Application: gvSIG desktop

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

import java.io.File;

import java.net.URI;

import java.net.URL;

import org.apache.commons.lang3.Range;

import org.gvsig.expressionevaluator.ExpressionRuntimeException;

import org.gvsig.expressionevaluator.Function;

import org.gvsig.expressionevaluator.Interpreter;

import org.gvsig.expressionevaluator.spi.AbstractFunction;

public class FileFunction extends AbstractFunction {

    public static final String NAME = "FILE";

    public FileFunction() {

        super(Function.GROUP_PROGRAMMING, 

            NAME, 

            Range.is(1),

            null,

            NAME+"({{expression}})",

            null,

            "Object",

            false

        );

    }

    @Override

    public boolean allowConstantFolding() {

        return false;

    }

    @Override

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

        Object obj = getObject(args, 0);

        File value = toFile(obj);

        return value;

    }

    public static File toFile(Object obj) {

        if( obj == null ) {

            return null;

        }        

        if( obj instanceof File ) {

            return (File) obj;

        } else if( obj instanceof CharSequence ) {

            return new File(((CharSequence)obj).toString());

        } else if( obj instanceof URI ) {

            return new File(((URI)obj));

        } else if( obj instanceof URL ) {

            return new File(((URL)obj).getPath());

        } else {

            throw new ExpressionRuntimeException("The "+NAME+" function require a File or a String and a received a '"+obj.getClass().getSimpleName()+"'.");

        }

    }

}