導入The enterprise Java community exerts a lot of effort toward wiring objects together. How does your web application get access to a middle tier service, or your service to the logged in user or transaction manager? You'll find many gene…

Guiceを使ったDependency Injection（依存性の注入）Writing factories and dependency injection logic by hand for every service and client can become tedious. Some other dependency injection frameworks even require you to explicitly map servic…

手作業でのDependency InjectionThe dependency injection pattern aims in part to make unit testing easier. We don't necessarily need a specialized framework to practice dependency injection. You can get roughly 80% of the benefit writing cod…

BENCHMARK関数が、SQLのパフォーマンスチューニングに便利だ。「5.2. SELECT ステートメントおよびその他のクエリの最適化」 mysql> SELECT BENCHMARK(1000000,1+1); + BENCHMARK(1000000,1+1) + 0 + 1 row in set (0.32 sec)これは、PentiumII 400MHz 上で …

プレーン・オールド・ファクトリーBefore we discovered dependency injection, we mostly used the factory pattern. In addition to the service interface, you have a service factory which provides the service to clients as well as a way for test…

Guice 1.0 User's GuideGuice (pronounced "juice") is an ultra-lightweight, next-generation dependency injection container for Java 5 and later.Guiceは、超軽量の次世代Dependency Injectionコンテナで、Java 5以降で動きます。 id:shot6さんが一覧…

よく忘れるので記録。ユーザー・パスが以下の場合 user: root pass: root 以下のコマンドで、すべてのデータベースのDumpスクリプトが保存される。 mysqldump -A -u root -proot -Q --opt -r c:\mysql.dump復元は以下。 mysql -u root -proot test mysql.dump

Group By 節に含まれないカラムをSelect句で表示するとmin(カラム)と同じ結果になる。 MySQLのリファレンス「■6.3.7.3. 非表示のフィールドに対する GROUP BY」より MySQL では GROUP BY の使用を拡張しています。GROUP BY 部分にないカラムや計算を SELECT …

実行時We can now use the injector we created during the first stage to inject objects and introspect on our bindings. Guice's runtime model consists of an injector which contains some number of bindings.これで、オブジェクトを注入したり、バ…

起動時You configure Guice by implementing Module. You pass Guice a module, Guice passes your module a Binder, and your module uses the binder to configure bindings. A binding most commonly consists of a mapping between an interface and a c…

アーキテクチャの概要We can break Guice's architecture down into two distinct stages: startup and runtime. You build an Injector during startup and use it to inject objects at runtime.Guiceのアーキテクチャは、2つの別々のステージに分離するこ…

その他のアノテーションWhen possible, Guice enables you to use annotations in lieu of explicit bindings and eliminate even more boilerplate code. Back to our example, if you need an interface to simplify unit testing but you don't care abou…

Guice vs. お手製DIAs you can see, Guice saves you from having to write factory classes. You don't have to write explicit code wiring clients to their dependencies. If you forget to provide a dependency, Guice fails at startup. Guice handle…