JAVA
Lesson 2: Control Flow
Basic
how to make a good decision?
if Statement
boolean isRaining = true;
if(isRainging){ //if isRaining true, operate this scope
System.out.println("Close the window");
}
//if not nothing
else Statement
boolean isRaining = true;
if(isRaining){
System.out.println("Close the window");
}
else{
System.out.println("It's Sunny outside");
}
else-if Statement
int passcode = 555;
String coffeeType;
if(passcode == 555) {
coffeeType = "E";
} else if(passcode == 312) {
coffeeType = "V";
} else if(passcode == 629) {
coffeeType = "D";
} else{
coffeeType = "U"
}
System.out.println(coffeeType);
Boolean Expressions
boolean isLightGreen = 3>5;//This means false, so pass the scope
if(isLightGreen){
System.out.println("Drive!");
}
Logical Operators
- AND(&&) : true when all expressions are true.
-
OR( ) : true when one expressrion is true - NOT(!) : turns a value into its opposite
- the order of operations is
- Parenthese
- NOT
- AND
- OR
switch Statement
- switch
- case
- break : break out of each case
- default : typically comes at the end of a switch statement and its code will execute whenever the other cases aren’t met
int passcode =;
String coffeeType;
switch(passcode){
case 555: coffeeType = "E"; // :colon, not a semicolon
break;
case 312: coffeType = "V";
break;
case 629: coffeType = "D";
break;
default: coffeType = "U";
break;
}
System.out.println(coffeType);
I’m studing a “Java Programming Basics” @Udacity.