index.md

Comments

Comments allow us to add non code descriptions and text to help better read the code.

// Single line comment  
/*  
 \* Multi  
 \* line  
 \* comment  
 \*/

Variables

int iAmInt = 5;  
boolean iAmBool = true  
String iAmString = "this is a string"

Functions/Scope

Functions let use define reuseable bits of code.

function to add two numbers

static int sum(int x, int y) {
    return x + y;
}

Control statements

IF

if(BOOLEAN_VALUE) {
    // if BOOLEAN_VALUE was true
} else {
    // if BOOLEAN_VALUE was false
}

SWITCH

switch(expression){    
    case value1:    
        // code to be executed;    
        break;  // optional  
    case value2:    
        // code to be executed;    
        break;  // optional
    default:     
        // Any other value  
}  

EXCEPTIONS (ERRORS)

When calling a method, sometimes it fails with an error. In Java we call this an exception. If we want to be able to do something with an exceptions (handle the exception), we use a try/catch block.

try {
    // Code that might throw an exception
} (Exception ex) {
    // If the above had an error, we will run the code here.
}