REST WEBSERVICE - JERSEY CLIENT API
Jersy is a Open Source Implementation of JAX-RS used to create RESTful Webservices using Java.
import com.sun.jersey.api.client.Client;
Client client = Client.create();
creating a instance of a Client is an expensive operation so re-use it after initializing for the first time.
create a WebResource object, which encapsulates a web resource for the client.
import com.sun.jersey.api.client.WebResource;
WebResource webResource = client.resource("http://example.com/base");
use WebResource object to build requests to send to the web resource and to process responses returned from the web resource. For example, you can use the WebResource object for HTTP GET, PUT, POST, and DELETE requests.
String s = webResource.get(String.class);
Download Jersey Resource bundle Jersey-bundle and add jars to the classpath.
public String sendRestRequest(String restUrl) {
String response = null;
Client client = Client.create();
WebResource webResource = client.resource(restUrl);
// response type returned from the REST resource is XML or JSON
ClientResponse clientResponse = webResource.accept(MediaType.APPLICATION_JSON_TYPE, MediaType.APPLICATION_XML_TYPE).get(ClientResponse.class);
try {
// If status code returned is not 200 throw error
if (clientResponse.getStatus() != 200) {
System.out.println(" \n Rest URL : " + restUrl +
" Failed with HTTP error code : " +
clientresponse.getStatus());
return null;
}
response = clientResponse.getEntity(String.class);
} catch (Exception e) {
e.printStackTrace();
}
// JSON response
return response;
}
How to pass authentication parameters along with Client request
import com.sun.jersey.api.client.filter.HTTPBasicAuthFilter;
use HTTPBasicAuthFilter to pass username and password.
HTTPBasicAuthFilter authFilter =
new HTTPBasicAuthFilter(username, pwd);
client.addFilter(authFilter);
WebResource webResource = client.resource(restUrl);
How to pass Custom Headers along with client request
ClientResponse clientResponse = webResource.accept(MediaType.APPLICATION_JSON_TYPE, MediaType.APPLICATION_XML_TYPE).header("Custom-header",headerValue).get(ClientResponse.class);
