To make a GET request to an RQM server you need to set four HEADER values
Authorization: Basic BASICAUTHTOKEN
The generate the BASICAUTHTOKEN, perform the following operation [credit]
String userpass = username + ":" + password;
String basicAuth = "Basic " + javax.xml.bind.DatatypeConverter.printBase64Binary(userpass.getBytes());
The endpoint will look something like this
Here is the cURL version of my Postman
curl -X GET -H "Accept: application/xml" -H "Content-Type: application/rdf+xml" -H "OSLC-Core-Version: 2.0" -H "Authorization: Basic BASICAUTHTOKEN" -H "Cache-Control: no-cache" "https://jazz.net/sandbox01-qm/process/project-areas"