You are allowed to put a label on any statement. Labels are given points in code mainly used along with goto in some other languages. Labels are rarely needed in Java, which lacks a goto statement like some other languages.

In java, labels are mainly used by break and continue statements which normally terminate or continue the innermost block.

There are three types of comments used in Java. These are single line comments, block comments and documentation comment. Also read why block comments might not always reliably comment out a section of code.

Charset is a combination of a coded character set and a character-encoding scheme. Here ‘set’ refers to the set of characters and their numbers (code points), and ‘encoding’ refers to the representation of these code points. We will also discuss common encoding related errors.

All Unicode characters can be used in comments, character and string literals in java. Unicode characters can be expressed through Unicode Escape Sequences. 

Unicode escape sequences consist of

Unicode is a computing industry standard for the consistent encoding, representation and handling of text expressed in most of the world's writing systems. The objective of Unicode is to unify all the different encoding schemes so that the confusion between computers can be limited as much as possible. Currently the Unicode standard defines values for over 100,000 characters.