically adds support for the media type awarding/json.
compile ' org . glassfish . jersey . containers : jersey - container - servlet: 2.25 . one ' compile ' org . glassfish . jersey . media : jersey - media - json - jackson: 2.25 . i ' 8.2. Create Java classes
Create your domain grade.
package com.vogella.jersey.jaxb ; import javax.xml.bind.annotation.XmlRootElement ; @XmlRootElement // JAX-RS supports an automatic mapping from JAXB annotated form to XML and JSON // Isn't that absurd? public class Todo { private Cord summary ; individual String clarification ; public Cord getSummary () { return summary ; } public void setSummary ( String summary ) { this . summary = summary ; } public String getDescription () { return description ; } public void setDescription ( String description ) { this . clarification = description ; } } Create the following resource class. This class but returns an instance of the Todo class.
bundle com.vogella.jersey.jaxb ; import javax.ws.rs.GET ; import javax.ws.rs.Path ; import javax.ws.rs.Produces ; import javax.ws.rs.core.MediaType ; @Path ( "/todo" ) public class TodoResource { // This method is chosen if XML is requested @GET @Produces ({ MediaType . APPLICATION_XML }) public Todo getXML () { Todo todo = new Todo (); todo . setSummary ( "Application XML Todo Summary" ); todo . setDescription ( "Application XML Todo Description" ); render todo ; } // This method is chosen if JSON is requested @GET @Produces ({ MediaType . APPLICATION_JSON }) public Todo getJSON () { Todo todo = new Todo (); todo . setSummary ( "Application JSON Todo Summary" ); todo . setDescription ( "Awarding JSON Todo Description" ); return todo ; } // This tin can be used to test the integration with the browser @Become @Produces ({ MediaType . TEXT_XML }) public Todo getHTML () { Todo todo = new Todo (); todo . setSummary ( "XML Todo Summary" ); todo . setDescription ( "XML Todo Description" ); return todo ; } } Alter spider web.xml to the following.
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi= "http://world wide web.w3.org/2001/XMLSchema-instance" xmlns= "http://coffee.sun.com/xml/ns/javaee" xsi:schemaLocation= "http://coffee.lord's day.com/xml/ns/javaee http://java.lord's day.com/xml/ns/javaee/spider web-app_3_0.xsd" id= "WebApp_ID" version= "3.0" > <brandish-name>com.vogella.bailiwick of jersey.jaxb</display-name> <servlet> <servlet-name>Jersey REST Service</servlet-name> <servlet-form>org.glassfish.jersey.servlet.ServletContainer</servlet-class> <!-- Register resources and providers nether com.vogella.jersey.first package. --> <init-param> <param-proper name>jersey.config.server.provider.packages</param-name> <param-value>com.vogella.jersey.jaxb</param-value> </init-param> <load-on-startup>ane</load-on-startup> </servlet> <servlet-mapping> <servlet-proper noun>Bailiwick of jersey REST Service</servlet-name> <url-pattern>/rest/*</url-pattern> </servlet-mapping> </web-app> Run you lot web awarding in Eclipse and validate that you can access your service. Your awarding should be available under the post-obit URL.
http://localhost:8080/com.vogella.bailiwick of jersey.jaxb/residual/todo 8.3. Create a client
Create a new Java Gradle projection with com.vogella.jersey.jaxbclient every bit top-level bundle name and add the following dependencies to your build.gradle file to import the Jersey dependencies and enable JSON back up.
compile 'org.glassfish.jersey.containers:jersey-container-servlet:ii.25.1' compile 'org.glassfish.jersey.media:jersey-media-json-jackson:ii.25.one' Create the post-obit exam course.
package com.vogella.jersey.jaxbclient ; import coffee.net.URI ; import javax.ws.rs.client.Customer ; import javax.ws.rs.customer.ClientBuilder ; import javax.ws.rs.client.WebTarget ; import javax.ws.rs.core.MediaType ; import javax.ws.rs.cadre.UriBuilder ; import org.glassfish.jersey.client.ClientConfig ; import com.fasterxml.jackson.jaxrs.annotation.JacksonFeatures ; public class TodoTest { public static void main ( String [] args ) { ClientConfig config = new ClientConfig (); Customer client = ClientBuilder . newClient ( config ); WebTarget target = customer . target ( getBaseURI ()); // Become XML Cord xmlResponse = target . path ( "rest" ). path ( "todo" ). request () . have ( MediaType . TEXT_XML ). get ( String . grade ); // Become XML for application Cord xmlAppResponse = target . path ( "rest" ). path ( "todo" ). asking () . accept ( MediaType . APPLICATION_XML ). get ( Cord . class ); // Go JSON for application String jsonResponse = target . path ( "rest" ). path ( "todo" ). request () . accept ( MediaType . APPLICATION_JSON ). go ( String . class ); Organisation . out . println ( xmlResponse ); System . out . println ( xmlAppResponse ); System . out . println ( jsonResponse ); } individual static URI getBaseURI () { return UriBuilder . fromUri ( "http://localhost:8080/com.vogella.jersey.jaxb" ). build (); } } 9. CRUD RESTful webservice
This section creates a CRUD (Create, Read, Update, Delete) restful web service. Information technology will allow to maintain a list of TODOs in your spider web application via HTTP calls.
