Question

I’m using a recursive function, and I’m getting this error when I execute :

Exception in thread "main" java.lang.StackOverflowError
    at java.util.HashMap$Entry.<init>(Unknown Source)
    at java.util.HashMap.addEntry(Unknown Source)
    at java.util.HashMap.put(Unknown Source)

I debeugged the method and 100% sure it ends at some point.

So I think its related to a memory problem.

Is there any solution ?

EDIT:

public static Vector<String> _toOpen;

public static void openFiles(Vector<String> files)
{       
   ...

    while(actualFile.hasNext)
    {
        if(!_toOpen.contains(word))
        {
           _toOpen.add(word);
            System.out.println("word");
        }
    }

   ...

   if(_toOpen.size() > 0)
   {
       openFiles(_toOpen);
   }
}

At the first call I pass to OpenFiles a Vector wich contains a list of files to open, each file has a list of files to open again and so on …

What I’m doing is preventing a file to be opened if it was dopne before.

Answer 1

Looking at your code – is there any conditional (e.g. if for example) on your final call to openFiles(_toOpen)?

If not, then every time openFiles is called, it will call itself recursively. No matter what the maximum size of the stack, this method will never actually return and you’ve effectively got an infinite loop.

And if there is some conditional beforehand, you’re evidently getting into a situation where it’s consistently evaluating to a true (or whatever leads to the recursive call being made).

---

Asides from that, it looks like you could restructure your code to avoid this. What it is you’re trying to do with _toOpen? Why do you appear to ignore the files argument passed in (I appreciate there is elided code, and presumably the contents get copied to _toOpen, but this seems unusual to say the least).

A recursive call does not seem like it’s the best way to approach this problem, unless you have some strange situation such as files that refer to other files to open.