Update Java code to follow Java 8 syntax

[dutta14]

I wonder if it would be more beneficial for people to use Java 8 syntax for coding in interviews (many of them prefer it), and if so, if we should update our codebase to Java 8. I am up for making the changes.

[IAmPramod]

@dutta14 Are you working on this?
If yes, I would also like to contribute to this.

[dutta14]

Not yet. You can take it up if you're up for it.

[Aman199825]

hey I would like to work on changing the codebase to follow java 8 syntax.

[grgAditya]

still available?

[pavanp73]

Is it still available? Anyone working on this?

[vbhosle]

It would be better to provide Java 8 solution as an alternative than a replacement. People using this repo shouldn't be forced to learn Java 8. Sometimes code clarity can be lost in an attempt to make it shorter. In many organization Java 8 is still considered a plus point, not a must have skill. Having both would let people choose what they are comfortable with and also learn Java 8 comparatively.