basemannerstest.java

jboss规则引擎

    /**
     * <pre>
     * rule continue() { 
     *     Context context; 
     *     when { 
     *         context : Context( state == Context.CHECK_DONE ) 
     *     } then { 
     *         context.setState( Context.ASSIGN_SEATS ); 
     *     } 
     * }
     * </pre>
     * @return
     * @throws IntrospectionException
     * @throws InvalidRuleException
     */
    private Rule getContinueProcessing() throws IntrospectionException,
                                        InvalidRuleException {
        final Rule rule = new Rule( "continueProcessng" );

        // -----------
        // context : Context( state == Context.CHECK_DONE )
        // -----------
        final Column contextColumn = new Column( 0,
                                                 this.contextType,
                                                 "context" );

        contextColumn.addConstraint( getLiteralConstraint( contextColumn,
                                                           "state",
                                                           new Integer( Context.CHECK_DONE ),
                                                           this.integerEqualEvaluator ) );

        rule.addPattern( contextColumn );
        final Declaration contextDeclaration = rule.getDeclaration( "context" );

        // ------------
        // context.setName( Context.ASSIGN_SEATS );
        // ------------
        final Consequence consequence = new Consequence() {

            public void evaluate(KnowledgeHelper drools,
                                 WorkingMemory workingMemory) throws ConsequenceException {
                try {
                    Rule rule = drools.getRule();
                    Tuple tuple = drools.getTuple();

                    Context context = (Context) drools.get( contextDeclaration );
                    context.setState( Context.ASSIGN_SEATS );

                    drools.modifyObject( tuple.get( contextDeclaration ),
                                         context );

                    //System.out.println( "continue processing" );
                } catch ( Exception e ) {
                    e.printStackTrace();
                    throw new ConsequenceException( e );
                }
            }

        };

        rule.setConsequence( consequence );

        return rule;
    }

    /**
     * <pre>
     * rule all_done() { 
     *     Context context; 
     *     when { 
     *         context : Context( state == Context.PRINT_RESULTS ) 
     *     } then {
     *     } 
     * }
     * </pre>
     * 
     * @return
     * @throws IntrospectionException
     * @throws InvalidRuleException
     */
    private Rule getAllDone() throws IntrospectionException,
                             InvalidRuleException {
        final Rule rule = new Rule( "alldone" );

        // -----------
        // context : Context( state == Context.PRINT_RESULTS )
        // -----------
        final Column contextColumn = new Column( 0,
                                                 this.contextType );

        contextColumn.addConstraint( getLiteralConstraint( contextColumn,
                                                           "state",
                                                           new Integer( Context.PRINT_RESULTS ),
                                                           this.integerEqualEvaluator ) );

        rule.addPattern( contextColumn );
        final Declaration contextDeclaration = rule.getDeclaration( "context" );

        // ------------
        //     
        // ------------
        final Consequence consequence = new Consequence() {

            public void evaluate(KnowledgeHelper drools,
                                 WorkingMemory workingMemory) throws ConsequenceException {
                try {
                    System.err.println( "all done" );
                } catch ( Exception e ) {
                    throw new ConsequenceException( e );
                }
            }

        };

        rule.setConsequence( consequence );

        return rule;
    }

    /**
     * Convert the facts from the <code>InputStream</code> to a list of
     * objects.
     */
    protected List getInputObjects(final InputStream inputStream) throws IOException {
        final List list = new ArrayList();

        final BufferedReader br = new BufferedReader( new InputStreamReader( inputStream ) );

        String line;
        while ( (line = br.readLine()) != null ) {
            if ( line.trim().length() == 0 || line.trim().startsWith( ";" ) ) {
                continue;
            }
            final StringTokenizer st = new StringTokenizer( line,
                                                            "() " );
            final String type = st.nextToken();

            if ( "guest".equals( type ) ) {
                if ( !"name".equals( st.nextToken() ) ) {
                    throw new IOException( "expected 'name' in: " + line );
                }
                final String name = st.nextToken();
                if ( !"sex".equals( st.nextToken() ) ) {
                    throw new IOException( "expected 'sex' in: " + line );
                }
                final String sex = st.nextToken();
                if ( !"hobby".equals( st.nextToken() ) ) {
                    throw new IOException( "expected 'hobby' in: " + line );
                }
                final String hobby = st.nextToken();

