Application: gvSIG desktop

package org.gvsig.labeling.operations;

import java.util.ArrayList;

import java.util.Hashtable;

import com.hardcode.gdbms.engine.values.Value;

import com.iver.cit.gvsig.fmap.Messages;

/**

 * Implements the funcionality of a division operator

 *

 * @author Pepe Vidal Salvador - jose.vidal.salvador@iver.es

 *

 */

public class DivOperator extends Operator {

        private ArrayList<Expression> arguments = new ArrayList<Expression>();

        public String getName() {

                return OperationTags.DIV_OP;

        }

        public DivOperator(Hashtable<String, Value> symbol_table) {

                super(symbol_table);

        }

        public Object evaluate()throws ExpressionException {

                Double doubleResult = null;

                Integer intResult = null;

                try {

                        intResult = (Integer)((Expression)arguments.get(0)).evaluate();

                        if (intResult==null)

                                return new Integer(0);

                        if (arguments.size() == 1)

                                return intResult;

                        for (int i = 1; i < arguments.size(); i++){

                                Expression function = (Expression)arguments.get(i);

                                Integer value2=((Integer)function.evaluate());

                                if (value2==null)

                                        value2=new Integer(1);

                                intResult /= value2;

                        }

                        return intResult;

                } catch (ClassCastException e) {

                        Object value1=((Expression)arguments.get(0)).evaluate();

                        if (value1==null)

                                return new Double(0);

                        doubleResult = new Double(value1.toString());

                        if(arguments.size() == 1)

                                return doubleResult;

                        for (int i = 1; i < arguments.size(); i++){

                                Expression function = (Expression)arguments.get(i);

                                Object value2=((Expression)function).evaluate();

                                if (value2==null){

                                        value2=new Double(1);

                                }

                                doubleResult /= new Double(((Expression)function).evaluate().toString());

                        }

                        return doubleResult;

                }

        }

        public void addArgument(int i, Expression arg) {

                arguments.add(i, arg);

        }

        public String getPattern() {

                return "("+Messages.getString(OperationTags.OPERAND)

                + OperationTags.DIV_OP +Messages.getString(OperationTags.OPERAND)+ ")\n"+

                Messages.getString(OperationTags.OPERAND) +" = "+

                Messages.getString(OperationTags.NUMERIC_VALUE);                }

        public ArrayList<Expression> getArguments() {

                return arguments;

        }

        public void setArguments(ArrayList<Expression> arguments) {

                this.arguments = arguments;

        }

        public void check() throws ExpressionException {

//                if (arguments.size() == 2 && arguments.get(1).evaluate(symbol_table).equals(0.0))

//                throw new ExpressionException(ExpressionException.DIVIDED_BY_CERO);

                for (int i = 0; i < arguments.size(); i++) {

                        if(!(arguments.get(i)instanceof NumericalConstant))

                                throw new ExpressionException(ExpressionException.CLASS_CASTING_EXCEPTION);

                        Double doubleResult = new Double(((Expression)arguments.get(i)).evaluate().toString());

                        if((Double.isInfinite(doubleResult))

                                || (Double.isNaN(doubleResult))

                                || (i!= 0 && doubleResult.equals(0.0)))

                                throw new ExpressionException(ExpressionException.DIVIDED_BY_CERO);

                }

        }

}