Chapter 21: Stream API (Java 8+)
The Stream API lets you process collections (lists, sets, arrays, etc.) in a declarative style — you tell what you want to do, not how to do it step-by-step. It’s like giving instructions to...
Category: Java
Chapter 22: File I/O and Serialization
Almost every real-world Java application needs to read data from files (configuration, logs, user data, CSV, JSON…) write data to files (save game progress, generate reports, export data…) serialize objects (save them to disk,...
Chapter 23: Date & Time API (Java 8+)
Before Java 8, working with dates and times was painful: java.util.Date was mutable, confusing, and full of bugs java.util.Calendar was complex and error-prone Mixing them was a nightmare In 2014, Java 8 gave us...
Chapter 24: JDBC (Database Connectivity)
JDBC is the official Java API for connecting to relational databases. It’s been around since Java 1.1 (1997) and is still the foundation of almost every Java backend application in 2026 (Spring Boot, Hibernate,...
25. Advanced Topics (Optional for Intermediate Level)
This chapter is marked as optional for intermediate level, but trust me — these topics are extremely important in real-world Java development (especially in 2026). Many companies ask about them in interviews, and they...
