Book

Text Book

https://freepdf-books.com/download/?file=13615

Core Java  Vol-1 10 Edt.

Core Java Vol-II 10 edt

https://archive.org/details/CoreJava2CVolumeIIAdvancedFeatures2CayS.Horstmann/mode/2up


Java: The complete Reference 

Reference:
https://www.docdroid.net/mY1yTPu/advancedjavaprogrammingbyuttamkumarroy.pdf