🔸 TLDR
JSF/Jakarta Faces is a component-based, server-side UI framework for Java web apps, powered by Facelets (XHTML templates) + managed beans + a strong lifecycle for forms/validation.
🔸 WHAT IS JSF (JAKARTA FACES)?
JSF (today called Jakarta Faces) is a server-side Java web framework for building UIs using component-based views, EL (Expression Language), and a managed bean model.
▪️ You write views in XHTML
▪️ JSF builds a component tree, runs a request lifecycle (convert/validate/update/invoke/render)
▪️ Great fit for form-heavy, enterprise web apps with strong validation + state handling ✅
🔸 WHAT ARE FACELETS?
Facelets is JSF’s view technology (the “templating + page” layer).
▪️ Views are .xhtml files (not JSP)
▪️ You get templating (ui:composition, ui:define)
▪️ You use JSF component tags (h:*) + EL bindings (#{bean.value})
▪️ Easy to compose pages with reusable layouts and fragments 🧱
🔸 MINI JSF APP SNIPPET
Here’s a tiny “Hello JSF” with a form + backing bean.
▪️ index.xhtml
▪️ HelloBean.java
🔸 TAKEAWAYS
▪️ JSF shines for enterprise CRUD + complex forms ✅
▪️ Facelets makes templating and reuse straightforward 🧱
▪️ The JSF lifecycle is a superpower… and the main thing to learn 🧠
▪️ If you want richer components, ecosystems like PrimeFaces can level it up ⚡
#Java #JakartaEE #JSF #JakartaFaces #Facelets #EnterpriseJava #JavaWeb #CDI #PrimeFaces #WebDevelopment