[Solved]-How do I deal with a ClassNotLoadedException while debugging?-eclipse

I faced the same problem, i just created a public static void main method, created object of same type and Run As java Application, i then removed main method, it now works fine.

By initializing GridSquare will solve the problem. squares =new GridSquare();

I have seen this happen in Eclipse when you have a subclass's class variables hiding a parent class's variables. Somehow that confuses Eclipse (and generally is a bad idea anyway :). For example:

class A {
   private String a;
}

class B extends A {
   public String a;
}

//Give a SIZE to the array:
GridSquare[] squares = GridSquare[this.theGrid.size()];

//Fill each element of the array with the object constructor to avoid the null value
for(int i=0; i<this.theGrid.size(); i++){
    squares[i] = new GridSquare();
    squares[i] = this.theGrid.getSquares(14, 18, 220, 222);
}

I ran into this error because I was running a unit test on code that uses reflection. I had made a special class for testing all the features of the code. Junit apparently uses a separate classloader for test classes (which makes perfect sense) so my code was not able to use reflection on that class. The stack trace I got was extremely generic (java.lang.InstantiationException) but when I checked in debug mode there was more detail on the Exception object itself (org.eclipse.debug.core.DebugException: com.sun.jdi.ClassNotLoadedException) which led me to this conclusion.

So I moved the special class to the main classloader (by moving the file from src/test/java to src/main/java) and it worked fine. I don't like this solution but I cannot figure out an alternative. In my case it's not a big deal but I can see how this might be a concern for others.