model.setTreeName( "test" );
final TypeNode type = new TypeNodeImpl( "Person" );
final ConstraintNode c1 = new ConstraintNodeImpl( "doubleField",
"==",
new DoubleValue( 1000.56 ) );
model.setRoot( type );
type.getChildren().add( c1 );
final String drl = GuidedDecisionTreeDRLPersistence.getInstance().marshal( model );
assertEqualsIgnoreWhitespace( expected,