//top\\ - Javfree

| Phase | Topics | Suggested Time | Mini‑Project | |-------|--------|----------------|--------------| | | • Installing JDK & IDE • Using javac & java • Basic console I/O ( System.out , Scanner ) | 1‑2 days | “Number Guessing Game” (loops + conditionals). | | 1️⃣ Core Language | • Primitive types, literals, operators • Control flow ( if , switch , for , while , do‑while ) • Methods (parameters, return values, overloading) • Arrays & var‑args • Basic exception handling ( try/catch/finally ) | 1‑2 weeks | “Simple Text File Analyzer” (read a file, count words/lines). | | 2️⃣ Object‑Oriented Java | • Classes & objects • Encapsulation (private fields, getters/setters) • Inheritance & super • Polymorphism (method overriding, interfaces) • final , abstract , static • enum and record (Java 21) | 2‑3 weeks | “Library Management System” (books, members, borrow/return). | | 3️⃣ Collections & Generics | • List , Set , Map (ArrayList, HashSet, HashMap) • Collections utility methods • Generics syntax & bounded types • Streams API (filter, map, reduce) | 1‑2 weeks | “CSV to JSON Converter” using streams. | | 4️⃣ I/O & Files | • java.io (File, InputStream, OutputStream) • java.nio.file (Path, Files) • Character encoding • Working with JSON (Jackson / Gson – both free) | 1 week | “Todo‑list CLI” persisted to a JSON file. | | 5️⃣ Concurrency | • Threads ( Thread , Runnable ) • Executor framework ( ExecutorService ) • Synchronization ( synchronized , Lock ) • CompletableFuture (async pipelines) | 1‑2 weeks | “Parallel URL Ping” – check many URLs concurrently. | | 6️⃣ Testing | • JUnit 5 (unit tests) • Mockito (mocking) • Test‑driven development (TDD) workflow | 1 week | Write unit tests for previous projects. | | 7️⃣ Build & Dependency Management | • Maven pom.xml basics • Gradle build.gradle.kts basics • Managing external libraries (Jackson, Log4j, SLF4J) | 3‑5 days | Convert a project to Maven/Gradle and publish to GitHub. | | 8️⃣ Web & Microservices (Optional) | • Servlets & JSP (Jakarta EE) • Spring Boot (REST API, dependency injection) • Reactive (Project Reactor) • Dockerizing a Java app | 3‑4 weeks | “RESTful Bookstore API” with Spring Boot + Docker. | | 9️⃣ Advanced Topics (Pick as needed) | • Java Modules ( module-info.java ) • Native interop (Project Panama) • GraalVM native images • Performance profiling (JFR, VisualVM) | Ongoing | Experiment with a small GraalVM native image. |

You should see:

Below is a ready‑to‑run project you can build in . It combines most core concepts and results in a useful CLI tool. javfree

Whether you're looking to start a new career or simply want to expand your skillset, JavFree is an excellent place to start. Join the JavFree community today and start exploring the world of Java! | Phase | Topics | Suggested Time |