java eval javascript jsr22

文章来源：csdn 龙四哥 ticmy

http://www.ticmy.com/?p=267

需要导入的包

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

第一种方式

ScriptEngineManager scriptEngineManager = new ScriptEngineManager();
ScriptEngine scriptEngine = scriptEngineManager.getEngineByName("javascript");
String exp = "a+b";
scriptEngine.put("a", 4);
scriptEngine.put("b", 15);
Object result = scriptEngine.eval(exp);
System.out.println(exp + "=" + result);

第二种方式

ScriptEngineManager scriptEngineManager = new ScriptEngineManager();
ScriptEngine scriptEngine = scriptEngineManager.getEngineByName("javascript");
String exp = "2*6-(6+5)";
Object result = scriptEngine.eval(exp);
System.out.println(exp + "=" + result);