使用字符串设置属性

Question

Is it possible to set a property on an object using a string as the property name? I am quite new to Java but in JavaScript I would just do something like this:

 Object[propertyNameAsString] = value

After searching around I found how to get a property using a string, but not how to set one. I also came across something called a Properties object, is that what I need to be using?

Basically I just want to loop through an array filled with image names and then set their respective properties onto an object which I will use to store the actual images. Is this possible in Java or should I do it another way?

Edit:

This is what my array looks like:

 static String pngs[] = {"staminaBox", "staminaBoxR", "healthBox", "healthBoxR", "moveBox", "goButton"};

Ideally I want to loop through them and add properties to an assets class like so:

 for (int i = 0; i < pngs.length; i++) {
    Assets.pngs[i] = createImageFromUrl(pngs[i] + ".png");      
 }

But now I'm realizing this wouldn't work because in my assets class I have to previously define the properties like:

 public static Image staminaBox;

And the whole point of me wanting to do this in the first place was so that I didn't have to write out declarations for every single image I wanted to add. I'm used to the loose nature of JavaScript, but does this mean there is no way of getting around these explicit declarations of properties? Will a HashMap let me accomplish this?

Answer 1

You might be talking about a couple different things. Are you talking about setting the value of variables defined inside a class? If so, you might be able to hack something together using reflection, but it's not a "gimme" in Java like it is in javascript.

You might also look into using a HashMap of properties to their values, or like you said, the Properties object (which is pretty much just a Map itself).

Answer 2

You can use the Reflection API. Keep in mind that it will get messy very quickly.

Because Java uses the Getter and Setter pattern, you likely won't be assigning a value to a member variable but calling a method which itself assigns the value.

How do I invoke a Java method when given the method name as a string?