Importing Packages

• Java classes are grouped into packages
• Import library classes by specifying the package and class name:
  import java.awt.Rectangle;
//Abstract Windowing Toolkit, for drawing windows & graphical shapes.
• You don't need to import classes in the java.lang package such as String and System

API: Application Programming Interface

• Lists classes and methods in the Java library
• https://docs.oracle.com/javase/8/docs/api/

Take a look of Rectangle class and String class. How does trim method work?