通过其参数调用不同的方法 [英] Call different methods by its parameter

问题描述

我有一个应用程序，该应用程序应根据参数的输入调用不同的方法.到目前为止，我的想法基本上是，我创建一个Switch并根据其大小分别调用方法.示例:

I got an application which should call different methods, based on the params' input. My idea until now is basically, that I create a Switch and call the methods separately by its case. Example:

switch (methodName)
{
    case "method1":
        method1();
        break;
    case "method2":
        method2();
        break;
    default:
        System.out.println(methodName + " is not a valid method!");
}

我正在考虑通过给定的字符串来调用该方法的选项，如本问题所述:

I was considering the option to invoke the method by its given string, as provided in this question:

在给定方法名称为字符串的情况下如何调用Java方法?

但是我从其中一个答案中得知，这是不安全的.你们怎么看?

But then I read from one of the answers, that it's not safe. What do you guys think?

推荐答案

如果您需要从字符串转到方法调用，则反射可能是您的最佳选择.不会涉及重大安全问题，尤其是如果您限制允许调用的方法集时.使用Map<String, Method>是实现它的一种方法，它具有改进的性能，因为主要瓶颈不是反射方法调用，而是方法查找.

If you need to go from a string to a method call, reflection may be your best option. There are no great safety issues involved, especially if you constrain the set of methods that are allowed to be called. Using a Map<String, Method> is one way to achieve it, with the benefit of improved performance since the main bottleneck is not reflective method invocation, but method lookup.

无需反思，您可以使用Map<String, Callable>实现此目标，其中您为每个方法调用使用匿名类实例实现Callable.样板代码要多一些，但是类型安全".

Without reflection you could achieve this with a Map<String, Callable>, where you implement Callable with an anonymous class instance for each method call. Quite a bit more boilerplate code, but "type safe".

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