Kev-in123

Access Control:
  private - can only be accessed in the class
  protected - can only be accessed in the class or a subclass
  public - can be accessed anywhere

Modifiers:
  abstract -  a non-access modifier, used for classes and methods
  final - a non-access modifier used for classes, attributes and methods (not changeable)
  finally - executes no matter if the try-except failed or passed
  native - specifies that a method is not implemented in the same java source file

Kev-in123

Data types (probably useless but since there is a coding portion, I'm including them anyways):
  boolean - stores true or false
  byte - stores whole numbers from -128 to 127
  char - stores a single character/ASCII values
  int - stores whole numbers from -2,147,483,648 to 2,147,483,647
  long - stores whole numbers from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
  short - stores whole numbers from -32,768 to 32,767
  float - stores fractional numbers, sufficient for storing 6 to 7 decimal digits
  double - stores fractional numbers, sufficient for storing 15 decimal digits

Kev-in123

Non-numerical math values in java:
  n/0.0 = Infinity where n is a positive number
  n/0.0 = -Infinity where n is a negative number 
  0/0.0 = NaN (can also do 0.0/0.0)
  note the 0.0 is a decimal and not an integer

Operators:
  + adds the numbers
  - subtracts the numbers
  * multiplies the numbers

Kev-in123

public class ArrayExamples {
  public static void main(String[] args) {
    // create an array of integers of length 10
    int[] arr = new int[10];
    // store the size of the array in a variable
    int len = arr.length;
    // use a for-each loop to 
    for (int i: arr) {
      System.out.println(i);
      // the output will be 10 lines of 0s since we haven't modified it

Kev-in123

//Some of these may have errors as i was too lazy to check if they work or not
//Recursion exsists in java but i'm not adding them in these notes

public class MethodExamples {
    //the main method, the entry point of the program
    //methor name: main
    //return type: N/A
    //parameters: String[] args
    public static void main(String[] args) {
          System.out.println("Hello World");

Kev-in123

|| - or
&& - and
! - not

switch - The expression is compared with the values of each case, if none match, then the default is used, if there isn't a default, nothing happens
case - Used in a switch-case statement to specify a case
default - The default block of code in a switch statement, if it's the last statement, it doesn't need a break

Notes on switch-case statements:
  - The variable used in a switch statement can only be an integer/byte/short/char/strings/enums