9.i. Project
Create a new Gradle project called com.vogella.jersey.todo with com.vogella.jersey.todo as top-level package name. Add together the post-obit to dependency to your build.gradle file and make likewise sure, that yous enabled Eclipse WTP support past following Required setup for Gradle and Eclipse web projects.
compile 'org.glassfish.bailiwick of jersey.containers:jersey-container-servlet:2.25.1' compile 'javax.servlet:javax.servlet-api:4.0.0-b07' Change the web.xml file to the following.
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi= "http://www.w3.org/2001/XMLSchema-instance" xmlns= "http://java.sun.com/xml/ns/javaee" xsi:schemaLocation= "http://java.dominicus.com/xml/ns/javaee http://java.dominicus.com/xml/ns/javaee/web-app_3_0.xsd" id= "WebApp_ID" version= "3.0" > <display-proper noun>com.vogella.jersey.todo</display-name> <servlet> <servlet-name>Jersey REST Service</servlet-name> <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class> <!-- Register resources and providers nether com.vogella.jersey.first package. --> <init-param> <param-name>jersey.config.server.provider.packages</param-name> <param-value>com.vogella.bailiwick of jersey.todo</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-proper noun>Jersey REST Service</servlet-name> <url-blueprint>/remainder/*</url-design> </servlet-mapping> </spider web-app> Create the post-obit data model and a Singleton which serves equally the data provider for the model. We use the implementation based on an enumeration. Delight run across the link for details. The Todo class is annotated with a JAXB note. Encounter Java and XML to learn near JAXB.
package com.vogella.jersey.todo ; import javax.xml.bind.notation.XmlRootElement ; @XmlRootElement public grade Todo { individual String id ; private String summary ; individual String description ; public Todo (){ } public Todo ( Cord id , String summary ){ this . id = id ; this . summary = summary ; } public Cord getId () { return id ; } public void setId ( Cord id ) { this . id = id ; } public Cord getSummary () { return summary ; } public void setSummary ( String summary ) { this . summary = summary ; } public Cord getDescription () { render description ; } public void setDescription ( String description ) { this . description = description ; } } package com.vogella.jersey.todo ; import java.util.HashMap ; import java.util.Map ; import com.vogella.bailiwick of jersey.todo.Todo ; public enum TodoDao { example ; private Map < String , Todo > contentProvider = new HashMap <>(); private TodoDao () { Todo todo = new Todo ( "1" , "Acquire Remainder" ); todo . setDescription ( "Read https://world wide web.vogella.com/tutorials/REST/article.html" ); contentProvider . put ( "i" , todo ); todo = new Todo ( "2" , "Do something" ); todo . setDescription ( "Read consummate http://world wide web.vogella.com" ); contentProvider . put ( "2" , todo ); } public Map < String , Todo > getModel (){ return contentProvider ; } } 9.2. Create a simple HTML class
The REST service can be used via HTML forms. The post-obit HTML form will allow to post new data to the service. Create the following page called create_todo.html in the WebContent folder.
<!DOCTYPE html> <html> <caput> <title>Grade to create a new resources</championship> </caput> <body> <class action= "../com.vogella.jersey.todo/rest/todos" method= "POST" > <characterization for= "id" >ID</label> <input proper name= "id" /> <br/> <label for= "summary" >Summary</characterization> <input proper noun= "summary" /> <br/> Description: <TEXTAREA NAME= "description" COLS= 40 ROWS= vi ></TEXTAREA> <br/> <input type= "submit" value= "Submit" /> </grade> </body> </html> 9.iii. Rest Service
Create the following classes which will be used as REST resources.
