Java CompilationUnit类代码示例

import org.codehaus.janino.Java.CompilationUnit; //导入依赖的package包/类
private CompilationUnit get(Class<?> c) throws IOException {
    URL u = getSourceURL(c);
    try (Reader reader = Resources.asCharSource(u, UTF_8).openStream()) {
      String body = CharStreams.toString(reader);

      // TODO: Hack to remove annotations so Janino doesn't choke. Need to reconsider this problem...
      body = body.replaceAll("@\\w+(?:\\([^\\\\]*?\\))?", "");
      for(Replacement r : REPLACERS){
        body = r.apply(body);
      }
//       System.out.println("original");
      // System.out.println(body);;
      // System.out.println("decompiled");
      // System.out.println(decompile(c));

      try {
        return new Parser(new Scanner(null, new StringReader(body))).parseCompilationUnit();
      } catch (CompileException e) {
        logger.warn("Failure while parsing function class:\n{}", body, e);
        return null;
      }

    }

  }
 

import org.codehaus.janino.Java.CompilationUnit; //导入依赖的package包/类
private CompilationUnit get(Class<?> c) throws IOException{
  String path = c.getName();
  path = path.replaceFirst("\\$.*", "");
  path = path.replace(".", FileUtils.separator);
  path = "/" + path + ".java";
  CompilationUnit cu = functionUnits.get(path);
  if(cu != null) {
    return cu;
  }

  URL u = Resources.getResource(c, path);
  InputSupplier<InputStream> supplier = Resources.newInputStreamSupplier(u);
  try (InputStream is = supplier.getInput()) {
    if (is == null) {
      throw new IOException(String.format("Failure trying to located source code for Class %s, tried to read on classpath location %s", c.getName(), path));
    }
    String body = IO.toString(is);

    //TODO: Hack to remove annotations so Janino doesn't choke.  Need to reconsider this problem...
    body = body.replaceAll("@\\w+(?:\\([^\\\\]*?\\))?", "");
    try{
      cu = new Parser(new Scanner(null, new StringReader(body))).parseCompilationUnit();
      functionUnits.put(path, cu);
      return cu;
    } catch (CompileException e) {
      logger.warn("Failure while parsing function class:\n{}", body, e);
      return null;
    }

  }

}
 

import org.codehaus.janino.Java.CompilationUnit; //导入依赖的package包/类
private void checkInit() {
    count.incrementAndGet();
    if (ready) {
      return;
    }

    synchronized (this) {
      if (ready) {
        return;
      }

      // get function body.

      try {
        final Class<?> clazz = Class.forName(className);
        final CompilationUnit cu = get(clazz);

        if (cu == null) {
          throw new IOException(String.format("Failure while loading class %s.", clazz.getName()));
        }

        methods = ImmutableMap.copyOf(MethodGrabbingVisitor.getMethods(cu, clazz));
        if(methods.isEmpty()){
          throw UserException.functionError()
          .message("Failure reading Function class. No methods were found.")
          .addContext("Function Class", className)
          .build(logger);
        } else {
//          logger.warn("{} Methods for class {} loaded. Methods available: {}", methods.size(), className, methods.entrySet());
        }
        ready = true;
      } catch (IOException | ClassNotFoundException e) {
        throw UserException.functionError(e)
            .message("Failure reading Function class.")
            .addContext("Function Class", className)
            .build(logger);
      }
    }
  }
 

import org.codehaus.janino.Java.CompilationUnit; //导入依赖的package包/类
/**
 * Loads function body: methods (for instance, eval, setup, reset) and imports.
 * Loading is done once per class instance upon first function invocation.
 * Double-checked locking is used to avoid concurrency issues
 * when two threads are trying to load the function body at the same time.
 */
private void loadFunctionBody() {
  if (isLoaded) {
    return;
  }

  synchronized (this) {
    if (isLoaded) {
      return;
    }

    logger.trace("Getting function body for the {}", className);
    try {
      final Class<?> clazz = Class.forName(className, true, classLoader);
      final CompilationUnit cu = convertToCompilationUnit(clazz);

      methods = MethodGrabbingVisitor.getMethods(cu, clazz);
      imports = ImportGrabber.getImports(cu);
      isLoaded = true;

    } catch (IOException | ClassNotFoundException e) {
      throw UserException.functionError(e)
          .message("Failure reading Function class.")
          .addContext("Function Class", className)
          .build(logger);
    }
  }
}
 

import org.codehaus.janino.Java.CompilationUnit; //导入依赖的package包/类
/**
 * Using class name generates path to class source code (*.java),
 * reads its content as string and parses it into {@link org.codehaus.janino.Java.CompilationUnit}.
 *
 * @param clazz function class
 * @return compilation unit
 * @throws IOException if did not find class or could not load it
 */
private CompilationUnit convertToCompilationUnit(Class<?> clazz) throws IOException {
  String path = clazz.getName();
  path = path.replaceFirst("\\$.*", "");
  path = path.replace(".", DrillFileUtils.SEPARATOR);
  path = "/" + path + ".java";

  logger.trace("Loading function code from the {}", path);
  try (InputStream is = clazz.getResourceAsStream(path)) {
    if (is == null) {
      throw new IOException(String.format(
          "Failure trying to locate source code for class %s, tried to read on classpath location %s", clazz.getName(),
          path));
    }
    String body = IO.toString(is);

    // TODO: Hack to remove annotations so Janino doesn't choke. Need to reconsider this problem...
    body = body.replaceAll("@\\w+(?:\\([^\\\\]*?\\))?", "");
    try {
      return new Parser(new Scanner(null, new StringReader(body))).parseCompilationUnit();
    } catch (CompileException e) {
        throw new IOException(String.format("Failure while loading class %s.", clazz.getName()), e);
    }

  }

}