java与脚本引擎

1. 获得脚本引擎对象

//获得脚本引擎对象
ScriptEngineManager sem = new ScriptEngineManager();
ScriptEngine engine = sem.getEngineByName("javascript");

2. javascript脚本引擎——Rhino
   网站：https://developer.mozilla.org/en-US/docs/Mozilla/Projects/Rhino

例子

import java.io.FileReader;
import java.io.IOException;
import java.net.URL;
import java.util.List;

import javax.script.Invocable;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;

public class Test {

  public static void main(String[] args) {
    ScriptEngineManager sem = new ScriptEngineManager();
    ScriptEngine engine = sem.getEngineByName("javascript");

    engine.put("msg", "但使龙城飞将在，不教胡马度阴山");
    String str = "var man= {name:'汉将军李广',age:18,skills:['飞刀','骑射']};";
    str += "print(man.name)";

    try {
      // 执行脚本
      engine.eval（str);

      // 操作属性
      engine.eval（"msg='飞将军是卫青';");
      System.out.println(engine.get("msg"));

      System.out.println("----------------------");

      // 执行函数
      engine.eval（"function add(a,b){var sum=a+b;return sum;}");
      Invocable jsInvoke = (Invocable) engine;
      Object ret = jsInvoke.invokeFunction("add", new Object[] { 10, 20 });
      System.out.println(ret);

      System.out.println("----------------------");

      // 导入java包，使用包中的类
      String jsCode = "var list = java.util.Arrays.asList([\"北京\",\"南京\",\"西安\"]);";
      engine.eval（jsCode);
      List<String> list2 = (List<String>) engine.get("list");
      for (String ls : list2) {
        System.out.println(ls);
      }

      System.out.println("----------------------");

      // 执行js脚本文件
      URL url = Test.class.getClassLoader().getResource("test.js"); // 项目src目录下——即 System.getProperty("java.class.path")
      FileReader fr = new FileReader(url.getPath());
      engine.eval（fr);
      fr.close();

    } catch (ScriptException | NoSuchMethodException | IOException e) {
      e.printStackTrace();
    }
  }

}