Which base class is the superclass for Integer, Long, and Double types in Java?

In Java, the superclass for wrapper types Integer, Long, and Double is the class Number. This abstract class provides methods for obtaining the value in various numeric formats, such as intValue(), longValue(), doubleValue(), and others.

Example:

Integer i = 10;
Long l = 100L;
Double d = 3.14;

Number n = i; // Integer inherits from Number
System.out.println(n.doubleValue()); // Will output 10.0