drools-retediagram

An experiment to plot Rete diagram, similar to ReteDumper, using Dot language format.

Usage

To plot the diagram files for a Knowledge Base of a given KieSession using the defaults:

java

ReteDiagram.newInstance().diagramRete(kieSession);

It is possible to change some settings and formatting, as in the following example:

java

ReteDiagram.newInstance()
    .configLayout(Layout.PARTITION) // use Partition layout, instead of default Vertical layout
    .configFilenameScheme(new File("./target"), true) // set output directory manually instead of OS default for temporary directory
    .configOpenFile(true, false) // automatically open SVG file with OS default application
    .diagramRete(kieSession);

Please notice to leverage the OS capability to automatically open file with the default application, it is required that the JVM property java.awt.headless but be false, which can be set manually with:

java

System.setProperty("java.awt.headless", "false");

Example: simple KB plotted with default Vertical layout

Given the following rules in the Knowledge Base:

rule "For color"
no-loop
when
  Measurement( id == "color", $colorVal : val )
then
  controlSet.add($colorVal);
end

rule "Likes cheddar"
when
  Cheese( $cheddar : name == "cheddar" )
  $person : Person( favouriteCheese == $cheddar )
then
  System.out.println( $person.getName() + " likes cheddar" );
end

rule "Don't like cheddar"
when
  Cheese( $cheddar : name == "cheddar" )
  $person : Person( favouriteCheese != $cheddar )
then
  System.out.println( $person.getName() + " does not like cheddar" );
end

rule "Color count"
when
  accumulate( $m: Measurement( id == "color" ); $c: count($m) )
then
  System.out.println( $c );
end

rule "Not a Color"
when
  not ( Measurement( id == "color" ) and String() )
then
  System.out.println( "no color yet." );
end

The diagram plotted with the defaults settings and Vertical layout:

java

ReteDiagram.newInstance().diagramRete(kieSession);

is rendered as:

the diagram displays the default entry point, Object Type nodes, Alpha nodes, Left Input Adapter nodes, join Beta nodes, etc. down to Rule Terminal nodes.

Example: plotting Partition layout

Given the following rules in the Knowledge Base:

rule R0 when
  $i : Integer( intValue == 0 )
  String( toString == $i.toString )
then
  list.add($i);
end
rule R1 when
  $i : Integer( intValue == 1 )
  String( toString == $i.toString )
then
  list.add($i);
end
rule R2 when
  $i : Integer( intValue == 2 )
  String( toString == $i.toString )
then
  list.add($i);
end
rule R3 when
  $i : Integer( intValue == 2 )
  String( length == $i )
then
  list.add($i);
end

The diagram plotted with the Partition layout:

java

ReteDiagram.newInstance().configLayout(Layout.PARTITION).diagramRete(ksession);

is rendered as:

The diagram displays nodes in their respective Partitions.