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Weird Question
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Is there any way that I can take a String and somehow use it as if its the name of one of my declared Objects? For example, if I have an Animal named germanShephard, is there some way I could say String gerSh = "germanShephard"; and then treat gerSh as if it was the equivalent of saying germanShephard in my program?
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Posting Whiz in Training
Beforehand I'm sorry for my English...
I don't know any way to dynamically create variable, but I can offer some alternatives:
1. Use Dictionary
2. Create class variable dynamicly
I don't know any way to dynamically create variable, but I can offer some alternatives:
1. Use Dictionary
2. Create class variable dynamicly
So what if you can see the darkest side of me?
No one would ever change this animal I have become
Help me believe it's not the real me
Somebody help me tame this animal
No one would ever change this animal I have become
Help me believe it's not the real me
Somebody help me tame this animal
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Junior Poster in Training
Java doesn't support creating variable names dynamically.
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Posting Shark
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Originally Posted by BestJewSinceJC 
Is there any way that I can take a String and somehow use it as if its the name of one of my declared Objects? For example, if I have an Animal named germanShephard, is there some way I could say String gerSh = "germanShephard"; and then treat gerSh as if it was the equivalent of saying germanShephard in my program?
Dictionary is also an okay way to go, but I believe it is a deprecated API (or incredibly outdated).
Edit: Actually, you can probably get away with using a Pair<K, V> instead of something that handles an entire collection.
I'm not sure where it is defined in the Java Standard Library, but if all else fails you can easily create your own pair class.
Last edited by Alex Edwards; Nov 8th, 2008 at 9:03 pm.
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> For example, if I have an Animal named germanShephard, is there some way I could say
> String gerSh = "germanShephard"; and then treat gerSh as if it was the equivalent of
> saying germanShephard in my program?
You can't because gerSh is now a String. The closest you can come to this kind of name to Object mapping is by using a Map or by using the reflection API, which again doesn't work for `private' members.
The behavior you speak of can be seen in all ECMAScript implementations. Something of the sort:
> String gerSh = "germanShephard"; and then treat gerSh as if it was the equivalent of
> saying germanShephard in my program?
You can't because gerSh is now a String. The closest you can come to this kind of name to Object mapping is by using a Map or by using the reflection API, which again doesn't work for `private' members.
The behavior you speak of can be seen in all ECMAScript implementations. Something of the sort:
Java Syntax (Toggle Plain Text)
The romantic image of an über-programmer is someone who fires up Emacs, types like a machine gun, and delivers a flawless final product from scratch. A more accurate image would be someone who stares quietly into space for a few minutes and then says “Hmm. I think I’ve seen something like this before.” - John D
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I've used reflection before but I don't understand how it helps solve my problem. It just lets me know about certain properties of an Object, such as its classname. The concept of a Map is somewhat familiar, but it doesn't help avoid the work, does it? The primary reason I'd want to do this is b/c it'd be less work. For example, if I had 200 buttons, button1-button200, it'd be useful if I could do what I described in my first post. I guess this isn't possible in Java though.
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Junior Poster in Training
If you have two hundred buttons you should store them in an array.
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I agree, but that isn't what I asked. Anyway, thanks for your help everybody. If anyone knows any languages where you can do this, please let me know, with a code example if you would. Otherwise consider this topic closed.
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Junior Poster in Training
I still don't understand the question entirely, but in many scripting languages you can evaluate any given string as if it were code.
Example in Ruby:
Anyway, except when metaprogramming, this technique should be used very sparingly. There aren't many good reasons to do this.
And sorry if I misinterpreted your question.
Example in Ruby:
Ruby Syntax (Toggle Plain Text)
Anyway, except when metaprogramming, this technique should be used very sparingly. There aren't many good reasons to do this.
And sorry if I misinterpreted your question.
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I think you answered my question correctly in your first post. I was just asking if it is possible to save a value into a String, then use that String as if it was the name of an Object (rather than being a String).
So, for example, if I had a String buttonName = "button1"; then I was asking if I could do
buttonName.whatever(), and have buttonName evaluate itself to see whether or not there was an Object named "button1" in the program. If so, it would call whatever().
Now obviously, this doesn't work as I wrote it, since Java treats buttonName as a String (as it should). I was just asking if there were any techniques that would do what I described above.
So, for example, if I had a String buttonName = "button1"; then I was asking if I could do
buttonName.whatever(), and have buttonName evaluate itself to see whether or not there was an Object named "button1" in the program. If so, it would call whatever().
Now obviously, this doesn't work as I wrote it, since Java treats buttonName as a String (as it should). I was just asking if there were any techniques that would do what I described above.
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