Language Fundamentals

Language Fundamentals

1. encoding sets

   • ASCII
     • alphanumeric characters: lower case, uppercase Latin letters, #s, and punctuation
     • extended has another 128 characters
   • unicode
     • includes all characters in all languages into one single chacater set
     • not efficient in storing and transmitting
       • UTF-8
       • UTF-16
       • UTF-32

2. primitives

   • integers
     • byte, 8 bits
     • short, 16 bits
     • long, 64 bits
     • int, 32 bits
   • decimals
     • float, 32-bit
     • double, 64 bit
   • char, unicode character
   • boolean, true/false

3. variables

   • reference type
   • primitive type
   • identifier
     • begins with java letter
     • can't be a java keyword
     • unique within its scope

4. constants, variables with unchangeable values

5. literals

   • primitive type literals
     • integer literals
       • assign values to variables of byte, short, int, and long
       • can't assign value that exceeds capacity of variable
     • floating-point literals
       • whole number part, decimal part, fractional part, optional exponent
       • absense of f_ or _F makes a float literal a double
     • character literals
       • unicode character
       • escape sequence enclosed in ' '
     • boolean literals
       • two value: true/false
   • string literals
   • null literal