June 2022
Beginner to intermediate
672 pages
17h 23m
Japanese
Content preview from Head Firstデザインパターン 第2版 ―頭とからだで覚えるデザインパターンの基本
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
you are here
413
10
章
State
パターン
ブラボ ー！
君たち最高
だよ。この新しいゲームのおかげでうちの
売上はもう絶好調だよ。うちはソーダマシン
も製造しているんだが、側面にスロットマシン
のアームを取り付けて、ソーダマシンもゲーム
にできないかと考えている。うちはガムボール
マシンで
4
年間ギャンブルをしてきたんだ。
ここで止める手はないだろう？
健全性チェック
Mighty Gumball
社の
CEO
にも健全性チェックが必要でしょうが、ここで話した
いのはそのことではありません。この優れたバージョンのマシンを出荷する前に、
GumballMachine
の改善したいいくつかの側面について考えてみましょう。
●
Sold
状態と
Winning
状態に多くの重複コードがあるので、整理し
たいと思います。どうすればよいでしょうか？
State
を抽象クラス
に入れて、メソッドのデフォルトの振る舞いを組み込むことができ
ます。結局、「すでに
25
セントを投入しています」などのエラーメッ
セージは客からは見えません。したがって、すべての「エラー応答」
の振る舞いは、抽象クラスから継承した汎用的なものにできます。
●
25
セントが未投入のままハンドルを回したとしても、
dispense()
メ
ソッドは必ず呼び出されます。マシンが正しく動作していれば、正
しい状態でなければガムボールは出ないので、
turnCrank()
がブー
ル値を返すようにするか例外を導入すれば、簡単に修正できます。
どちらが優れた解決策だと思いますか？ ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.