jdk1.6执行JavaScript好慢啊

最新推荐文章于 2021-02-13 19:28:19 发布

原创最新推荐文章于 2021-02-13 19:28:19 发布 · 1.4k 阅读

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文章标签：

#javascript #jdk #exception #string #function #import

本文通过一个简单的示例程序测试了JDK 1.6中JavaScript的执行性能，并发现对于10000次乘法运算，耗时达到了0.75秒，表明其性能不足以用于游戏脚本等高性能需求场景。

本来想既然jdk1.6已经支持JavaScript了，那我用这个来做游戏的脚本语言岂不是更好，写了段代码测试JavaScript的执行速度，结果让人失望。

10000次乘法运算，居然耗时达到0.75秒，当然期间还有一些对象转换等，不过总的来说，这个性能是不可用的。

import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.util.List; import javax.script.Invocable; import javax.script.ScriptEngine; import javax.script.ScriptEngineFactory; import javax.script.ScriptEngineManager; import javax.script.ScriptException; import javax.swing.JButton; import javax.swing.JFrame; public class TestScript implements ActionListener{ ScriptEngineManager sem; ScriptEngine engine; Invocable inv; public TestScript() { sem = new ScriptEngineManager(); List<ScriptEngineFactory> list = sem.getEngineFactories(); for (int i = 0; i< list.size(); i++) { ScriptEngineFactory sef = list.get(i); System.out.println("Engine Name=" + sef.getEngineName() + ", scrip = " + sef.getLanguageName()); } engine = sem.getEngineByName("javascript"); initEngine(); inv = (Invocable)engine; } private void initEngine() { try { String script = "function calc(value) { return value*value;}"; engine.eval(script); } catch(ScriptException se) { se.printStackTrace(); } } @Override public void actionPerformed(ActionEvent e) { // TODO Auto-generated method stub try { test(); } catch(Exception ex) { ex.printStackTrace(); } } private void test() throws ScriptException, NoSuchMethodException { int N = 10000; long t0 = System.currentTimeMillis(); double result = 0; for (int i = 0; i< N; i++) { result = testCalc(i); } System.out.println("time =" + (System.currentTimeMillis() - t0)*1.0/1000); result = result*2; } private Double testCalc(int v) throws ScriptException, NoSuchMethodException { return (Double)inv.invokeFunction("calc", v); } /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub JFrame f = new JFrame(); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.setSize(640, 480); JButton btn = new JButton("Run Test"); TestScript sc = new TestScript(); btn.addActionListener(sc); f.getContentPane().add(btn, "North"); f.setVisible(true); } }