package com.vogella.jersey.todo ; import javax.ws.rs.Consumes ; import javax.ws.rs.DELETE ; import javax.ws.rs.GET ; import javax.ws.rs.PUT ; import javax.ws.rs.Produces ; import javax.ws.rs.cadre.Context ; import javax.ws.rs.cadre.MediaType ; import javax.ws.rs.core.Request ; import javax.ws.rs.core.Response ; import javax.ws.rs.core.UriInfo ; import javax.xml.bind.JAXBElement ; import com.vogella.jersey.todo.TodoDao ; import com.vogella.jersey.todo.Todo ; public class TodoResource { @Context UriInfo uriInfo ; @Context Request request ; String id ; public TodoResource ( UriInfo uriInfo , Request request , String id ) { this . uriInfo = uriInfo ; this . request = request ; this . id = id ; } //Awarding integration @Become @Produces ({ MediaType . APPLICATION_XML , MediaType . APPLICATION_JSON }) public Todo getTodo () { Todo todo = TodoDao . case . getModel (). go ( id ); if ( todo == null ) throw new RuntimeException ( "Get: Todo with " + id + " not found" ); return todo ; } // for the browser @Become @Produces ( MediaType . TEXT_XML ) public Todo getTodoHTML () { Todo todo = TodoDao . instance . getModel (). get ( id ); if ( todo == cypher ) throw new RuntimeException ( "Become: Todo with " + id + " not found" ); render todo ; } @PUT @Consumes ( MediaType . APPLICATION_XML ) public Response putTodo ( JAXBElement < Todo > todo ) { Todo c = todo . getValue (); return putAndGetResponse ( c ); } @DELETE public void deleteTodo () { Todo c = TodoDao . case . getModel (). remove ( id ); if ( c == nix ) throw new RuntimeException ( "Delete: Todo with " + id + " non found" ); } individual Response putAndGetResponse ( Todo todo ) { Response res ; if ( TodoDao . instance . getModel (). containsKey ( todo . getId ())) { res = Response . noContent (). build (); } else { res = Response . created ( uriInfo . getAbsolutePath ()). build (); } TodoDao . case . getModel (). put ( todo . getId (), todo ); return res ; } } bundle com.vogella.jersey.todo ; import java.io.IOException ; import java.util.ArrayList ; import coffee.util.List ; import javax.servlet.http.HttpServletResponse ; import javax.ws.rs.Consumes ; import javax.ws.rs.FormParam ; import javax.ws.rs.GET ; import javax.ws.rs.POST ; import javax.ws.rs.Path ; import javax.ws.rs.PathParam ; import javax.ws.rs.Produces ; import javax.ws.rs.core.Context ; import javax.ws.rs.core.MediaType ; import javax.ws.rs.core.Request ; import javax.ws.rs.core.UriInfo ; import com.vogella.jersey.todo.TodoDao ; import com.vogella.jersey.todo.Todo ; // Will map the resource to the URL todos @Path ( "/todos" ) public form TodosResource { // Allows to insert contextual objects into the grade, // e.g. ServletContext, Request, Response, UriInfo @Context UriInfo uriInfo ; @Context Request request ; // Return the list of todos to the user in the browser @GET @Produces ( MediaType . TEXT_XML ) public List < Todo > getTodosBrowser () { Listing < Todo > todos = new ArrayList < Todo >(); todos . addAll ( TodoDao . instance . getModel (). values ()); return todos ; } // Return the listing of todos for applications @Go @Produces ({ MediaType . APPLICATION_XML , MediaType . APPLICATION_JSON }) public List < Todo > getTodos () { Listing < Todo > todos = new ArrayList < Todo >(); todos . addAll ( TodoDao . example . getModel (). values ()); render todos ; } // retuns the number of todos // Apply http://localhost:8080/com.vogella.jersey.todo/remainder/todos/count // to go the full number of records @Go @Path ( "count" ) @Produces ( MediaType . TEXT_PLAIN ) public String getCount () { int count = TodoDao . instance . getModel (). size (); render String . valueOf ( count ); } @Post @Produces ( MediaType . TEXT_HTML ) @Consumes ( MediaType . APPLICATION_FORM_URLENCODED ) public void newTodo ( @FormParam ( "id" ) String id , @FormParam ( "summary" ) String summary , @FormParam ( "description" ) String description , @Context HttpServletResponse servletResponse ) throws IOException { Todo todo = new Todo ( id , summary ); if ( description != null ) { todo . setDescription ( clarification ); } TodoDao . instance . getModel (). put ( id , todo ); servletResponse . sendRedirect ( "../create_todo.html" ); } // Defines that the next path parameter after todos is // treated equally a parameter and passed to the TodoResources // Allows to blazon http://localhost:8080/com.vogella.jersey.todo/remainder/todos/1 // 1 will be treaded as parameter todo and passed to TodoResource @Path ( "{todo}" ) public TodoResource getTodo ( @PathParam ( "todo" ) String id ) { return new TodoResource ( uriInfo , request , id ); } } This TodosResource uses the @PathParam annotation to define that the id is inserted as parameter.
