java.lang.NoClassDefFoundError: Could not initialize class me.gacl.util.JdbcUtils
What is a NullPointerException, and how do I fix it?
Print  only? How do I print the indicated div (without manually disabling all other content on the page)?  I want to avoid a new preview dialog, so creating a new window with this content is not useful.  The page contains a couple of tables, one of them contains the div I want to print - the table is styled with visual styles for the web, that should not show in print. Equals(=) vs. LIKE When using SQL, are there any benefits of using = in a WHERE clause instead of LIKE?  Without any special operators, LIKE and = are the same, right? What settings should I be using to shoot "Supermoon"? Solving equation involving Euler's totient function Given $m\in\mathbb{N}$, is there a general way to solve the equation \begin{equation} \varphi(n)=m \end{equation} where $\varphi$ is the Euler's totient function? For example, I want to solve for all the $n$'s such that $\varphi(n)=4$. Is there any way to solve it that are also applicable to many (if not general) cases? Drush PHP syntax error when running I am following the instructions to install Drush that are listed on this page:   I seem to be getting a syntax error within the code:  [user@localhost ~]$ wget https://github.com/drush-ops/drush/releases/download/8.0.0-rc4/drush.phar --2015-11-16 16:23:02--  https://github.com/drush-ops/drush/releases/download/8.0.0-rc4/drush.phar Resolving github.com (github.com)... 192.30.252.131 Connecting to github.com (github.com)|192.30.252.131|:443... connected. HTTP request sent, awaiting response... 302 Found 2015-11-16 16:23:05 (1.47 MB/s) - drush.phar saved [3496991/3496991]  [user@localhost ~]$ php drush.phar core-status  Parse error: syntax error, unexpected '[' in phar:///home/user/drush.phar/includes/output.inc on line 188   I am not seeing this error on Google. Any idea how to fix it? Fundamental Theorem of Calculus. Fundamental Theorem of Calculus says  Let $f$ be an integrable function on $[a,b].$ For $x$ in $[a,b],$  let $F(x)=\int_{a}^{x}f(t)dt.$ Then $F$ is continuous on $[a,b].$ If $f$ is continuous at $x_{0}$ in $(a,b),$ then $F$ is differentiable at $x_{0}$ and $F^{'}(x_{0})=f(x_{0}).$  Now my question is why we are saying that this is "Fundamental Theorem of whole Calculus".  It is clear that it connects intergal and differential calculus. But i am not getting the exact concept, why this is so important as its name is fundamental theorem of calculus. Why we says that it is fundamental theorem of calculus?  Please suggest me. Thanks in advance. We work heavily with serialization and having to specify Serializable tag on every object we use is kind of a burden. Especially when it's a 3rd-party class that we can't really change.  The question is: since Serializable is an empty interface and Java provides robust serialization once you add  implements Serializable - why didn't they make everything serializable and that's it?    What am I missing? How to stop the find command after second match? How to make find command, that will show only first two matches and then end, something similiar to  just version for two records. Seeking Postcode Shapefiles for UK? Network simplex method, leaving and entering variables Write down the sum of sum of  sum of digits of $4444^{4444}$ Let $A = 4444^{4444}$;  Then sum of digits of $A = B$; Then sum of digits of $B = C$; Then sum of digits of $C = D$;  Find $D$.  What should be the approach here? A 256GB SSD has Windows-10 and 16.04 installed.  BIOS not UEFI.  A charity I work with requires me to use Quickbooks Desktop on Windows.  The plan is to ghost the existing system to a 512GB or larger SSD and create a third bootable Windows 7  partition for performing charity activities.   Is this possible to have a third partition? Is there a good example you have used as a guide? Is triple booting with two Windows partitions different from 2 Linux partitions?   If you have done this before ( with GRUB) please indicate this in your response: lessons-learned are appreciated.  Thank you How to import a module given its name as string? Which is right: "In one of the computers" or "On one of the computers"? Essentially, I wonder that if X is a plural noun, should we use a plural or singular verb in a sentence such as "X are a subject that [verb] ..."