Apart from the preceding approach, you can use a simplified version of the client API available on the Invocation.Builder object, such as head(), get(), post(), update(), put(), or delete(), to invoke the appropriate REST API. The following code snippet invokes the HTTP GET method on the department resource API in a more simplified way:

// Obtain a client reference 
Client client = javax.ws.rs.client.ClientBuilder.newClient(); 
// Bind the target to the REST service 
String BASE_URI =  
  "http://localhost:8080/rest-chapter3-service/webresources"; 
WebTarget  resource = client.target(BASE_URI).path("departments"); 
GenericType responseType=new GenericType<List<Department>>() { }; 
// Invoke GET  method on the resource 
List<Department> depts = 
   resource.request(javax.ws.rs.core.MediaType.APPLICATION_JSON).
     get(responseType);

The following code snippet illustrates how you can invoke the PUT method on a REST resource. This example updates the Department resource and posts the modified content to the RESTful web API:

departments/{id}. } 
//Get the modified department object   
Department department = getModifiedDepartment(); 
String id = department.getDepartmentId(); 
Client client = javax.ws.rs.client.ClientBuilder.newClient(); 
String BASE_URI =  
  "http://localhost:8080/rest-chapter3-service/webresources"; 
WebTarget resource = client.target(BASE_URI).path("departments") 
  .path(java.text.MessageFormat.format("{0}", new Object[]{id})); 
Builder builder =   
  resource.request(javax.ws.rs.core.MediaType.APPLICATION_JSON); 
//Invoke PUT method on resource to update the contents on server 
builder.put( javax.ws.rs.client.Entity.entity(department, 
  javax.ws.rs.core.MediaType.APPLICATION_JSON));