A conditional statement lets us choose which statement will be executed next • Therefore they are sometimes called selection statements • Conditional statements give us the power to make basic decisions • The Java conditional statements are the:
```
  – if statement
  – if-else statement
  – switch statement
```
# Boolean Notes
The Boolean logical operators are : | , & , ^ , ! , || , && , == , != .
Java supplies a primitive data type called Boolean, instances of which can take the value true or false only, and have the default value false.
The major use of Boolean facilities is to implement the expressions which control if decisions and while loops.

boolean isSoccerFan = true;//If you set a variable along with the word "boolean" to true, 
//this allows for the if statements to print the correct statements 
if(isSoccerFan){
    System.out.println("Watches 1 Soccer Game Every Weekend");
} else {
    System.out.println("Watches 0 Soccer Games");
}

Watches 1 Soccer Game Every Weekend

int weight = 200;
//Weights Are Rounded to Nearest 10(in pounds) between 130-250lbs
if(weight==130){
    System.out.println("Your Are Very Light");
}
else if(weight==140){
    System.out.println("Your Are Quite Light");
}
else if(weight==150){
    System.out.println("Your Are A Little Bit On The Lighter Side");
}
else if(weight==160){
    System.out.println("You Are At A Good Weight");
}
else if(weight==170){
    System.out.println("You Are At A Good Weight");
}
else if(weight==180){
    System.out.println("You Are At A Strong Weight");
}
else if(weight==190){
    System.out.println("You Are Very Close To Obese");
}
else if(weight==200){
    System.out.println("You Are Just Obese");
}
else if(weight==210){
    System.out.println("You Are Slightly Obese");
}
else if(weight==220){
    System.out.println("You Are Nearly Moderately Obese");
}
else if(weight==230){
    System.out.println("You Are Moderately Obese");
}
else if(weight==240){
    System.out.println("You Are Nearly Very Obese");
}
else if(weight==250){
    System.out.println("You Are Very Obese");
}

You Are Just Obese

Switch Statement Notes

A switch statement allows a variable to be tested for equality against a list of values.
Each value is called a case, and the variable being switched on is checked for each case.
The variable used in a switch statement can only be integers, convirtable integers (byte, short, char), strings and enums.
You can have any number of case statements within a switch.
End of each statement is followed with a comparable value and a colon.
The value for a case must be the same data type as the variable in the switch and it must be a constant or a literal.
When the variable being switched on is equal to a case, the statements following that case will execute until a break statement is reached.
When a break statement is reached, the switch terminates, and the flow of control jumps to the next line following the switch statement.

int weight = 200;
//Weights Are Rounded to Nearest 10(in pounds) between 130-250lbs. Intended for indivduals between the height of 5'8 to 5'11
switch(weight){
    
    case 130:
        System.out.println("You are Very Light");
         break;
    
    case 140:
        System.out.println("Your Are Very Light");
         break;
    
    case 150:
        System.out.println("Your Are A Little Bit On The Lighter Side");
         break;

    case 160:
        System.out.println("You Are At A Good Weight");
         break;

    case 170:
        System.out.println("You Are At A Good Weight");
         break;
    
    case 180:
        System.out.println("You Are At A Strong Weight");
         break;
    
    case 190:
        System.out.println("You Are Very Close To Obese");
         break;
    
    case 200:
        System.out.println("You Are Just Obese");
         break;

    case 210:
        System.out.println("You Are Slightly Obese");
         break;

    case 220:
        System.out.println("You Are Nearly Moderately Obese");
         break;

    case 230:
        System.out.println("You Are Moderately Obese");
         break;

    case 240:
         System.out.println("You Are Nearly Very Obese");
          break;

    case 250:
        System.out.println("You Are Very Obese");
         break;
    
    default:
        System.out.println("Invalid Input")
         break;
}

You Are Just Obese

DeMorgan's Law Notes

DeMorgan’s laws were developed by Augustus De Morgan in the 1800s.
They show how to handle the negation of a complex conditional, which is a conditional statement with more than one condition joined by an and (&&) or or (||), such as (x < 3) && (y > 2).
Applying DeMorgan’s Laws to !(x < 3 && y > 2) yields !(x < 3) || !(y > 2) which means that this complex conditional will be true when (x >= 3 || y <= 2).
The negation modifies each conditional as shown below.
- < becomes >=
- "> becomes <="
- == becomes !=
- <= becomes >
- ">= becomes <"
- != becomes ==
not (a and b) is the same as (not a) or (not b). In Java this is written as !(a && b) == !a || !b
not (a or b) is the same as (not a) and (not b). In Java this is written as !(a || b) == !a && !b

public class DeMorgansLawExample {
  public static boolean exVarOne = true;
  public static boolean exVarTwo = false;

  public static void main(String[] args) {
    // The two boolean expressions below are equal
    if (!(exVarOne && exVarTwo)) {
      System.out.println("The boolean expression is true");
    } else {
      System.out.println("The boolean expression is false");
    }
    if (!(exVarOne || exVarTwo)) {
      System.out.println("The boolean expression is true");
    } else {
      System.out.println("The boolean expression is false");
    }
  }
}
DeMorgansLawExample.main(null)

The boolean expression is true
The boolean expression is false