In the below screenshot containing code for adding elements to a `List`, the instance variables are being initialized in a way I haven't come across before. I have tried to do the same in eclipse but was unable to replicate it. I understand initializing variables via constructor in this way - 

```
new Potus("Donald","Trump",2016,"Republican") 

```

but this way - 

`new Potus(firstName:"Donald",lastName:"Trump",electionYear:2016,party:"Republican")` 

is something new for me. I do not have the source code as well as its not available for download. Can you please let me know which is the topic it comes under or provide me any reference. Thanks in advance for your help.

[![enter image description here](https://i.stack.imgur.com/XFIYm.jpg)](https://i.stack.imgur.com/XFIYm.jpg)