public static void main(String[] args) {      CashRegister myCashRegister = new CashRegister();      Item item = myCashRegister.getItem(123456);    public class CashRegister {     public Item getItem(int barcode) {         return this.getItem(barcode);     }    public class Item {      public int getBarcode(){         return barcode;     }   I am creating an item object in main and trying to get the item's barcode through a Cash Register class. I end up getting "Exception in thread "main" java.lang.StackOverflowError".  I do have a getBarcode method in the item class, but kept getting errors because barcode is an int, and so I cannot return an int for the Item getItem method.  Please put me in the right direction towards getting the item's barcode. Thank you.
What is a StackOverflowError, what causes it, and how should I deal with them?
How To Delete This Red Box on My Screen? I was editing my mesh and I wanted to only see a part of my mesh, so I pressed alt+B to only show a selected area. However, I did ctrl+B and created a red rectangle on my screen (I don't know what it does). Does anybody know how to get it off? We have been asked to prove the above statement through the two sub-proofs:   Firstly we must prove that $e^x$ is increasing and then prove that $\log(x)$ is also an increasing function.   After we are asked to prove that using the delta-epsilion definition of a limit that $\lim_{x \to 0} e^x = 1$.   I have done all of this but still don't see where the instructor is going with this. Is a rational-valued continuous function $f\colon[0,1]\to\mathbb{R}$ constant? Let $f\colon[0,1]\to\mathbb{R}$ be continuous such that $f(x)\in\mathbb{Q}$ for any $x\in[0,1]$. Intuitively I feel that $f$ is constant, since $\mathbb{Q}$ is dense in $\mathbb{R}$.  How can I formally write this down? mysqli_fetch_assoc() expects parameter / Call to a member function bind_param() errors. How to get the actual mysql error and fix it? Scale Image Using PHP and Maintaining Aspect Ratio I'm using Ubuntu 12.04.3 with NVidia drivers (319) for my Quadro K2100M graphic card, and when I switch my main 3200x1800 laptop screen to mode 1920x1080 (using nvidia-settings), the display goes blurry...  I am using two screens:    My main screen is a LCD with max resolution 1920x1200. My laptop screen (original resolution 3200x1800) is sitting to the right of that.   The main problem is that, on Ubuntu, the font is far too small on my laptop screen. Because of that, I wanted to change the resolution of my laptop to 1920x1080.  Reading , I tried to  and here is the DPI configuration which I should have:   94x94 for my main LCD screen 1920x1200 235x236 for my 3200x1800 laptop screen   Is there a way to have dual DPI resolutions with an extended desktop? So, the spiffy new wi-fi thermostats want power on the C wire from thermostat, but the old thermostat doesn't have a C wire at it.  What's the easiest way to add the C wire/24 volt to the thermostat location? When a 'blur' event occurs, how can I find out which element focus went *to*? Suppose I attach an blur function to an HTML input box like this:  &lt;input id="myInput" onblur="function() { ... }"&gt;&lt;/input&gt;   Is there a way to get the ID of the element which caused the blur event to fire (the element which was clicked) inside the function? How?  For example, suppose I have a span like this:  &lt;span id="mySpan"&gt;Hello World&lt;/span&gt;   If I click the span right after the input element has focus, the input element will lose its focus. How does the function know that it was mySpan that was clicked?  PS: If the onclick event of the span would occur before the onblur event of the input element my problem would be solved, because I could set some status value indicating a specific element had been clicked.  PPS: The background of this problem is that I want to trigger an AJAX autocompleter control externally (from a clickable element) to show its suggestions, without the suggestions disappearing immediately because of the blur event on the input element. So I want to check in the blur function if one specific element has been clicked, and if so, ignore the blur event. In attempting to wrap my mind around the basic vocabulary, concepts, and methods of philosophy, I find myself wondering what the difference is between a philosopher and a theologian.   can have two meanings: 1. Theology is a rational study of the existence of God/gods and the nature of religious ideas. 2. Theology is simply a study of a particular religion (or all religions), really more the practice than the theory, but maybe a mixture.  It seems from an immediate reading that definition 1 would lead to the conclusion that a theologian is a philosopher (perhaps that theology is a branch or subset of philosophy), but definition 2 appears to be rather unphilosophical in nature.    So, how does philosophy answer this question?   Is theology considered a proper subset/branch of philosophy overall? Does it depend entirely on which of the above 2 definitions of theology fits a particular theologian as to whether he is a philosopher or not?   I think this answer is simple and fairly self-evident, but somewhere in my gut I feel like I'm missing something.  Is there a treatment of this question in the literature?    