equals()とhashCode()をオーバーライドしないと何が起きるか
https://qiita.com/S_kamon/items/e80c066455beca2e344e?utm_campaign=popular_items&utm_medium=feed&utm_source=popular_items

#qiita #Java #hashcode #equals

Wer in Java eigene Klassen schreibt, kommt früher oder später an den Punkt, an dem `equals()`, `hashCode()` und `toString()` relevant werden. Diese drei Methoden stammen alle aus der Klasse `Object`, also der obersten Basisklasse in Java. Deshalb hat jede Klasse sie automatisch - aber oft reicht d

https://magicmarcy.de/equals-hashcode-und-tostring-richtig-implementieren

#equals #hashCode #toString #Basisklasse #Grundlagen #Object #vergleichen #Collections #Hash-basiert

🤦‍♂️ Why String.GetHashCode in .NET Drives You Crazy 🤪

➡ I needed to keep track of transactions between tool runs. I saved a hashcode of a transaction in DB.

➡ Tool would generate a new hash-code and compare it to the one already saved in DB.

➡ At same run, it is fine. But, after re-running, generated hashcode -of the same transaction- is not same as one in DB.

➡ Read this article to know how to overcome this.

📖 https://developmentsimplyput.com/post/when-string-gethashcode-in-net-c-drives-you-crazy

📭 http://developmentsimplyput.com/subscribe

#dotnet #softwaredesign #softwarearchitecture #bestpractice #string #hashcode

🤦‍♂️ Why String.GetHashCode in .NET Drives You Crazy 🤪

➡ I needed to keep track of transactions between tool runs. I saved a hashcode of a transaction in DB.

➡ Tool would generate a new hash-code and compare it to the one already saved in DB.

➡ At same run, it is fine. But, after re-running, generated hashcode -of the same transaction- is not same as one in DB.

➡ Read this article to know how to overcome this.

📖 https://developmentsimplyput.com/post/when-string-gethashcode-in-net-c-drives-you-crazy

📭 http://developmentsimplyput.com/subscribe

#dotnet #string #hashcode