Learning Java

Access identifiers

Constructors

is a marker for a statement. E.g. label :

a high-level instruction e.g. x=x+1

is a pair of curly brackets enclosing one or more statements

Operators

Use operator new to create a new instance of an object; binary operator instanceof to test whether the specified class or one of its subclasses

Array storage and initialization

Array dimensions

requires one bit of space

Character types

2 types: float(32 bits) and double(64 bits). Value is NaN (not a number) when it's overflow or underflow

Wrap around of an integer value

Unlike the Integer class, there is no behavior associated with it. It has 4 types: byte(8 bits), short(16 bits), int(32 bits), long(64 bits). It is signed - contains both positive and negative values

Base - cannot be broken down: integer, floating point, character, boolean Composite - arrays, classes, interfaces

In the methods, variable this is used to refer to the class itself, not the local variable in the method

each has 16 bits and is sufficient to handle most of the world's languages