                final Guest guest = new Guest( name,
                                               Sex.resolve( sex ),
                                               Hobby.resolve( hobby ) );

                list.add( guest );
            }

            if ( "last_seat".equals( type ) ) {
                if ( !"seat".equals( st.nextToken() ) ) {
                    throw new IOException( "expected 'seat' in: " + line );
                }
                list.add( new LastSeat( new Integer( st.nextToken() ).intValue() ) );
            }

            if ( "context".equals( type ) ) {
                if ( !"state".equals( st.nextToken() ) ) {
                    throw new IOException( "expected 'state' in: " + line );
                }
                list.add( new Context( st.nextToken() ) );
            }
        }
        inputStream.close();

        return list;
    }

    private InputStream generateData() {
        final String LINE_SEPARATOR = System.getProperty( "line.separator" );

        final StringWriter writer = new StringWriter();

        final int maxMale = this.numGuests / 2;
        final int maxFemale = this.numGuests / 2;

        int maleCount = 0;
        int femaleCount = 0;

        // init hobbies
        final List hobbyList = new ArrayList();
        for ( int i = 1; i <= this.maxHobbies; i++ ) {
            hobbyList.add( "h" + i );
        }

        final Random rnd = new Random();
        for ( int i = 1; i <= this.numGuests; i++ ) {
            char sex = rnd.nextBoolean() ? 'm' : 'f';
            if ( sex == 'm' && maleCount == maxMale ) {
                sex = 'f';
            }
            if ( sex == 'f' && femaleCount == maxFemale ) {
                sex = 'm';
            }
            if ( sex == 'm' ) {
                maleCount++;
            }
            if ( sex == 'f' ) {
                femaleCount++;
            }

            final List guestHobbies = new ArrayList( hobbyList );

            final int numHobbies = this.minHobbies + rnd.nextInt( this.maxHobbies - this.minHobbies + 1 );
            for ( int j = 0; j < numHobbies; j++ ) {
                final int hobbyIndex = rnd.nextInt( guestHobbies.size() );
                final String hobby = (String) guestHobbies.get( hobbyIndex );
                writer.write( "(guest (name n" + i + ") (sex " + sex + ") (hobby " + hobby + "))" + LINE_SEPARATOR );
                guestHobbies.remove( hobbyIndex );
            }
        }
        writer.write( "(last_seat (seat " + this.numSeats + "))" + LINE_SEPARATOR );

        writer.write( LINE_SEPARATOR );
        writer.write( "(context (state start))" + LINE_SEPARATOR );

        return new ByteArrayInputStream( writer.getBuffer().toString().getBytes() );
    }

    public static int getIndex(final Class clazz,
                               final String name) throws IntrospectionException {
        final PropertyDescriptor[] descriptors = Introspector.getBeanInfo( clazz ).getPropertyDescriptors();
        for ( int i = 0; i < descriptors.length; i++ ) {
            if ( descriptors[i].getName().equals( name ) ) {
                return i;
            }
        }
        return -1;
    }

    private FieldConstraint getLiteralConstraint(final Column column,
                                                 final String fieldName,
                                                 final Object fieldValue,
                                                 final Evaluator evaluator) throws IntrospectionException {
        final Class clazz = ((ClassObjectType) column.getObjectType()).getClassType();

        final FieldExtractor extractor = new ClassFieldExtractor( clazz,
                                                                  fieldName );

        final FieldValue field = new MockField( fieldValue );

        return new LiteralConstraint( field,
                                      extractor,
                                      evaluator );
    }

    private void setFieldDeclaration(final Column column,
                                     final String fieldName,
                                     final String identifier) throws IntrospectionException {
        final Class clazz = ((ClassObjectType) column.getObjectType()).getClassType();

        final FieldExtractor extractor = new ClassFieldExtractor( clazz,
                                                                  fieldName );

        column.addDeclaration( identifier,
                               extractor );
    }

    private FieldConstraint getBoundVariableConstraint(final Column column,
                                                       final String fieldName,
                                                       final Declaration declaration,
                                                       final Evaluator evaluator) throws IntrospectionException {
        final Class clazz = ((ClassObjectType) column.getObjectType()).getClassType();

        final FieldExtractor extractor = new ClassFieldExtractor( clazz,
                                                                  fieldName );

        return new BoundVariableConstraint( extractor,
                                            declaration,
                                            evaluator );
    }
}