Application: gvSIG desktop

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

import org.apache.commons.lang3.Range;

import org.gvsig.expressionevaluator.ExpressionBuilder;

import org.gvsig.expressionevaluator.ExpressionEvaluatorLocator;

import org.gvsig.expressionevaluator.ExpressionEvaluatorManager;

import org.gvsig.expressionevaluator.Function;

import org.gvsig.expressionevaluator.Interpreter;

import org.gvsig.expressionevaluator.MutableSymbolTable;

import org.gvsig.expressionevaluator.SymbolTable;

import org.gvsig.expressionevaluator.spi.AbstractFunction;

import org.gvsig.tools.script.Script;

public class ImportFunction extends AbstractFunction {

    public static final String FUNCTION_IMPORT = "IMPORT";

    public ImportFunction() {

        super(Function.GROUP_PROGRAMMING, 

            FUNCTION_IMPORT, 

            Range.is(1),

            "Import a module from the current resources storage",

            FUNCTION_IMPORT+" {{module}}",

            new String[]{

                "module - Module name to import"

            },

            "Script",

            false

        );

    }

    @Override

    public boolean allowConstantFolding() {

        return false;

    }

    @Override

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

        String name = getStr(args,0);

        if( name == null ) {

            throw new NullPointerException("A string with a module name was expected and a null was received");

        }

        SymbolTable symbolTable = interpreter.getSymbolTable();

        if( symbolTable instanceof MutableSymbolTable ) {

            ExpressionEvaluatorManager expressionManager = ExpressionEvaluatorLocator.getExpressionEvaluatorManager();

            Script module = expressionManager.loadScript(interpreter.getResourcesStorage(), name);

            if( module == null ) {

                return null;

            }

            ((MutableSymbolTable)symbolTable).setVar(name, module);

            return module;

        } 

        return null;

    }

}