JAX-RS : Mapping of URL Using @Path Annotation in Jersey

JAXRS path param will be used for mapping of path variable with @Path annotation. In JAX-RS, mapping of URL or handler URL is very easy by using @Path annotation, and it can be used on either class level mapping or method level mapping or on both level mapping. If you map on both on class and method, class level value comes first and method level value comes later in the URL, and the combination of URLs must be unique throughout the application. If your mapping would not be unique it throws exceptions while start-up of application.

1. Maven dependency for Jersey API

You can choose version of jersey as per your choice.

   com.sun.jersey
   jersey-server
   1.9

2. @Path annotation on class

Jersey path annotation can be used to bind the path variable.

package com.mysoftkey.jaxrs;

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

/**
 * This Jersey implementation of service class is used to demonstrate to get values from path.
 * 
 * @author Ranjeet Jha
 *
 */
@Path("/path")
public class PathService {

	/**
	 * Service URL : http://localhost:8080/jersey/path
	 * @return
	 */
	@GET
	public Response getSimple() {

		return Response.status(200).entity("simple path parmeter example, when @Path not on method level, only on class level.").build();

	}

3. @Path annotation on Class and method both.

@Path("/path")
public class PathService {

	/**
	 * In this method , @Path is static i.e. /person.
	 * 
	 * http://localhost:8080/jersey/path/person
	 * @return
	 */
	@GET
	@Path("/person")
	public Response getPerson() {
		return Response.status(200).entity("with static Path i.e person").build();
	}
	
}

4. Dynamic value in Path Param

/**
 * In this method , @Path variable is dynamic at run time with string value.
 * 
 * http://localhost:8080/jersey/path/ranjeet
 * @return
 */
@GET
@Path("{name}")
public Response getUserByName(@PathParam("name") String name) {
	return Response.status(200)
		.entity("with dynamic path parameter, i.e. name : " + name).build();
}

Service URL : http://localhost:8080/jersey/path/ranjeet
Output :

 with dynamic path parameter, i.e. name : ranjeet

5. Dynamic value in Path param with RegEx as digit only

This method invoked when path variable i.e. id is numeric , so there can be a constraint applied with regular expression.

/**
  * In this method , @Path is dynamic at run time with constraint i.e. it can be only numeric not string.
  * It support digit only.
  *  
  * Service endpoint : http://localhost:8080/jersey/path/12
  * @return
  */
 @GET
 @Path("{id : \\d+}") 
 public Response invokeIfDigitInPath(@PathParam("id") int id) {
   return Response.status(200).entity("invoked when id is digit only, id : " + id).build();
}

Service URL : http://localhost:8080/jersey/path/12
output :

 invoked when id is digit only, id : 12

6. Dynamic Value in Path Param with RegEx as string

This method invoked when the name path parameter is string ( i.e. alphanumeric), so there can be a constraint applied by using a regular expression, it means, you can say, regular expression supported in jersey JAX-RS.

/**
 * In this method , @Path is dynamic at run time with constraint i.e. it can be only numeric not string.
 * 
 * Service end point : http://localhost:8080/jersey/path/regEx/ranjeet123
 * 
 * @param info
 * @return
 */
@GET
@Path("/regEx/{name : [a-zA-Z][a-zA-Z_0-9]}")
public Response invokedForInfo(@PathParam("name") String name) {
   return Response.status(200).entity(" Path with RegEx , name: " + name).build();
}

7. Download Source Code

Download source code of JAX-RS: Jersey @Path Example

8. References

for more details of jersey path annotation you can refer following link.

1. Jersey Official site
2. JAX-RS official site
3. Oracle Java Web services tutorial
4. Wikipedia

Happy learning for jaxrs path param by using @Path annotation in Jersey.