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.
オブザーバオブジェクト
オブザーバが
Subject
をサブスクライ
ブ（
Subject
に登録）し、
Subject
の
データが変更されると更新情報を受信し
ます。
Subject
オブジェクトは重
要なデータを管理します。
S
u
b
j
e
c
t
オ
ブ
ジ
ェ
ク
ト
2
int
D
o
g
オ
ブ
ジ
ェ
ク
ト
M
o
u
s
e
オ
ブ
ジ
ェ
ク
ト
C
a
t
オ
ブ
ジ
ェ
ク
ト
新聞の定期購読について理解している場合、
Observer
パターンのことをかなり理解していることにな
ります。
Observer
パターンでは、発行者（パブリッシャ）は「サブジェクト」と呼ばれ、購読者（サ
ブスクライバ）は「オブザーバ」と呼ばれます。
詳しく調べてみましょう。
2
2
2
Subject
のデータが変更されると、オブ
サーバが通知されます。
データ値が変更されると、何
らかの方法で新しいデータ値
がオブザーバに通信されます。
D
u
c
k
オ
ブ
ジ
ェ
ク
ト
このオブジェクトはオブザー
バではないので、
Subject
の
データが変更されても通知さ
れません。
パブリッシャ＋サブスクライバ＝
Observer
パターン
2
章
Observer
パターン
you are here
45
Observer
パターン生活の
1
日
Duck
オブジェクトがやって来
て、「オブザーバになりたい」と
Subject
オブジェクトに言います。
Duck
は心から参加したがっていま ...
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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.