Conditional Execution - Building Java Programs: A Back to Basics Approach - page 267

Let's write our own version of the max method that returns the larger of two inte-
gers. Its header will look like this:
public static int max(int x, int y) {
...
}
We want to return either x or y , depending on which is larger. This is a perfect
place to use an if/else construct:
public static int max(int x, int y) {
if (x > y) {
return x;
} else {
return y;
}
}
This code begins by testing whether x is greater than y . If it is, the computer exe-
cutes the first branch by returning x . If it is not, the computer executes the else
branch by returning y . But what if x and y are equal? The preceding code executes
the else branch when the values are equal, but it doesn't actually matter which
return statement is executed when x and y are equal.
Remember that when Java executes a return statement, the method stops execut-
ing. It's like a command to Java to “get out of this method right now.” That means
that this method could also be written as follows:
public static int max(int x, int y) {
if (x > y) {
return x;
}
return y;
}
This version of the code is equivalent in behavior because the statement return x
inside the if statement will cause Java to exit the method immediately and Java will
not execute the return statement that follows the if . On the other hand, if we don't
enter the if statement, we proceed directly to the statement that follows it ( return y ).
Whether you choose to use the first form or the second in your own programs
depends somewhat on personal taste. The if/else construct makes it more clear that
the method is choosing between two alternatives, but some people prefer the second
alternative because it is shorter.
As another example, consider the indexOf method of the String class. We'll
define a variable s that stores the following String :
String s = "four score and seven years ago";