I have a directory structure for a web java application + standalone application like this: src/logic/view/desktop src/logic/view/web and src/logic/bean,control etc... In src/logic/view/web i have my web application with WEB_INF, META_INF, mypage.jsp etc... mypage.jsp  &lt;%@ page language=&quot;java&quot; contentType=&quot;text/html; charset=ISO-8859-1&quot;     pageEncoding=&quot;ISO-8859-1&quot;%&gt;    &lt;!-- dichiarazione e instanziazione di un BeanAddReport !--&gt; &lt;jsp:useBean id=&quot;addReportBean&quot; scope=&quot;request&quot; class=&quot;logic.bean.AddReportBean&quot;/&gt;  &lt;!DOCTYPE html&gt; &lt;html lang=&quot;en&quot;&gt; &lt;head&gt;     &lt;meta charset=&quot;ISO-8859-1&quot;&gt;     &lt;title&gt;Add Report&lt;/title&gt;          &lt;link rel=&quot;stylesheet&quot; href=&quot;css/mycss.css&quot;&gt;  &lt;/head&gt; &lt;body&gt;          &lt;img class=&quot;backImg&quot; alt=&quot;&quot; src=&quot;&lt;%=request.getContextPath()%&gt;/img/backgroundImage2.jpg&quot; width=&quot;1366&quot;&gt;          &lt;/body&gt; &lt;/html&gt;   and the bean class package logic.bean;  import logic.controlgrafico.AddReportGuiControl;  public class AddReportBean {      private String queueLen;     private boolean isLast;     private Object gui;     private String attractionName;          public void setQueueLen(String s) {         queueLen = s;     }          public void setIsLast(boolean b) {         isLast = b;     }          public void setGui(Object gui) {         this.gui = gui;     }          public void setAttraction(String a) {         attractionName = a;     }          public String getAttraction() {         return attractionName;     }          public String getQueueLen() {         return queueLen;     }          public boolean getIsLast() {         return isLast;     }          public Object getGui() {         return gui;     } }   Now my problem is: when I start the tomcat server I receive a org.apache.jasper.JasperException: /addReport.jsp (line: [5], column: [0]) The value for the useBean class attribute [logic.bean.AddReportBean] is invalid.  I think the problem is the project structure and I would tell if there are some configurations, for example in web.xml, that can resolve my problem. I try to run another dummy project with a different directory structure: DummyProject/src/bean.java DummyProject/web/index.jsp where the index.jsp use &quot;useBean&quot; in the same way and all works fine. Suggest me more detail of how the target class works in useBean tag. Ty so much Edit: The difference between the two projects is in C:\Users\simon\eclipse-workspace.metadata.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps The project where all works fine had the path WEB-INF/classes/logic/bean/AddReportBean.class Why the other project doesn't have this path?
I want to use a Java file SaveProp which is written in a package user. The class file has been placed in WEBINF/classes. Below are the two lines which cause the issue.  jsp:useBean id="user" class="user.SaveProp" scope="session"  jsp:setProperty name="user" property="*"   It throws:  The value for the useBean class attribute user.SaveProp is invalid   I'm using Tomcat 6.0.
