21.02.25 TIL

- SQL

solved 1 problem✔

 

- Woowa Course

 

[Techtalk]

 

DTO : Data Transfer Object between View layer and Service Layer. Setter is not suggested to be immutable.

VO : must be immutable. Overriding on equals, hashcode is necessary. Therefore, it means equal if inner values are same. Setter is denied.

 

MVC, this concept were also very useful. It was surprised that everyone explains very well.

 

[Code Review]

 

I refactored code for a while. It was difficult to be more cohensive but be lower coupling. I tried to make Money class to be more useful. I am not sure that doing right. I am waiting for review about it. 👀

 

Below is studyLog about ArrayList. It makes more effective if the size is initialized.

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학습로그 2-3

[Java] ArrayList - 2

내용

• ArrayList는 초기크기는 10이고, 추가되는 값에 따라 크기를 늘려준다. 초기화 당시 크기를 지정해주면 소소한 성능향상이 가능하다.
• addAll을 사용하면 기존 리스트 내역을 추가가능하다.

링크

ArrayList javadocs

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- Algorithm

I failed to solve the today's problem but I think I could solve it after study session. 

I need to study Segment Tree. It is useful algorithm concept when calculating sum of specific section. 👀

 

 

- MeetCoder Posting

I wrote about Cookie and Session but it is needed to be improved. Do it tomorrow! ✔