What Are The Object And Class Classes Used For

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The Object class is the highest-level class in the Java class hierarchy. The Class class is used to represent the classes and interfaces that are loaded by a Java program.

In Core Java, the Object and Class classes serve distinct purposes.

  1. Object Class:
    • The Object class is at the top of the Java class hierarchy.
    • Every class in Java is directly or indirectly derived from the Object class.
    • It provides several methods that are common to all objects, such as toString(), equals(), hashCode(), and getClass().
    • These methods can be overridden in user-defined classes to provide custom implementations.
  2. Class Class:
    • The Class class is part of the java.lang package.
    • It is used to represent classes and interfaces in a running Java application.
    • It provides methods to get information about a class or interface, such as its name, fields, methods, and constructors.
    • Class class is commonly used in reflection, a feature that allows you to inspect and interact with classes, methods, and fields dynamically at runtime.

Here’s a brief example:

java
// Using Object class
public class ExampleObjectClass {
public static void main(String[] args) {
Object obj = new Object();
System.out.println(obj.toString()); // toString() method from Object class
}
}// Using Class class
public class ExampleClassClass {
public static void main(String[] args) {
Class<?> clazz = String.class;
System.out.println(“Class Name: “ + clazz.getName());
System.out.println(“Simple Name: “ + clazz.getSimpleName());
}
}

In summary, the Object class provides a base for all classes and includes common methods, while the Class class is used for obtaining metadata about classes and interfaces at runtime.