import java.io.File;import javax.script.Invocable;import javax.script.ScriptEngine;import javax.script.ScriptEngineManager;import javax.script.ScriptException;public class TestJs {    public static void main(String[] args) throws Exception {        ScriptEngineManager manager = new ScriptEngineManager();        ScriptEngine engine = manager.getEngineByName("JavaScript");        testScriptVariables(engine);// 演示如何暴露Java对象为脚本语言的全局变量        testInvokeScriptMethod(engine);// 演示如何在Java中调用脚本语言的方法        testScriptInterface(engine);// 演示脚本语言如何实现Java的接口        testUsingJDKClasses(engine);// 演示脚本语言如何使用JDK平台下的类    }    public static void testScriptVariables(ScriptEngine engine)            throws ScriptException {        File file = new File("test.txt");        engine.put("f", file);        engine.eval("println(‘Total Space:‘+f.getTotalSpace())");    }    public static void testInvokeScriptMethod(ScriptEngine engine)            throws Exception {        String script = "function hello(name) { return ‘Hello,‘ + name;}";        engine.eval(script);        Invocable inv = (Invocable) engine;        String res = (String) inv.invokeFunction("hello", "Scripting");        System.out.println("res:" + res);    }    public static void testScriptInterface(ScriptEngine engine)            throws ScriptException {        String script = "var obj = new Object(); obj.run = function() { println(‘run method called‘); }";        engine.eval(script);        Object obj = engine.get("obj");        Invocable inv = (Invocable) engine;        Runnable r = inv.getInterface(obj, Runnable.class);        Thread th = new Thread(r);        th.start();    }    public static void testUsingJDKClasses(ScriptEngine engine)            throws Exception {        // Packages是脚本语言里的一个全局变量,专用于访问JDK的package        String js = "function doSwing(t){var f=new Packages.javax.swing.JFrame(t);f.setSize(400,300);f.setVisible(true);}";        engine.eval(js);        Invocable inv = (Invocable) engine;        inv.invokeFunction("doSwing", "Scripting Swing");    }}