This is a comprehensive guide and summary structured around the famous "Core Java" notes by Durga Sir (Durga Software Solutions). His notes are widely considered the gold standard for Java beginners and students preparing for interviews and certifications.
He famously drills into the student: “Without JVM, no Java execution. But JVM is platform dependent, while Java is platform independent.” This paradox is the gateway to understanding architecture.
Thread class vs. Implementing Runnable interface.Runnable is preferred because Java doesn’t support multiple inheritance for classes.Common Interview Questions & Practical Problems
wait(), notify(), notifyAll(). The notes explicitly state: These must be called from a synchronized context (inside synchronized block), otherwise IllegalMonitorStateException.