Unable to get response from JAX-RS endpoint with ajax [duplicate] - ajax

Question

While sending a post request from my tomcat web service i got an error as below:
" Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'null' is therefore not allowed access."
I'm using tomcat 9.* and developed my web service with jax-rs java web api.
While i have tested my web service with postman, i got a good response from my web service (http 200 response). Yet, when i tried to send ajax post request i got the message above. I tried to enable the CORS filter and tried to send get request that working fine..
the web.xml:
<filter>
<filter-name>CorsFilter</filter-name>
<filter-class>org.apache.catalina.filters.CorsFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>CorsFilter</filter-name>
<url-pattern>/*</url-pattern>
<dispatcher>FORWARD</dispatcher>
</filter-mapping>'
the jax-rs post function:
#POST
#Path("/users2")
#Consumes("application/json")
#Produces(MediaType.APPLICATION_JSON)
public Response SetAllTlcsStatus(List<TrafficLight> c){
System.out.println("You have entered the SetTlc function");
return Response.ok() //200
.header("Access-Control-Allow-Origin", "*")
.header("Access-Control-Allow-Methods", "GET, POST, DELETE,
PUT")
.allow("OPTIONS").build();
}
the ajax request:
$.ajax({
type : "POST",
url : "http://localhost:8080/userManagement/rest/Traffic/users2",
contentType :"application/json; charSet=UTF-8",
data : d,
dataType : "json",
beforeSend: function (xhr){
console.log('Before');
xhr.setRequestHeader('Authorization', make_base_auth(user, pass));
}'

Answer 1

You say "I tried to enable the CORS filter and tried to send get request that working fine."
Do you mean that GET method works but POST not? If so you must allow it on your REST service/terminal and also these settings
header("Access-Control-Allow-Origin", "*")
header("Access-Control-Allow-Methods", "GET, POST, DELETE, PUT")
Finally, if by any chance your AJAX still returns failed try
$.ajax({
type : "POST",
url : "http://localhost:8080/userManagement/rest/Traffic/users2",
contentType :"application/json; charSet=UTF-8",
data : d,
dataType : "json",
**xhrFields: {
withCredentials: true
},
crossDomain: true,**
beforeSend: function (xhr){
console.log('Before');
xhr.setRequestHeader('Authorization', make_base_auth(user, pass));
}'