[JAVA] I made a chat app.


I made a chat app as a practice of web app.

Basic function

--Login-based app --Password is hashed and managed in DB --Login management function using session --Account creation function --Message posting function --Save the posted content in the DB --XSS countermeasure escape processing --Image posting function --Convert images to byte array and save to reduce weight --Input check function --At login --When creating an account --When posting a message --Message deletion / editing function (From the user's point of view, individual messages saved in the DB can be deleted / edited individually) --App design using Bootstrap framework --Responsive design compatible with smartphones

Development environment

--Language - Java - javascript - html - css --Database - MySQL --Other - bootstrap


Login screen

--For PC roguinngamen.png --For smartphones -Smartphone screen.jpg

Chat screen

--For PC チャット画面.png

--For smartphones tyattogamen.png

Impressions made

――It's often troublesome to make an ordinary chat app. --Both processing for determining line breaks and XSS countermeasures --I learned that it is better to convert to a byte string when posting an image. When displaying, I chose the method of encoding to base64 and displaying it, but this method puts a load on displaying the page, so I would like to reflect on it in the future. ――I'm not confident in the design, so thanks to bootstrap, it's much better.


Even though it is a chat app, its processing and structure are almost the same as or similar to bulletin boards and apps with other input forms, so it turned out that other apps can also be used.

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