java动态代码方案

方案一：

https://vimsky.com/examples/detail/java-class-javax.script.Invocable.html
import javax.script.Invocable; //导入依赖的package包/类
public Object executeJs(String js,@Nullable String funcName,Object... args){
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("javascript");
    try {
        Object res=engine.eval(js);
        if(StringUtils.isNotBlank(funcName)){
            if (engine instanceof Invocable) {
                Invocable invoke = (Invocable) engine;
                res = invoke.invokeFunction(funcName, args);
            }
        }
        return res;
    } catch (Exception e) {
        log.error("",e);
    }
    return null;
}

方案二
https://www.jb51.net/article/209651.htm
1.导包

2、demo实例

private String condition(){
	// 用于存储参数
	MapContext context = new MapContext();
	context.set("strA",1);
	context.set("strB",2);
	// 动态脚本（里面的参数都需要存储在context）
	String condition  = "strA <= strB ? \"yes\" : \" No\"";
	JexlExpression expression  = new Engine().createExpression(condition  );
	return expression .evaluate(context).toString();
}

@Test
private void test(){
String condition =  condition()；
System.out.println(condition);
}