String rabbitmqHost = "192.168.0.100";
String rabbitmqPort = "15672";
String userName = "xxxx";
String password = "password";

String url = String.format("http://%s:%s/api/overview",rabbitmqHost,rabbitmqPort);


BASE64Encoder base64Encoder = new BASE64Encoder();
String base64Str = String.format("%s:%s",userName,password);
String base64Val = base64Encoder.encode(base64Str.getBytes());

Map<String,String> headerMap = new HashMap<>();
String authHash = String.format("Basic %s",base64Val );
headerMap.put("authorization",authHash);