Top Java interview questions and answers
1. What is the difference between JDK, JRE, and JVM? Answer : JDK (Java Development Kit) : It’s a software development kit used to develop Java applications, which includes tools like the compiler ( javac ), JavaDoc, and Java Debugger. It also includes JRE. JRE (Java Runtime Environment) : Provides libraries, Java Virtual Machine (JVM), and other components to run Java applications. It’s used by end-users who want to run Java programs. JVM (Java Virtual Machine) : The heart of Java, it allows Java applications to run on any device or OS. It converts bytecode into machine code. 2. What is the difference between == and equals() in Java? Answer : == is used to compare primitive types and checks for reference equality with objects, meaning it checks if two references point to the same object in memory. equals() is a method from the Object class and is used to compare the contents of two objects. For example, String class overrides equals() to check if two strings have the same...