Application: gvSIG desktop

package org.gvsig.expressionevaluator.impl.function.date;

import java.util.Objects;

import org.apache.commons.lang3.Range;

import org.gvsig.expressionevaluator.Interpreter;

import org.gvsig.expressionevaluator.spi.AbstractFunction;

import org.gvsig.timesupport.DataTypes;

import org.gvsig.timesupport.RelativeInstant;

import org.gvsig.timesupport.RelativeInterval;

import org.gvsig.timesupport.TimeSupportLocator;

import org.gvsig.tools.ToolsLocator;

import org.gvsig.tools.dataTypes.Coercion;

import org.gvsig.tools.dataTypes.CoercionException;

public class RelativeIntervalFunction extends AbstractFunction {

    private final Coercion toInstant;

    public RelativeIntervalFunction() {

        super("Date", "RelativeInterval",Range.is(2),

            "Returns a relative interval from the arguments",

            "RelativeInterval({{date1}}, data2)",

            new String[]{

                "date1 - An object that represents a moment of time.",

                "date2 - An object that represents a moment of time."

            },

            "RelativeInterval",

            false

        );

        this.toInstant = ToolsLocator.getDataTypesManager().getCoercion(DataTypes.INSTANT);

    }

    @Override

    public boolean allowConstantFolding() {

        return true;

    }

    @Override

    public Object call(Interpreter interpreter, Object[] args) {

            Object arg0 = getObject(args, 0);

            Object arg1 = getObject(args, 1);

            try {

                RelativeInstant instant0 = (RelativeInstant) this.toInstant.coerce(arg0);

                RelativeInstant instant1 = (RelativeInstant) this.toInstant.coerce(arg1);

                RelativeInterval interval = TimeSupportLocator.getManager().createRelativeInterval(

                    instant0,

                    instant1

                );

                return interval;

            } catch (CoercionException ex) {

                throw new RuntimeException("Can't create an interval from '"+Objects.toString(arg0, "")+":"+Objects.toString(arg1, "")+"'.", ex);

            }

        }        

    }