Xah Java Tutorial: About The Author

By Xah Lee. Date:

Xah Lee (me) have been programing in Java since 2001. I'm a expert in Mathematica, Perl, Python, Emacs Lisp.

I worked as a full-time unix sys admin and web application developer during 1998 – 2002 using Solaris, MySQL, Apache, JServ (Java Tomcat servlet precedent), and using Perl and Java to write inhouse application servers.

I started to use a computer in 1990, using the QWERTY keyboard. In ~1992 i worked for over a year as a secretary with typing duties. I switched to the Dvorak layout in about 1993. My first job in programing is 1995 at Wolfram Research, programing Mathematica.

If you have a question, put $5 at patreon and message me.


  1. Install
  2. javac java jar javadoc

Java Basics

  1. Print String
  2. Strings
  3. Power Function
  4. Java Types and Type Conversion
  5. Function
  6. Arrays

Class, Inheritance

  1. extends
  2. Constructor
  3. Constructor Return Type
  4. Extending a Class that has Explicit Constructors
  5. static
  6. this
  7. super
  8. Access Specifiers

Abstract class, Interface

  1. abstract
  2. Interface


  1. Package


  1. Collection, Map
  2. Read/Write File
  3. Convert File Encoding
  4. Complex Numbers in Java
  5. Unicode
  6. Number Literals