97 Things Every Java Programmer Should Know

Chapter 72. Refactoring Toward Speed-Reading

Benjamin Muskalla

A casual reader usually reaches 150–200 wpm (words per minute) with a good comprehension rate. People who are into speed-reading can easily reach up to 700 wpm. But don’t worry, we don’t need to set a new world record for speed-reading to learn the basic concepts and apply them to our code. We’ll look at three areas that are particularly helpful when it comes to reading code: skimming, meta guiding, and visual fixation.

So what makes speed-reading that fast? One of the first steps is to suppress subvocalization. Subvocalization? Exactly. That voice in your head that just tried to properly articulate that word. And yes, you’re now aware of that voice. But don’t worry, it will go away soon! Subvocalization can be unlearned and is an essential first step to seriously improve reading speed.

Let’s look at this method with three parameters, which all need validating. One way to read the code is to follow where and how the input parameters are used:

public void printReport(Header header, Body body, Footer footer) {
  checkNotNull(header, "header must not be null");
  validate(body);
  checkNotNull(footer, "footer must not be null");
}

After locating header, we have to find the next parameter, body, which requires us to look down and left. We can start with a simple refactoring to align the first and third check so we only break ...