? I believe that we should always use the singular verb form there (for example, "Eatable flowers are a subject that comes up ..."). However, I was surprised to find this sentence on the  page:     Eatable flowers are a subject that come up in almost all cooking classes eventually and I am a big fan of them.   as well as this on Google Books:     Tools are a subject that come up at our house from time to time.   I think they are typos, but I would like a double check to be sure. Why are values in Entites obtained directly and sometimes by using getters? For example  Drupal\Core\Entity\Entity::id() returns $this-&gt;id(or NULL) Drupal\Core\Entity\ContentEntityBase::id() returns $this-&gt;id-&gt;value Drupal\Core\Entity\ContentEntityBase::uuid() returns $this-&gt;get('uuid')-&gt;value Drupal\node\Entity\Node::id() returns $this-&gt;get('nid')-&gt;value  Also in some methods there are setValue() and getValue() utilised but sometimes there are just $this-&gt;field-&gt;value. So what is the reason for this inconsistent behavior? From my understanding all the &quot;fields&quot; are TypedData fields hence the setValue() and getValue() methods should be used instead of directly access $this-&gt;field-&gt;value. Besides it's strange because $value is private. How to read over 4k input without new lines on a terminal? So I have a lot of data WITHOUT NEW LINES on the clipboard (it's a large SVG file on one line). I went  $ cat &gt;file.svg   then tried to paste (in Gnome Terminal), but only the first 4kB characters were accepted.  I assume this is a readline feature/limitation.  Is there a way to read from STDIN that would avoid this problem?  EDIT  Test case: Create a demo file. This one will have ~4k "=" symbols followed by "foo bar".  { printf '=%.0s' {1..4095} ; echo "foo bar" ; } &gt; test.in   Copy that into your clipboard  xclip test.in   (if you want to middle-click to insert) or  xclip -selection clipboard test.in   (if you want to use Ctrl-Shift-Insert to past it in)  Then cat &gt;test.out, paste (whichever way). Press Ctrl-D to end the stream. cat test.out - do you see "foo bar"?  On my set-up (Ubuntu 12.04, Gnome Terminal, zsh) when I paste I only see the = and I don't see foo bar. Same when I inspect test.out. Can a magnetic field be induced without an electric field? Because, as far as I know, a time varying electric field induces a magnetic field an vice versa.  But in the case of conductors carrying currennt, it doesn't seem that electric field varies with time, then how is a magnetic field induced? Is propagation of uncertainties linear? I'm in doubt with one thing: let's imagine that we have $n+1$ quantities, $n$ of them being directly measured, and the other one being related to the first $n$ by a function $f : \mathbb{R}^n \to \mathbb{R}$. If the $x_i$ is one of the quantities being directly measured and if $\Delta x_i$ is it's uncertainty, then I've learned that the uncertainty of the quantity $y = f(x_1, \dots x_n)$ is given by:  $$\Delta y=\sum_{i=1}^{n}{\frac{\partial f}{\partial x_i}\Delta x_i}$$  My problem in understanding this is: well, if $f$ is such a function, it's derivative is the linear transformation $df : \mathbb{R}^n \to \mathbb{R}$ given by:  $$df=\sum_{i=1}^{n}\frac{\partial f}{\partial x_i}dx_i$$  Where $dx_i : \mathbb{R}^n \to \mathbb{R}$ is given by $dx_i(a_1 \dots a_n) = a_i$. Hence, what we are saying, is that $\Delta y = df ( \Delta x_1, \dots \Delta x_n)$, in other words, we are saying that the uncertainty of $y$ is given by a linear function of the vector of uncertainties of the quantities $x_i$. Why should that be true? I mean, what's the reasoning behind this? I really didn't get the point, my teacher just gave the equation without justifying or anything like that.  Any help and reference is appreciated. How do I compute the normalisation of $A=k[X,Y]/(Y^3 - X^5)$? I'm trying to solve exercise 4.7 in Reid's UCA:  "Find the normalisation of $A=k[X,Y]/(Y^3 - X^5)$."  I can easily show $A$ is not normal: let $x$ and $y$ denote the images of $X$ and $Y$ in $A$. Thus $y^3 = x^5$. So there exists $t=y/x\in\operatorname{Frac} (A)$ which is a root of the monic polynomial $T^3 - x^2 \in A[T]$. But since $t\notin A$, $A$ is not normal.  However, I don't know how to compute the normalisation of $A$; I have not seen dimension theory developed, so  to a similar question doesn't really help me. Similarly I cannot try and apply something like  to a related question, because in this case the map $k[X,Y]\rightarrow k[t]$ sending $X\mapsto t^3, Y\mapsto t^5$ is injective so the image isn't isomorphic to $A$  UCA never really gives a good explanation on how to actually compute normalisations, so I'd be grateful if anyone could walk me through it.