Java is such a versatile language. You can make your own methods, or groups of commands executable whenever you call it. Imagine if you could call you could tell a robot to clean your room, make your bed, and fold your clothes with just one command: that's the power of the method in Java.
Structure:
accessLevel static/nonstatic returnType name(parameter type varName)
{
//enter code here
//possible return type
}
Note: Don't use the word "non-static" just leave this field empty; also void means no return type
public void printDifference(int large, int small)
{
System.out.println(large-small);
}
public static int sum(int a, int b)
{
int sum = a+b;
return sum;
}
Why Use Methods?
Methods allow the user to call a function multiple times without having to write the code multiple times, decreasing the length of the program: readability. Furthermore, methods allow the programmer to change parts at one place, rather than at each instance of the function call: maintainability.
Selection Statements:
There are three major selection statements: if, else if, and else.
Essentially, a boolean expression is placed within parenthesis, leading the computer to decide whether to execute the following set of commands.
Note: modulus(%) returns the remainder
Examples:
int x = 4;
if(x%2==0)
System.out.println(x+" is odd.");
else if(x==0)
System.out.println("you entered 0.");
else
System.out.println(x + "is even.");
//output - 4 is odd; computers do what they tell you to do - they aren't that smart. Read carefully!
Note: brackets are not required if the statement is only one line, however, if there are multiple lines then you have to add brackets.
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