9.4. Run
Run your web application in Eclipse and examination the availability of your Balance service under:
http://localhost:8080/com.vogella.jersey.todo/rest/todos
Yous should encounter the XML representation of your TODO items.
To run across the count of TODO items use
http://localhost:8080/com.vogella.bailiwick of jersey.todo/rest/todos/count
to meet an existing TODO use
http://localhost:8080/com.vogella.bailiwick of jersey.todo/balance/todos/{id}", due east.thousand., http://localhost:8080/com.vogella.jersey.todo/rest/todos/ane to run across the TODO with ID 1. We currently have only TODOs with the ids 1 and two, all other requests will consequence in an HTTP error lawmaking.
Delight note that with the browser you tin merely issue HTTP GET requests. The adjacent chapter will use the Jersey client libraries to consequence get, mail service and delete.
9.5. Create a client
To test your service you can create a new course in your server projection. This project has already all required libs in the classpath, then this is faster than creating a new project.
Create the following class.
package com.vogella.jersey.todo ; import java.net.URI ; import javax.ws.rs.client.Customer ; import javax.ws.rs.client.ClientBuilder ; import javax.ws.rs.client.Entity ; import javax.ws.rs.client.WebTarget ; import javax.ws.rs.core.Form ; import javax.ws.rs.core.MediaType ; import javax.ws.rs.core.Response ; import javax.ws.rs.core.UriBuilder ; import org.glassfish.jersey.client.ClientConfig ; import com.vogella.jersey.todo.Todo ; public class Tester { public static void main ( Cord [] args ) { ClientConfig config = new ClientConfig (); Client customer = ClientBuilder . newClient ( config ); WebTarget service = customer . target ( getBaseURI ()); // create one todo Todo todo = new Todo ( "iii" , "Blabla" ); Response response = service . path ( "rest" ). path ( "todos" ). path ( todo . getId ()). request ( MediaType . APPLICATION_XML ). put ( Entity . entity ( todo , MediaType . APPLICATION_XML ), Response . class ); // Render code should be 201 == created resources System . out . println ( response . getStatus ()); // Become the Todos System . out . println ( service . path ( "residual" ). path ( "todos" ). request (). accept ( MediaType . TEXT_XML ). become ( String . class )); // // Get JSON for application (Make sure to add together the jersey-media-json-jackson dependency to add support for JSON) // System.out.println(service.path("rest").path("todos").request().accept(MediaType.APPLICATION_JSON).get(String.form)); // Become XML for application System . out . println ( service . path ( "rest" ). path ( "todos" ). request (). accept ( MediaType . APPLICATION_XML ). get ( Cord . grade )); //Get Todo with id 1 Response checkDelete = service . path ( "rest" ). path ( "todos/1" ). request (). have ( MediaType . APPLICATION_XML ). get (); //Delete Todo with id 1 service . path ( "rest" ). path ( "todos/1" ). asking (). delete (); //Get get all Todos id 1 should exist deleted Arrangement . out . println ( service . path ( "rest" ). path ( "todos" ). request (). take ( MediaType . APPLICATION_XML ). get ( Cord . form )); //Create a Todo Form grade = new Course (); course . param ( "id" , "iv" ); course . param ( "summary" , "Demonstration of the customer lib for forms" ); response = service . path ( "rest" ). path ( "todos" ). request (). post ( Entity . entity ( form , MediaType . APPLICATION_FORM_URLENCODED ), Response . class ); System . out . println ( "Form response " + response . getStatus ()); //Get all the todos, id 4 should have been created Arrangement . out . println ( service . path ( "rest" ). path ( "todos" ). request (). accept ( MediaType . APPLICATION_XML ). get ( String . class )); } individual static URI getBaseURI () { return UriBuilder . fromUri ( "http://localhost:8080/com.vogella.jersey.todo" ). build (); } } nine.6. Using the Residue service via HTML page
The above instance contains a form which calls a postal service method of your residual service.
How To Use Rest Services In Java,
Source: https://www.vogella.com/tutorials/REST/article.html
Posted by: powellreadeary.blogspot.com
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