How to remove configuration files completely Recently I uninstalled some software using sudo apt-get --purge autoremove, thinking that this would remove all traces of it including unused dependencies and configuration files. However I discovered that a configuration file was left behind in my home folder.  Is there a more powerful command which would remove even that?   Also, is it safe to delete the hidden files and folders under home, if they are merely configuration files, or are there other kinds of files? Python dateutils print recurrence rule according to iCalendar format (see RFC 5545) What is the difference between a game framework and a game engine? What is the difference between a game framework (for example, XNA with C#, SDL for c++) and a game engine?  Do game frameworks use engines? Does a game engine encapsulate sub-engines like physics engines, particle engines etc? Should they be used together, or are they mutually exclusively?  I take it there are separate engines for both 2D and 3D? How to install the previous version of a .deb package and pin it? I am trying to install the latest version of subversion on Sid, and because it has a bug I receive a warning and I abort the installation. How do I get to locate the previous version version, install it and pin until the bug is resolved?  root@server01:~# apt-get install subversion   Reading package lists... Done                                                                                                                                                                                  Building dependency tree                                                                                                                                                                                       Reading state information... Done                                                                                                                                                                              Suggested packages:                                                                                                                                                                                              db5.3-util subversion-tools                                                                                                                                                                                  The following NEW packages will be installed:                                                                                                                                                                    subversion                                                                                                                                                                                                   0 upgraded, 1 newly installed, 0 to remove and 205 not upgraded.                                                                                                                                               Need to get 0 B/981 kB of archives.                                                                                                                                                                            After this operation, 4,844 kB of additional disk space will be used.                                                                                                                                          Retrieving bug reports... Done                                                                                                                                                                                 Parsing Found/Fixed information... Done                                                                                                                                                                        critical bugs of subversion (-&gt; 1.9.2-2) &lt;Outstanding&gt;                                                                                                                                                          b1 - #803725 - subversion: dump-load of a repository modifies verbose log output: M line lost serious bugs of subversion (-&gt; 1.9.2-2) &lt;Outstanding&gt;  b2 - #803589 - FTBFS with ruby2.2 (only) Summary:  subversion(2 bugs) Are you sure you want to install/upgrade the above packages? [Y/n/?/...] n ********************************************************************** ****** Exiting with an error in order to stop the installation. ****** ********************************************************************** E: Sub-process /usr/sbin/apt-listbugs apt returned an error code (10) E: Failure running script /usr/sbin/apt-listbugs apt If an element has a unique right inverse, is it invertible? What is the minimum RAM required for Pokemon GO? While poking around on Pokemon Go's , it lists some specs required for Android and iOS devices. I'm particularly interested in Android devices, but I do not see a minimum/recommended RAM listed on their site.        Android 4.4 to Android 6.0.1  (Android N will not supported until the   official Android release)    Preferred resolution of 720x1280 pixels   (Not optimized for tablet)    Strong internet connection (Wi-Fi, 3G, or   4G)    GPS and Location Services    Intel CPUs are not supported      My device is a , which has a 1.5GB RAM and Quad-Core processor. It runs fine for the most part, but a majority of the features heavily lags and are sluggish while I've seen the same features run smooth on other devices.  What is the minimum/recommended RAM for Pokemon Go to run more smoothly? I am stuck on the following problem that says:       a) Find a weak formulation for the partial differential equation $${\partial u\over\partial t\ }+ c{\partial u \over \partial x\ }=0$$    b) Show that $u=f(x-ct)$ is a generalized solution of $${\partial u\over\partial t\ }+ c{\partial u \over \partial x\ }=0$$ for any distribution $f$    My Attempt:   I know that in order to find a weak form of a pde, we need to multiply it by a test function, then integrate it. Also, to find a generalized solution, we need to find a weak solution and just multiply it by the Heaviside function.  