Probing

Tracing can be accomplished by probing the state of execution. Execution can be watched (or recorded) by printing the location of execution and the state of instance variables.

	for(int i=0; i < array.length; i++){
		System.out.print("At index: "+i+" "+a[i]);
	}

We can probe the state of all objects in the array during execution. This would allow us to determine if values contain the "expected" values. This method of debugging is a valuable skill once you know the location of the bug. Probing does require that a class implements the toString() so that you can meaningfully print the state of an object.