Stack overflow error for large inputs in Java

The issue is most likely the recursive calls in DFSVisit. If you don't want to go with the 'easy' answer of increasing Java's stack size when you call the JVM, you may want to consider rewriting DFSVisit to use an iterative algorithm instead of recursive. While Depth First Search is more easily defined in a recursive manner, there are iterative approaches to the algorithm that can be used.

For example: this blog post

The stack is a region in memory that is used for storing execution context and passing parameters. Every time your code invokes a method, a little bit of stack is used, and the stack pointer is increased to point to the next available location. When the method returns, the stack pointer is decreased and the portion of the stack is freed up.

If an application uses recursion heavily, the stack quickly becomes a bottleneck, because if there is no limit to the recursion depth, there is no limit to the amount of stack needed. So you have two options: increase the Java stack (-Xss JVM parameter, and this will only help until you hit the new limit) or change your algorithm so that the recursion depth is not as deep.

I am not sure if you were looking for a generic answer, but from a brief glance at your code it appears that your problem is recursion.

If you're sure your algorithm is correct and the depth of recursive calls you're making isn't accidental, then solutions without changing your algorithm are:

• add to the JVM command line e.g. -Xss128m to set a 128 MB stack size (not a good solution in multi-threaded programs as it sets the default stack size for every thread not just the particular thread running your task);
• run your task in its own thread, which you can initialise with a stack size specific to just that thread (and set the stack size within the program itself)-- see my example in the discussion of fixing StackOverflowError, but essentially the stack size is a parameter to the Thread() constructor;
• don't use recursive calls at all-- instead, mimic the recursive calls using an explicit Stack or Queue object (this arguably gives you a bit more control).