DesignOfEverydayThings - What I learned as a developer

In this series of notes:  https://twitter.com/ajavadeveloper/status/1145615948277112833

I only notes part of "Fundamental Principles of Interaction"

It's just a small unit of this book, but already help me A LOT.

Whenever I'm confused of designing, I re-read this book to get more ideas.

Because I'm a developer, so the most important thing it taught me is:

Why we need write clean code, how a clean code look like? How to know a design is good or bad.

• Affordance and Signifier: That's why we need good naming.
• Ex. visible signifier

StringUtils.trimToEmpty

StringUtils.substringBetween

• Ex. Invisible

String dateString = PrivateDateUtils.toDateString( date ); // What is the format?

@SuperAnnotation // Things become invisible when there are many decision made at runtime, developer won't know.

public class NormalClass {}

• Mapping and Conceptual Models: Developers always handling mapping and conceptual models

PersonDao.persist( person ); // Clear model, dev expect it will persist

Person.save(); // May be a little confuse

personService.find( id ); // When a find method persist data due to other reason such as queue full or statistics, it become confusing

• Feedback: We need many feedback, no matter in code or in performance tunning or monitoring

personService.find( id ); // It's better to response quickly

personService.find( id, timeout, TimeUnit ); // It's better to provide timeout when things may become long

public void find(String id) {

    try {

        personDao.someErrorMayHappen(); 

    } catch (Exception ex) {
        // Eveything is find, treat as no data

    }

}

• When there are too many error, we even unable to know the feedback is valid or not