Java Language Fundamentals

Java Language Fundamentals

1. Encoding Sets

   • Java supports the Unicode character encoding set, which is not limited to ASCII characters.

2. Primitives

   • Pre specified data types with a specific format and size
     • byte (-128 - 127)
     • short (-32,768 - 32,767)
     • int (-2^31 - 2^31 -1)
     • long (-2^63 - 2^63 -1)
     • float
     • double
     • char - unicode character
     • boolean - true or false

3. Variables

   • Data placeholders with a name and an identifier
     • Identifier: unlimited-length sequence of Java letters and Java digits

4. Constants

   • Variables whose values, once assigned, cannot be changed. Indicated by the keyword "final".

5. Literals

   • Null literal
   • String literal
   • Primitive literals
     • Integer literals
       • used to assign values to variables of types byte, short, int, and long
     • Floating point literals
       • float and double
       • a number that has a whole number part, a decimal point, a fractional part, or an optional exponent
     • Character literals
       • a Unicode character or an escape sequence in single quotes
     • Boolean literals
       • represented by true and false

6. Primitive conversion

7. Operators

8. Separators

   • Special characters Java uses as separators in the language and flow of code
     • Parentheses ()
       • Used for
         • method signatures to contain lists of arguments
         • expressions to raise operator precedence
         • narrowing conversions
         • loops to contain expressions for evaluation
     • Braces {}
       • Used for
         • declaration of types
         • blocks of statements
         • array initialization
     • Brackets []
       • array declaration
       • array value dereferencing
     • Semicolon ;
       • Used to end statements and in for statements to seperate
     • Colon :
       • used in for statements that iterates over an array
     • Comma ,
       • used to separate arguments in method declarations
     • Period
       • separate package names, fields, and methods from reference variables