Checkout codecademy first. They have a great system for teaching the introductory stuff. It's hands-on and well explained. Tutorialspoint also have a lot of good reference material. Also if you google 'Dzone core java refcard' you will find the best java cheet sheet in existence. That should get you started. What kind of stuff do you wanna make with Java? Sky's the limit but for web-apps check out the spring framework, in particular 'spring-boot' is hugely popular these days as it greatfly simplifies and speeds up developing Spring applications.
Yeah, a combination of codeacademy (to get the syntax and basic java priciples down), reading through the java books wiki (found here:https://en.wikibooks.org/wiki/Java_Programming) and then try a couple min projects and methods on your own. Then if you get stuck ask some clear, well written questions on stackoverflow.
