public Process nextPriority() {
		//process to return
		Process the_selected_process = null;


		for(int i = 0; i < priority_four.size(); i++) {
			if(priority_four.get(i).getState() != Process.State.BLOCKED ) {
				the_selected_process = priority_four.get(i);
				return the_selected_process;
			}   
		}

		for(int i = 0; i < priority_three.size(); i++) {
			if(priority_three.get(i).getState() != Process.State.BLOCKED ) {
				the_selected_process = priority_three.get(i);
				return the_selected_process;
			}   
		}

		for(int i = 0; i < priority_two.size(); i++) {
			if(priority_two.get(i).getState() != Process.State.BLOCKED ) {
				the_selected_process = priority_two.get(i);
				return the_selected_process;
			}   
		}

		for(int i = 0; i < priority_one.size(); i++) {
			if(priority_one.get(i).getState() != Process.State.BLOCKED ) {
				the_selected_process = priority_one.get(i);
				return the_selected_process;
			}   
		}

		//null if no processes in any priority list
		return null;
	}