Which Package is automatically imported in any Java Program?

The java.lang package is automatically imported in any Java Program. java.lang package need not be explicitly imported. The classes of java.lang package can be accessed directly.

The java.lang package includes classes, interfaces and enumerated types that are closely related to language and the run time system. Few prominent classes of java.lang package are: java.lang.Object, java.lang.Class, java.lang.String, java.lang.StringBuffer, java.lang.StringBuilder, java.lang.Math, java.lang.Error, java.lang.Exception and java.lang.RuntimeException.

Note that java.lang is the one and only package that is automatically imported in any java program.