source: trunk/src/org/expeditee/simple/ExpediteeJEP.java@ 161

package org.expeditee.simple;

import java.text.NumberFormat;
import java.util.Observable;
import java.util.Observer;

import org.expeditee.gui.AttributeUtils;
import org.expeditee.gui.AttributeValuePair;
import org.expeditee.gui.Frame;
import org.expeditee.items.Text;
import org.nfunk.jep.JEP;
import org.nfunk.jep.Variable;

public class ExpediteeJEP extends JEP {
        Observer observer = new Observer() {
                private String _attribute = "";

                public void update(Observable ob, Object o) {
                        _attribute = ((Variable) o).getName() + ": ";
                }

                @Override
                public String toString() {
                        return _attribute;
                }
        };
        
        public ExpediteeJEP() {
                super();
                addStandardFunctions();
                addStandardConstants();
                setImplicitMul(true);
                setAllowAssignment(true);
                setAllowUndeclared(true);
        }
        
        public void addObserver() {
                getSymbolTable().addObserver(observer);
                getSymbolTable().addObserverToExistingVariables(observer);
        }

        public String getResult() {
                Double result = getValue();
                if(result.isNaN()){
                        return null;
                }               
                NumberFormat nf = NumberFormat.getInstance();
                nf.setMinimumFractionDigits(0);
                nf.setMaximumFractionDigits(15);
                return observer.toString() + nf.format(result);
        }

        public void addVariables(Frame frame) {
                if(frame == null)
                        return;
                // Check for variables
                for (Text t : frame.getTextItems()) {
                        AttributeValuePair avp = AttributeUtils.getPair(t.getText());
                        if (avp != null) {
                                addVariable(avp.getAttribute(), avp
                                                .getDoubleValue());
                        }
                }
        }
}