How do you define constants in Java?

In Java, you can use the final keyword to define constants, which cannot be modified.

Constants can be defined at the class level (static constants) or at the instance level (instance constants).

When defining constants at the class level, the modifiers for constants should be public static final, for example:

public class MyClass {
    public static final int MAX_VALUE = 100;
}

Constants defined in this way can be accessed using the class name, for example MyClass.MAX_VALUE.

When defining constants at the instance level, the modifier for the constant should be public static final, and it cannot include the static keyword. For example:

public class MyClass {
    public final int MAX_VALUE = 100;
}

Constants defined this way can be accessed by the instance name, for example MyClass instance = new MyClass(); instance.MAX_VALUE.

Regardless of whether it is at the class level or instance level, it is important to adhere to naming conventions for constants. Constants are usually named using capital letters and underscores, such as MAX_VALUE.