Java調用javascript函數

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Java中自帶庫函數中有ScriptEngine可以支持javascript等script文件

        ScriptEngineManager manager = new ScriptEngineManager();
        //ScriptEngineManager可以理解為一個工廠，根據你輸入的語言名字，返回調用的函數庫。
        ScriptEngine jsEngine = manager.getEngineByName("javascript");
        String jsFileName = "sha256.js";
        FileReader reader = new FileReader(jsFileName);
        //通過eval函數讀取Engine實例
        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中對該函數進行了封裝，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);