[javascript] view plain copy
function formula(var1,var2){
return var1+var2-factor
}
java代码如下：
[java] view plain copy
import java.io.FileNotFoundException
import java.io.FileReader
import java.util.Scanner
import javax.script.Bindings
import javax.script.Invocable
import javax.script.ScriptContext
import javax.script.ScriptEngine
import javax.script.ScriptEngineManager
import javax.script.ScriptException
public class AboutJavaScript {
public static void main(String[] args) throws Exception {
ScriptEngine engine=new ScriptEngineManager().getEngineByName("javascript")
Bindings bind = engine.createBindings()
bind.put("factor", 1)
engine.setBindings(bind, ScriptContext.ENGINE_SCOPE)
Scanner input=new Scanner(System.in)
while (input.hasNextInt()) {
int first= input.nextInt()
int sec=input.nextInt()
System.out.println("输入参数是："+first+","+sec)
engine.eval(new FileReader("F:/model.js"))
if(engine instanceof Invocable){
Invocable in =(Invocable) engine
Double result=(Double) in.invokeFunction("formula", first,sec)
System.out.println("运行结果："+result.intValue())
}
}
}
}
JDK1.6版添加了新的ScriptEngine类，允许用户直接执行js代码。在Java中直接调用js代码
不能调用浏览器中定义的js函数，会抛出异常提示ReferenceError: “alert” is not defined。
package com.sinaapp.manjushri
import javax.script.ScriptEngine
import javax.script.ScriptEngineManager
import javax.script.ScriptException /** * 直接调用js代码 */
public class ScriptEngineTest {
public static void main(String[] args) {
ScriptEngineManager manager = new ScriptEngineManager()
ScriptEngine engine = manager.getEngineByName("javascript")
try{
engine.eval("var a=3var b=4print (a+b)")
// engine.eval("alert(\"js alert\")") // 不能调用浏览器中定义的js函数 // 错误，会抛出alert引用不存在的异常
}catch(ScriptException e){
e.printStackTrace()
}
}
}
可参考：package javaIjs
/**
* @param args
*/
import java.io.FileReader
import javax.script.Invocable
import javax.script.ScriptEngine
import javax.script.ScriptEngineManager
/**
* Java调用并执行js文件，传递参数，并活动返回值
*
* @author manjushri
*/
public class ScriptEngineTest {
public static void main(String[] args) throws Exception {
ScriptEngineManager manager = new ScriptEngineManager()
ScriptEngine engine = manager.getEngineByName("javascript")
String jsFileName = System.getProperty("user.dir")+"/src/javaIjs/expression.js"
// 读取js文件
FileReader reader = new FileReader(jsFileName)
// 执行指定脚本
System.out.println(engine.getContext().getReader())
engine.eval(reader)
if (engine instanceof Invocable) {
Invocable invoke = (Invocable) engine
// 调用merge方法，并传入两个参数
// c = merge(2, 3)
Double c = (Double) invoke.invokeFunction("merge1", 21, 3)
System.out.println("c = " + c)
}
reader.close()
}
}
