Create a REST service in Java using JAX-RS and Eclipse

In this article, I will be demonstrating creating a REST service in Java using JAX-RS and Eclipse. I will be using Maven and Eclipse.

Create a Project and And Maven Support

Step 1 – Follow the steps in this article to create a web project in Eclipse with Maven Support. You should see a project as follows:

Step 2 – Add Maven dependencies for JAX-RS and Jersey as follows:

<dependency>      <groupId>asm</groupId>      <artifactId>asm</artifactId>      <version>3.3.1</version>    </dependency>    <dependency>      <groupId>com.sun.jersey</groupId>      <artifactId>jersey-bundle</artifactId>      <version>1.19.4</version>    </dependency>    <dependency>      <groupId>org.json</groupId>      <artifactId>json</artifactId>      <version>20170516</version>    </dependency>    <dependency>      <groupId>com.sun.jersey</groupId>      <artifactId>jersey-server</artifactId>      <version>1.19.4</version>    </dependency>    <dependency>      <groupId>com.sun.jersey</groupId>      <artifactId>jersey-core</artifactId>      <version>1.19.4</version>    </dependency>

 

Modify web.xml

In the WebContent/WEB-INF/web.xml file, add the following content:

<servlet>   <servlet-name>LearnJava JAX-RS Jersey Application</servlet-name>   <servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>   <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping>   <servlet-name>LearnJava JAX-RS Jersey Application</servlet-name>   <url-pattern>/learnjava/*</url-pattern> </servlet-mapping>

Add Code

Create a new class in src called HelloWorldService as follows:

@Path("/hello")public class HelloWorldService {    @GET  @Produces("text/plain")  public String getGreeting() {    return "Hello World!";  }}

Compile

Step 1 – Right Click on Project –> Run As –> Maven Build

Step 2 – If prompted, enter the goals as Clean Install

Deploy

Step 1 – Setup Tomcat in Eclipse if nor already setup. Refer to this blog post for detailed steps

Step 2 – Deploy your application to Tomcat. Refer to this blog post for detailed steps.

Test

Testing Via Browser

Open a browser window and type the following URL:

http://localhost:8080/LearnJavaRestJAXRSJerseyDemo/learnjava/hello

This will display the following page:

Conclusion

So this is how you can create a REST service in Java using JAX-RS and Eclipse.

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