java - 通过 Nashorn 执行 uglifyJs2

Question

我通过 uglifyjs --self 提取了 uglifyJs2，我正在尝试使用 uglify.js 缩小 app.js。我希望至少应该将缩小的 js 生成到新文件或控制台中，但现在它不起作用。我应该如何使用 uglify.min.js 缩小 app.js？

public static void main(String[] args) throws Exception {
    ScriptEngine scriptEngine = new ScriptEngineManager().getEngineByName("nashorn");
    Bindings bindings = new SimpleBindings();
    bindings.put("console", System.console());
    executeJs("uglifyjs.min.js",scriptEngine, bindings);
    String res = (String) invocable.invokeFunction("UglifyJS.parse(code)", code);
   //Here I got NoSuchMethodException: No such function UglifyJS.parse(code)
}

static String readFile(String path, Charset encoding)
        throws IOException
{
    byte[] encoded = Files.readAllBytes(Paths.get(path));
    return new String(encoded, encoding);
}

private static void executeJs(String fileName, ScriptEngine engine, Bindings bindings) throws Exception {
    String test = readFile(fileName, StandardCharsets.UTF_8);
    engine.put(ScriptEngine.FILENAME, fileName);
    engine.eval(test, bindings);
}

当我去的时候

Answer 1

invokeFunction 只能用于调用全局函数。它不能像上面那样用于评估任意代码。以下将起作用:

// define a global function that accepts one arg and invoke UglifyJS.parse on it
scriptEngine.eval("function func(code) { return UglifyJS.parse(code) }");

// call the newly defined global function "func"
invocable.invokeFunction("func", code);