Java operator Note points

==
(1) If the two operands of the comparison are numeric types, even if the types are different, as long as the values are equal, true if (1 = 1.0) True if (' A ' = +) True
(2) Two operands are reference types, the two reference types must have an inheritance relationship before they can be compared, and only two reference variables point to the same entity is true

(3) Basic data type, literals cannot be compared with variables of reference type

！ = attention point Reference = =

The difference between & and &&:& always executes the first two operands before the logical,&& calculates the left operand first, and if it is false, no longer evaluates to the right and returns false

The difference between I and II is on the reference.

Java operator Note points