OCJP Certification Guide

What OCJP is OCJP – the Oracle Certified Professional: Java SE Programmer certification – validates that you can write correct, idiomatic Java. It's a well-recognised ...

Primitives and literals Java has eight primitives: byte, short, int, long, float, double, char, boolean . Know their sizes and default values, and watch literal forms: Wrappers ...

The four pillars OOP is the heart of the exam. Master the four pillars: Overriding vs overloading Overriding – a subclass redefines a superclass method with the same ...

The Collections Framework List ( ArrayList ) – ordered, allows duplicates, indexed. Set ( HashSet ) – no duplicates, no order guarantee. Map ( HashMap ) – key ...

Exceptions Know the hierarchy and the rules: Checked exceptions ( IOException ) must be caught or declared. Unchecked exceptions ( RuntimeException and subclasses like ...

A study plan that works Learn a topic, then write code that exercises its edge cases. Keep a notes file of rules you keep forgetting (autoboxing, overload resolution). Take ...