These are various small pieces of code that I created over the years for some purpose or other, mostly in Java. Some of them may be helpful to others, so I've put them here for wider access.
- ExprJava is a Java class that evaluates a mathematical expression by using a recursive-descent parser. It also handles variable substitution, and is useful for evaluating user-entered expressions.
- AntTask shows how to extend Ant with custom tasks
- WhoisLookup contains an implementation of a WHOIS lookup, based on the Apache Commons Net library (which has some limitations)
- SimpleMandel is a Java applet for displaying Mandelbrot sets of different exponents
- WebSockets shows how to use web sockets and server-sent events between a web page and a Java web app
Creating and altering PDF files
- PdfBox is an example of how to create a PDF file with the Apache PDFBox library, and how to use a few of its capabilities
- PdfboxAnnotation shows how to alter the appearance of text in a PDF (highlighting, underlining and striking out) using the PDFBox library
- PdfboxTable shows how to add tables to a PDF using the PDFBox and Boxable libraries
- PdfboxReplace shows how to search and replace text in a PDF in some circumstances using the PDFBox library
Some applets from way back when
, written by other people, resurrected here so they don't get lost.
- HexCalc is a simple calculator with binary, octal, decimal and hexdecimal modes
- Martin Minow's SunSphere applet shows a picture of the rotating earth, complete with sunlight and night shadow