Java Basics - Functions 2

Parameters and Arguements.

Parameters are variables in the parentheses of our function defintion, that we can be used inside a function.

 For example:

 public void greeting(String location){
        //greet a specific location
        System,out.println("Hello, " + location);
}
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 Arguments are specific values passed into our function call.

 For example: 

 greeting("Australia");

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How to list multiple parameters in a function:

 For example: 

 public void boxVolume (int height, int width, int depth){
//Code goes here
}
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 Return Values
In the following example:  public void functionName(). The void (return type) means not returning any data  outside the function  we can only complete an action.

 In the following example: public boolean functionName(). The boolean means we can return a boolean value outside the function definition

To return any data, we need to change the return type (like done above) and have a return statement..

For example;
public int randomFunction(int denisty){
//execute code
return size;
}

Now we can store the data in a variable for example.

int randomVariable = randomFunction(50);

 As you can see the return value lets you use values in other function calls or programs.
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