Automatizer is an Eclipse plugin for manipulating finite-state automata and regular expressions. It can help beginners to understand relationships between FSA and regexps.

1. Go to Help > Install New Software... in your Eclipse IDE
2. Add http://chaoslawful.github.io/automatizer/update/ in update sites
3. Check Automatizer group in available plugins list, click Next button and follow the installation instructions.
4. Restart Eclipse

Press Ctrl-Alt-Z to show automatizer view and select any text. The plugin will then parse the selection as regular expression and show corresponding FSA transition diagram in the view.

If the selected text is in Graphviz DOT syntax, the plugin will try to parse it as description of a FSA and show the corresponding transition diagram. For successfully parsing, the DOT text must comply with the following restrictions:

1. Initial state must be pointed to by a node named initial
2. Final states must have the attribute shape=doublecircle
3. The attribute label on the edges is the transition condition, which must be a single character, a character range (like a-z) or a character set (like [xyz])

For example:

digraph G {
	2 [shape=doublecircle];
	initial -> 1;
	1 -> 2 [label="a-z"];
	1 -> 2 [label="[234]"];
	1 -> 2 [label="@"];
	2 -> 1 [label="[01]"];
}

If you clicked Show Regexp in context menu of the view, the regular expression string converted from the current automaton would also be shown along with the transition diagram.

This plugin provides the following features:

• Show ε-free NFA or minimized DFA corresponding to a regular expression
• Show streaming matching variants of the automata
• Show regular expression corresponding to current automaton using state elimination method
• Export automata transition diagram to image or Graphviz DOT file

• Integrate some kind of regexp minimization algorithm
• Integrate some kind of NFA minimization algorithm
• Add ability to show ε-NFA transition diagram
• Improve transition diagram layout (has to wait for release of Zest 2.x)

• Wang, Xiaozhe (@chaoslawful)

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