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Author: rzhao271

README.md

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+# Magic Cube 3D
+
+This repository is a reupload of David Vanderschel's Magic Cube 3D (MC3D)
+program with a fix to get it working on more recent versions of Java.
+
+The original source code is available on the 
+[archived project page](https://web.archive.org/web/20180725112611/http://david-v.home.texas.net/MC3D/),
+and it's also available by viewing the initial commit for this repository.
+
+## Fixes and enhancements
+
+* Fixed a null pointer exception that shows up when running the compiled
+  program with Java 11 or newer.
+* Fixed some -Xlint:deprecation and -Xlint:unchecked warnings that appear
+  when compiling with Java 11 or newer.
+* Added a Makefile so that one can compile and package the project from the
+  command line.
+
+## Notes
+
+I learned it's best to compile this code with an older version of Java,
+but to verify with a newer version of Java:
+
+* Newer versions of Java can run code compiled by older versions of Java,
+  but not vice versa. 
+* Newer versions of Java might run the older Java code differently than
+  older versions of Java. In this case, the program was originally written for
+  Java 4, and a new bug appeared when running the program using Java 11.
+  At the time of this upload, users are likely on at least Java 11,
+  which explains why the original jar file didn't seem to work anymore.
+
+## License
+
+The code is licensed under the GPLv2 with David Vanderschel as the author.
+The copyright statements date back to 2005-2006.