Series 21 · 9 Parts· 1h 44m

Java EE & Legacy Java Modernization

Modernizing a legacy Java estate slice by slice — old JDK to a modern LTS JVM, Java EE to Jakarta EE / Spring Boot, and EJB and app-server monoliths to domain services, parity proven.

Start reading · Part 1

Contents

01 Legacy Java Modernization: A Field Guide 11 min read What a legacy Java estate actually is — a frozen JDK, a dead framework namespace, a heavyweight app server, and a stale frontend, all entangled — and the incremental way off it without a big-bang rewrite.
02 Java 8 to Java 21: Modernizing the JVM 11 min read Why the runtime moves first — the JDK lifecycle and LTS cadence, what actually breaks between Java 8 and Java 21, and how to upgrade the JVM without halting delivery.
03 Java EE to Spring Boot & Jakarta EE 12 min read The framework move — what the javax to jakarta namespace break really means, how to choose between Jakarta EE and Spring Boot, and how to cross the line one slice at a time.
04 Migrating Off EJB and Struts 14 min read The hardest parts of a legacy Java framework to leave — what EJB's container guarantees actually provided, why Struts is a security liability as well as a dead end, and how to lift both out a slice at a time.
05 Java Monolith to Microservices 12 min read Getting off the heavyweight app server (WebLogic, WebSphere, JBoss) and decomposing a Java monolith to microservices, but only where a real scaling, autonomy, or isolation pressure justifies it.
06 AngularJS & Legacy Frontend Modernization 11 min read The layer in front of the Java backend — why an end-of-life AngularJS or JSP/Struts UI is its own risk, and how to modernize the frontend incrementally alongside the services it talks to.
07 Java Modernization with AI 11 min read Where AI genuinely changes legacy Java modernization — reading EJB and Struts code, capturing undocumented rules, accelerating translation — and where it must stay under human review and never replace the parity gate.
08 Java Modernization Tools Compared 11 min read A category map of Java modernization tooling — analyzers, automated refactoring, namespace migrators, and AI translators — what each genuinely does, where each stops, and why none of them is the deciding factor it's sold as.
09 What Java Modernization Costs 11 min read The business case for a Java modernization — where the cost actually sits across runtime, framework, and decomposition, why the incremental approach changes the spending shape, and how to weigh it against the cost of standing still.