JAX-RS @Produces with Example – RESTful Web Services Tutorial

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In JAX-RS @Produces annotation is used to specify the MIME media type ( output ) that a resource method can produce and send it back to the client.

@Produces annotation can be applied at both class level and method level. If it is applied at the class level, all the methods in a resource will produce the specified MIME type by default and if it is applied at the method level, then annotated method will produce the specified MIME type by overriding any @Produces annotations applied at the class level.

If any method in a resource is not able to produce the specified MIME type, then Jersey runtime sends back an HTTP “406 Not Acceptable” error to the client.

The value of @Produces annotation is an array of String of MIME types. For example:

@Produces(MediaType.TEXT_PLAIN)
@Produces(MediaType.APPLICATION_JSON)
@Produces(MediaType.APPLICATION_XML)

Let’s try to understand it with an example.

Example 1 :-

In this example of JAX-RS @Produces, we will hit this URL <base URL>/books/1 with HTTP GET method to get the book resource of id 1 in plain text format. 

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

@Path("books")
public class ProducesAnnotationExample {

  @GET
  @Produces(MediaType.TEXT_PLAIN)
  @Path("/{id}")
  public Response getAllBooks(@PathParam("id") String bookId){
    return Response.status(200)
		   .entity("Book id is : " + bookId).build();
  }
	
}

Result :-

JAX-RS @Produces

Example 2 :-

Book.java

Create a bean class “Book” with few class members. This class will be used as an entity to send a response to client in JSON format. We also annotated our bean class with @XmlRootElement marking it as a root element, so that we can use same bean class to send a response to client in XML format.

import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement
public class Book {

  private String id;
	
  private String name;
	
  private String authorName;
	
  private int volumeNumber;
	
  public String getId() {
    return id;
  }
	
  public String getName() {
    return name;
  }
	
  public void setName(String name) {
    this.name = name;
  }
	
  public String getAuthorName() {
    return authorName;
  }
	
  public void setAuthorName(String authorName) {
    this.authorName = authorName;
  }
	
  public int getVolumeNumber() {
    return volumeNumber;
  }
	
  public void setVolumeNumber(int volumeNumber) {
    this.volumeNumber = volumeNumber;
  }	
	
}

Dependency

Add one dependency in pom file of your project. This dependency is required by jersey library to convert your bean class in to JSON format and vice versa.

<dependency>
    <groupId>org.glassfish.jersey.media</groupId>
    <artifactId>jersey-media-moxy</artifactId>
    <version>2.26-b03</version>
</dependency>

In this example of JAX-RS @Produces, we will hit this URL <base URL>/books/1 to get the book resource of id 1 in JSON format.

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

@Path("books")
public class ProducesAnnotationExample {

  @GET
  @Produces(MediaType.APPLICATION_JSON)
  @Path("/{id}")
  public Response getAllBooks(@PathParam("id") String bookId){
    Book book = new Book();
    book.setId(bookId);
    book.setName("Harry Potter");
    book.setVolumeNumber(1);
    book.setAuthorName("J. K. Rowling");
    return Response.status(200)
		   .entity(book).build();
  }
	
}

Result :-

JAX-RS @Produces

Example 3 :-

In this example of JAX-RS @Produces, we will hit this URL <base URL>/books/1 to get the book resource of id 1 in XML format.

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

@Path("books")
public class ProducesAnnotationExample {

  @GET
  @Produces(MediaType.APPLICATION_XML)
  @Path("/{id}")
  public Response getAllBooks(@PathParam("id") String bookId){
    Book book = new Book();
    book.setId(bookId);
    book.setName("Harry Potter");
    book.setVolumeNumber(1);
    book.setAuthorName("J. K. Rowling");
    return Response.status(200)
		   .entity(book).build();
  }
	
}

Result :-

JAX-RS @Produces

References :-

  1. @Produces Java Docs

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