Edit: the answers so far seem to want to redefine theology or other terms - that is fine, but please be clear that you are redfining them, and provide, if possible, sources for why the term should be different than given (support from historical works, other sites, etc.). What is the spell save DC and spellcasting modifier for a Rogue with Magic Initiate? As a rogue I'm planning to take Magic Initiate with warlock class. The Magic Initiate feat says:     [...] Your spellcasting ability for these spells depends on the class you   chose: Charisma for warlock [...]    cantrip 1: Booming blade or Green flame blade cantrip 2: Minor illusion 1st-level spell: Hex    My stats bonuses are: STR : -3 | DEX +6 | INT 0 | WIS +1 | CHA +4 | prof : 4  Questions:   Green flame blade :      [...] The second creature takes fire damage equal to your spellcasting   modifier. [...]   What is my spellcasting modifier? 0 from INT as rogue or +4 from CHA as warlock?   Minor illusion :      [...] If a creature uses its action to examine the sound or image, the   creature can determine that it is an illusion with a successful   Intelligence (Investigation) check against your spell save DC. [...]   What is my spell save DC? 12 (8 + 0 from INT + 4 from prof) or 16 (8 + 4 from CHA + 4 from prof)? Can $X$ have compact connected components? Let $X$ be a Hausdorff, locally compact but non-compact topological space. If the (Alexandroff) one-point compactification is connected, can $X$ have compact connected components? Why do backslashes appear twice? Unitary map between sets of vectors Whenever Ubuntu boots up, a dialogue pops up asking me to unlock my default keyring. Is there some way this can unlock automatically through PAM or some other magical way? Strictly diagonally dominant matrices are non singular How does the integral $\int_{D_C} e^{ia z}P(z)/Q(z)\,\mathrm{d}z$ blow up. In my book I have a theorem that goes something like the following     Let $P(x)$ be $Q(x)$ polynomials such that $\deg(Q) \geq \deg(P) + 2$.   Then \begin{align*}  \int_{-\infty}^{\infty} \frac{P(x)}{Q(x)}  e^{iax} \,\mathrm{d}x  = 2 \pi i \frac{a}{|a|} \sum_{k=1}^{m} \mathrm{Res}\left[  \frac{P(x)}{Q(x)} , z_k \right] \end{align*} where $a$ is a real   constant and $z_1,\,\ldots\,,z_m$ are the singularities to $P(x)/Q(x)$ in   the upper halfplane if $a&gt;0$ and the lower halfplane if $a&lt;0$.   I am having a bit of problems understanding this. I know the reason why we have to switch contour is that $e^{iz}$ blows up. But I really can not see why or how it blows up.   Take the canonical example for why this theorem is useful  $$   J = \int_{-\infty}^\infty \frac{e^{iz}}{z^2+1} $$    Now the clue here is to show that the integral along the curve tends to zero, and then use the residue theorem. To show that the integral tends to zero I did this \begin{align*}  \left| \int_{C_1} \frac{e^{iz}}{1+z^2} \,\mathrm{d}z\right|  \leq \int_{C_1} \left| \frac{e^{iz}}{1+z^2} \right| \,\mathrm{d}z   \leq \sup_{z = R e^{i \theta}} \left( \frac{1}{\left|1+z^2\right|} \right)       \int_{C_1} |e^{iz}| \,\mathrm{d}z \end{align*} where the $ML$-inequality was used in the last inequality  On the circle with radius $R$ we have $|e^{iz}|=R$, and we can use the inequality $|a+b|\leq|a|-|b|$ to simplify further \begin{align*}  \left|\int_{D_R} \frac{e^{iz}}{1+z^2}\,\mathrm{d}z \right|  \leq \sup_{z = R e^{i \theta}} \left( \frac{1}{|z|^2-1}\right)  \int_{D_R} R \,\mathrm{d}z  \leq \pi \frac{R}{R^2-1} \end{align*} which tends to zero as $R \to \infty$ as wanted. but if one instead had $e^{-iz}$ then the theorem states that one has to use the lower half plane. But I do not see where my calculations err if one persists in using the contour in the upper half plane? What goes wrong, and why does it go wrong? $|e^{-iz}|$ should still be $R$ on the semi-circle.   How can one formally show that the integral diverges when picking the contour as a semi circle in the lower half plane? I get Chrome notifications from several websites and they work when I don't even have any tabs open for those sites.  But sometimes I get these Chrome notifications when I am not at my desk or looking at my laptop.  As some of these notifications are useful to me, I would like to be able to access any that I have missed.  Is there a way to view the notification history? How to remove URI encoding from file names? I realise this might be quite a simple question, but I'm still quite new to the command line and only have a grasp of basic commands.  I've downloaded some lecture presentations (~25 or so) from my University however on doing so they've been named things like...  L2%20Development%20of%20immune%20system.pptx L4%20Molecular%20Recognition.pdf   As you can see they've downloaded with the URL encoding %20 instead of a space.  My question is how to batch rename all of these files so that the %20 is removed and replaced with a space instead? Should I remove non-significant variables from my regression model I have run a multiple linear regression using stepwise regression to select the best model, however the best model returned has a non-significant variable. When I remove this the AIC value goes up indicating the model without the significant variable is a worse fit. Should I remove the non-significant predictor or should I leave it in as it is a better model? How to iterate over a comma separated list?