To write a user-oriented program (1)

What is a user-oriented program?

The system is still up and running today. Well, how about it? If I log in and operate a certain screen, I don't get a response ... If that happens.

There may be several implications for this.

--The program has not been processed --DB unresponsive, error due to memory exhaustion --Web server stopped due to the above cause --Hosting service failure, maintenance

And the worst is the pattern that was caused by the program I wrote.

Let's be able to write a user-oriented program so that it does not happen. That way, the program I wrote will always be alive. You can maintain a system that pleases your users.

(Private) Good program 3-piece set

--Short number of program lines --Processing time is short --Memory usage is optimized First of all, if you are aware of these three things, it will be a program that will not die in operation. Also when code review and refactoring I think that having this perspective will make the program better.

Shorten the processing time

Use StringBuilder instead of String when concatenating characters

When stringing with String


String name = "Quokka";
name += "Wallaby";
name += "Mr";

At compile time


String name = new StringBuilder("Quokka").toString();
name += new StringBuilder(name).append("Wallaby").toString();
name += new StringBuilder(name).append("Mr").toString();

As you can see, each object is created in vain. In other words, memory usage will increase temporarily.

Suddenly out of memory

Our battle is about to begin ...! I'll let you continue next week.

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