Java engine

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.util.List;

import javax.print.DocFlavor.URL;
import javax.script.Invocable;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;


@SuppressWarnings ( "all") // suppress all warnings
public class Engine_GetRhino {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		// get the script engine
		ScriptEngineManager sem = new ScriptEngineManager();
		ScriptEngine engine=sem.getEngineByName("javascript");
		
		// define variables stored in the context engine
		engine.put("msg", "you are very good");
		
		String str = "var user = {name: 'waibizi', age: 18, schools: [ 'Zhaoqing', 'Computer Science']};";
		str += "print(user.name);";
		
		
		
		// execute the script
		try {
			engine.eval(str);
			engine.eval("msg='you are very bad';");
		} catch (ScriptException e) {
			// TODO Auto-generated catch block
			e.printStackTrace ();
		}
		
		// Test output
		System.out.println(engine.get("msg"));
		
		
		
		try {
			// define the function
			engine.eval("function add(a,b){var sum = a + b; return sum;}");
			engine.eval("function add1(){var sum = 123 + 321; return sum;}");
			// function execution
			Invocable jsInvoke = (Invocable) engine;
			Object result = jsInvoke.invokeFunction ( "add", new Object [] {15,13}); // specifies the function assignment
			Object result1 = jsInvoke.invokeFunction ( "add1"); // specify the function assignment
			System.out.println(result);
			System.out.println(result1);
			
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace ();
		}
		
		
		
		try {
			// js import java package using java class
			
// The following code is commented out JDK1.6, the first has been abandoned, did not see the comment below
// String jsCode = "importPackage (java.util); var list = Arrays.asList ([\" Zhaoqing University \ "\" School of Computer Science \ ", \" Software Engineering \ "]);"; 
			
			String jsCode = "var list = java.util.Arrays.asList ([\" Zhaoqing University \ "\" School of Computer Science \ ", \" Software Engineering \ "]);";
			engine.eval(jsCode);
			List list = (List) engine.get("list");
			for(int i=0;i<list.size();i++) {
				System.out.println(list.get(i));
			}
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace ();
		}
		
		
		try {
			java.net.URL url = Engine_GetRhino.class.getClassLoader().getResource("demo.js");
			FileReader fr = new FileReader(url.getPath());
			engine.eval(fr);
			fr.close (); // Since only a test, not so standardized. We have to use try catch finally the actual use!
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace ();
		}

	}

}

 

 

 a.js follows

 

function test(){
	There are a = 666;
	print("invoke js file:"+a);
}

test();