Java
TOPIC 14 – IF STATEMENTS – PART 1

AP EXTRA

AP LESSON NOTE

ONE LINE STATEMENT BLOCKS

We have seen examples with statement blocks that contain only one line. Here's an example:

if (mark < 50)

{

System.out.println("You are not passing.");

}

We can actually write such one-line statement blocks without the { and } brackets. So, the above could be re-written as:

if (mark < 50)

System.out.println("You are not passing.");

WARNING

Not using brackets can be risky. If you decide to add a line to the statement block, you then have a multi-line block which requires the { and } brackets.

Furthermore, it's important to realize that indenting has no impact on what statements are part of a statement block.

EXAMPLE

Let's assume we started with this program:

if (mark < 50)

System.out.println("You are not passing.");

And then we added another output statement that should be part of the statement block.

if (mark < 50)

System.out.println("You are not passing.");

System.out.println("You need to work harder.");

Now, the second output statement is not actually part of the statement block. It is actually after the if-statement and will be executed every time. The correct version of the above program would be:

if (mark < 50)

{

System.out.println("You are not passing.");

System.out.println("You need to work harder.");

}