package com.voltvoodoo.brew;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.UnsupportedEncodingException;
import java.util.HashMap;
import java.util.Map;
import org.codehaus.plexus.util.IOUtil;
import org.mozilla.javascript.Context;
import org.mozilla.javascript.EvaluatorException;
import org.mozilla.javascript.Function;
import org.mozilla.javascript.JavaScriptException;
import org.mozilla.javascript.Scriptable;
import org.mozilla.javascript.ScriptableObject;
import org.mozilla.javascript.WrappedException;
public class JSRunner
{
private final ScriptableObject globalScope;
public JSRunner()
{
Context context = Context.enter();
context.setOptimizationLevel(-1); // Without this, Rhino hits a 64K bytecode limit and fails
try {
globalScope = context.initStandardObjects();
String[] names = { "print", "load", "readFile", "warn", "getResourceAsStream" };
globalScope.defineFunctionProperties(names, JSRunner.class, ScriptableObject.DONTENUM);
} finally {
Context.exit();
}
}
public void evalScript(String filename) {
if(!filename.startsWith( "/" )) {
filename = "/" + filename;
}
InputStream inputStream = getClass().getResourceAsStream(filename);
try {
try {
Reader reader = new InputStreamReader(inputStream, "UTF-8");
try {
Context context = Context.enter();
context.setOptimizationLevel(-1); // Without this, Rhino hits a 64K bytecode limit and fails
try {
context.evaluateReader(globalScope, reader, filename, 0, null);
} finally {
Context.exit();
}
} finally {
reader.close();
}
} catch (UnsupportedEncodingException e) {
throw new Error(e);
} finally {
inputStream.close();
}
} catch (IOException e) {
throw new Error(e);
}
}
public String evalString( String scriptString) throws IOException {
return evalString(scriptString, "Anonymous script", new HashMap<String,Object>());
}
public String evalString( String scriptString, String sourceName, Map<String, Object> objectsToPutInScope )
{
Context context = Context.enter();
try {
Scriptable compileScope = context.newObject(globalScope);
compileScope.setParentScope(globalScope);
for(String name : objectsToPutInScope.keySet()) {
compileScope.put( name, compileScope, objectsToPutInScope.get( name ));
}
return (String)context.evaluateString(
compileScope,
scriptString,
sourceName, 0, null);
} finally {
Context.exit();
}
}
//
// FUNCTIONS EXPOSED IN JS LAND
//
/**
* Print the string values of its arguments.
*
* This method is defined as a JavaScript function. Note that its arguments
* are of the "varargs" form, which allows it to handle an arbitrary number
* of arguments supplied to the JavaScript function.
*
*/
public static void print(Context cx, Scriptable thisObj, Object[] args, Function funObj) {
for (int i = 0; i < args.length; i++) {
if (i > 0) System.out.print(" ");
// Convert the arbitrary JavaScript value into a string form.
String s = Context.toString(args[i]);
System.out.print(s);
}
System.out.println();
}
public static void warn(Context cx, Scriptable thisObj, Object[] args, Function funObj) {
String message = Context.toString( args[ 0 ] );
int line = (int) Context.toNumber( args[ 1 ] );
String source = Context.toString( args[ 2 ] );
int column = (int) Context.toNumber( args[ 3 ] );
cx.getErrorReporter().warning( message, null, line, source, column );
}
/**
* This method is defined as a JavaScript function.
*/
public String readFile(String path) {
try {
return IOUtil.toString(getResourceAsStream(path));
} catch (RuntimeException exc) {
throw exc;
} catch (Exception exc) {
throw new RuntimeException("wrap: " + exc.getMessage(), exc);
}
}
/**
* Load and execute a set of JavaScript source files.
*
* This method is defined as a JavaScript function.
*
*/
public static void load(Context cx, Scriptable thisObj, Object[] args, Function funObj) {
for (Object element : args) {
String filename = Context.toString(element);
InputStreamReader in = null;
try {
in = new InputStreamReader(getResourceAsStream( filename ));
} catch( Exception e ) {
//Context.reportError("Couldn't open file \"" + filename + "\".");
throw new RuntimeException(e);
}
try {
// Here we evalute the entire contents of the file as
// a script. Text is printed only if the print() function
// is called.
cx.evaluateReader(thisObj, in, filename, 1, null);
} catch (WrappedException we) {
System.err.println(we.getWrappedException().toString());
we.printStackTrace();
} catch (EvaluatorException ee) {
System.err.println("js: " + ee.getMessage());
} catch (JavaScriptException jse) {
System.err.println("js: " + jse.getMessage());
} catch (IOException ioe) {
System.err.println(ioe.toString());
} finally {
try {
in.close();
} catch (IOException ioe) {
System.err.println(ioe.toString());
}
}
}
}
public static InputStream getResourceAsStream(String path) {
File file = new File(path);
if(file.exists()) {
try
{
return new FileInputStream(path);
}
catch ( FileNotFoundException e )
{
throw new RuntimeException(e);
}
} else {
if(path.startsWith( "./" )) {
path = path.substring( 2 );
}
return JSRunner.class.getClassLoader().getResourceAsStream( path );
}
}
}