Method Signature Example: Reading public static int add

Five decisions packed into one line, each word answering one question.

A method's declaration line says who may call it, whether it needs an object, what it returns, what it is called and what it needs, in that order. One line from a real class, read left to right:

java

public static int add(int a, int b) {
    return a + b;
}

Each part of the signature, and the question it answers
Part	Question it answers
`public`	Who may call it
`static`	Does it belong to the class rather than to one object
`int`	What does it hand back
`add`	What do callers write
`(int a, int b)`	What must callers supply, and in what order

Two of those are worth reading carefully. The return type is a promise: declaring int means every path through the body has to end in a return of an int, and the compiler checks every path. Declaring void means the opposite promise: the method produces nothing, and return someValue; inside it will not compile.

Notice that the parameter list is the only part that decides which method a call matches. The return type is not part of that decision at all.

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