Application: gvSIG desktop

package org.gvsig.expressionevaluator.impl.javascripting;

import java.io.IOException;

import java.io.Reader;

import java.io.Writer;

import java.util.List;

import javax.script.AbstractScriptEngine;

import javax.script.Bindings;

import javax.script.Compilable;

import javax.script.CompiledScript;

import javax.script.Invocable;

import javax.script.ScriptContext;

import javax.script.ScriptEngine;

import javax.script.ScriptEngineFactory;

import javax.script.ScriptException;

import javax.script.SimpleScriptContext;

import org.apache.commons.io.IOUtils;

import org.apache.commons.lang3.StringUtils;

import org.gvsig.expressionevaluator.Code;

import org.gvsig.expressionevaluator.ExpressionEvaluatorLocator;

import org.gvsig.expressionevaluator.ExpressionEvaluatorManager;

import org.gvsig.expressionevaluator.ExpressionRuntimeException;

import org.gvsig.expressionevaluator.Interpreter;

import org.gvsig.expressionevaluator.MutableSymbolTable;

/**

 *

 * @author jjdelcerro

 */

public class CosaScriptEngine 

        extends AbstractScriptEngine

        implements ScriptEngine, Compilable, Invocable

    {

    private class MyContextScript extends SimpleScriptContext {

        public MyContextScript() {

            engineScope = new SymbolTableToBindingsAdapter(symbolTable);

        }

        @Override

        public void setWriter(Writer writer) {

            super.setWriter(writer);

            interpreter.setWriter(writer);

        }

        @Override

        public void setErrorWriter(Writer writer) {

            super.setErrorWriter(writer); 

        }

    }

    private final ScriptEngineFactory factory;

    private final MutableSymbolTable symbolTable;

    private final Interpreter interpreter;

    private final ExpressionEvaluatorManager manager;

    public CosaScriptEngine(ScriptEngineFactory factory) {

        this.factory = factory;

        this.manager = ExpressionEvaluatorLocator.getManager();

        this.symbolTable = manager.createSymbolTable();

        this.interpreter = manager.createInterpreter();

        this.interpreter.setSymbolTable(this.symbolTable);

        this.context = new MyContextScript();        

    }

    @Override

    public ScriptEngineFactory getFactory() {

       return this.factory;

    }

    @Override

    public Object eval(String source, ScriptContext context) throws ScriptException {

        CompiledScript script = this.compile(source); 

        Object x = script.eval(context);

        return x;

    }

    @Override

    public Object eval(Reader source, ScriptContext context) throws ScriptException {

        CompiledScript script = this.compile(source); 

        Object x = script.eval(context);

        return x;

    }

    @Override

    public Bindings createBindings() {

        return new SymbolTableToBindingsAdapter(symbolTable);

    }

    @Override

    public CompiledScript compile(String script) throws ScriptException {

        Code code = this.manager.compile(script);

        CosaCompiledScript x = new CosaCompiledScript(this, code);

        return x;

    }

    @Override

    public CompiledScript compile(Reader script) throws ScriptException {

        List<String> lines;

        try {

            lines = IOUtils.readLines(script);

        } catch (IOException ex) {

            throw new ScriptException(ex);

        }

        String source = StringUtils.join(lines, "\n");

        return this.compile(source);

    }

    @Override

    public Object invokeMethod(Object thiz, String name, Object... args) throws ScriptException, NoSuchMethodException {

        throw new UnsupportedOperationException("Not supported yet."); 

    }

    @Override

    public Object invokeFunction(String name, Object... args) throws ScriptException, NoSuchMethodException {

        if( !this.interpreter.hasFunction(name) ) {

            throw new NoSuchMethodException(name);

        }

        try {

            return this.interpreter.call(name, args);

        } catch (Exception ex) {

            throw new ExpressionRuntimeException(this.interpreter.getCurrentCode(),"Error calling funcion '"+name+"'.", ex);

        }

    }

    @Override

    public <T> T getInterface(Class<T> clasz) {

        return null;

    }

    @Override

    public <T> T getInterface(Object thiz, Class<T> clasz) {

        return null;

    }

}