Java Language fundamentals

Java Language fundamentals

1. Encoding Sets

   • ASCII
     • 128 characters, common in English speaking countries
   • Unicode
     • Character set containing all characters from all languages

2. Primitives

   • Byte: -128 - 127
   • Short: -32768 - 32767
   • Int: -2^31 - (2^31 - 1)
   • Long: -2^63 - (2^63 - 1)
   • Float: single-precision floating point decimal number
   • Double: double-precision floating point decimal number
   • Char: a unicode character
   • Boolean: True or False

3. Constants

   • Variables whose values, once assigned, can not be changed
   • Constants are declared with keyword "final"

4. Literals: a sequence of characters (digits, letters, and other characters) that represent constant values to be stored in variables

   • Integer Literals
   • Floating-point Literals
   • Boolean Literals
   • Character Literals

5. Variables

   • Reference types: variables that provide reference to an object
   • Primitive types: variables that hold a primitive
   • Must be declared before they can be used