Java调用javascript函数

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Java中自带库函数中有ScriptEngine可以支持javascript等script文件

        ScriptEngineManager manager = new ScriptEngineManager();
        //ScriptEngineManager可以理解为一个工厂，根据你输入的语言名字，返回调用的函数库。
        ScriptEngine jsEngine = manager.getEngineByName("javascript");
        String jsFileName = "sha256.js";
        FileReader reader = new FileReader(jsFileName);
        //通过eval函数读取Engine实例
        jsEngine.eval(reader);
        String str = null;
        if (jsEngine instanceof Invocable) {
            Invocable invoke = (Invocable) jsEngine;
        //SHA256是js中的function名字。
            str = (String) invoke.invokeFunction("SHA256", toSha);
        }
        reader.close();
        return str;
    }

另外在Spring中对该函数进行了封装，如下：

//script type
String scriptType = "javascript";

//script source
String scriptSource = "console.log();";

//argument
Map<String, Object> arguments = new HashMap<>();
argument.put("argument1", "Hello World");

StandardScriptEvaluator evaluator = new StandardScriptEvaluator();

//set script type
evaluator.setLanguage(scriptType);

//execute the script
evaluator.evaluate(new StaticScriptSource(scriptSource), argument);