JDK1.7中调用javascript方法

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");
    }
}