Java Interview Guide : 200+ Interview Questions and Answers - Java Classloaders

The video tutorial explains the role of class loaders in Java, which are responsible for loading classes needed by a Java program. It describes three types of classes: those written by programmers, those provided by frameworks, and system classes. The tutorial details three types of class loaders: system, extension, and bootstrap, each with specific search paths. The system class loader searches the classpath, the extension class loader searches the extension directory, and the bootstrap class loader loads core Java files. The order of class loader execution is system, extension, and bootstrap. If a class is not found, a 'class not found' exception is thrown.

What are the three main types of classes in Java programs?

• Primitive, reference, and wrapper classes

• User-defined, framework, and system classes

• Public, private, and protected classes

• Static, dynamic, and abstract classes

Which class loader is responsible for loading classes from the classpath?

• Extension class loader

• Bootstrap class loader

• System class loader

• Custom class loader

Where does the extension class loader search for classes?

• In the user-defined directories

• In the core Java files

• In the extension directory

• In the classpath

What is the first class loader that the JRE consults when searching for a class?

• Extension class loader

• Custom class loader

• Bootstrap class loader

• System class loader

What happens if a class is not found by any of the class loaders?

• The class is automatically created

• A class not found exception is thrown

• A default class is used

• The program continues without the class