Let's take any test function $\phi $, then we have (integrating by parts second part of the integral) $$\int_{\Omega } ( {\partial u\over\partial t\ }+ c{\partial u \over \partial x\ })*\phi(x) dx= \int_{\Omega } {\partial u\over \partial t}\phi(x) dx - c\int_{\Omega } u(x,t)\phi'(x)dx$$ where $\phi $ vanishes at boundaries. So, is it the final form or can we proceed further? And how am I supposed to find a generalized solution?  Can someone help me out? Thanks in advance for your time. How can I check which DNS server am I using (in Linux)? I am using network manager and a wired connection to my university's LAN. (I am trying to find out why my domain doesn't get resolved) Why shouldn't I mix tabs and spaces? If $E[X|Y]=Y$ almost surely and $E[Y|X]=X$ almost surely then $X=Y$ almost surely Identification of particles and anti-particles The identification of an electron as a particle and the positron as an antiparticle is a matter of convention. We see lots of electrons around us so they become the normal particle and the rare and unusual positrons become the .  My question is, when you have made the choice of the electron and positron as particle and anti-particle does this automatically identify every other particle (every other fermion?) as normal or anti?  For example the proton is a particle, or rather the quarks inside are. By considering the interactions of an electron with a quark inside a proton can we find something, e.g. a conserved quantity, that naturally identifies that quark as a particle rather than an antiparticle? Or do we also just have to extend our convention so say that a proton is a particle rather than an antiparticle? To complete the family I guess the same question would apply to the neutrinos. LED accent light that slowly dims when removed from power source We've all played with different transformers and power supplies that have an LED indicator that dims before going out entirely when the power supply is unplugged.  I'm working on designing an accent light which would involve a translucent crystal light source (probably made of resin or glass if I can find a cheap supplier) containing LEDs and certain electronics, and a base which would supply electrical current. For gamers, it might appear somewhat like a Welkynd Stone. My question is what is the simplest way to cause the LEDs to dim slowly (say over 2-10 seconds) when the crystal is removed from the base? Similar to the unplugged transformer, but with an intentional and controlled dimming.  I just purchased some LEDs and plan to build a test system over the next month or two. These LEDs are in a 5 meter strip divided into 3 LED series run in parallel and rated at 12v. I do not know the amp rating of the LEDs, but I'm guessing in the 20ma range (what I've read is average for bright white). I will probably use 4 series totaling 12 LEDs in the test build.   If I have the transformer from AC power built into the base, I was guessing I could use a number of capacitors in parallel with a resistor to store electricity and slowly discharge it into the LEDs. But I'm a self-taught enthusiast so I honestly don't know if this would actually work. Nor do I know the number and ratings of capacitors and resitor that I would need.  If I have the transformer built into the crystal, the transformer and rectifier would retain a small amount of electricity, but I don't think it would be nearly enough to provide the effect I'm looking for, so something else would have to be added to make it last for several seconds.  A nicad battery with control electronics is literally my last resort for achieving this effect, and I'll probably give up on the idea before I go programming my own circuit board.  That's my main question. If anyone wants to toss in some thoughts on how to connect the crystal to the base, I'm open to suggestions. My original plan was to simply have a direct copper to copper connection with the base. But I've recently been considering an EM charging system (akin to a powermat or  my dad has). The concern with the wireless is providing consistent power to the LEDs, though it is safer. I've also learned quite a bit already about constructing the power supply from perusing this SE site, but if anyone has any suggestions for that, too, I'm all ears. For the test build I'll probably hook it up to a computer power supply, or a laptop power supply if I can find a 12v one at Goodwill or the local electronics parts store.  If I get the test model to work, I plan on building possibly a dozen of these for accent lighting around my home. Are the rules regarding absolute modifiers too absolute? The propagation of electric field UK Visa Refusal: Provenance of funds/parking $$\lim _{x\rightarrow 5}\frac{x^2-25}{x-5}  = \lim_{x\rightarrow 5} (x+5)$$  I understand that to evaluate a limit that has a zero ("hole") in the denominator we have to factor and cancel terms, and that the original limit is equal to the new and simplified limit. I understand how to do this procedurally, but I'd like to know why this works. I've only been told the methodology of expanding the $x^2-25$ into $(x-5)(x+5)$, but I don't just want to understand the methodology which my teacher tells me to "just memorize", I really want to know what's going on. I've read about factoring in abstract algebra, and about irreducible polynomials (just an example...), and I'd like to get a bigger picture of the abstract algebra in order to see why we factor the limit and why the simplified is equal to the original if it's missing the $(x-5)$, which has been cancelled. I don't want to just memorize things, I would really like to understand, but I've been told that this is "just how we do it" and that I should "practice to just memorize the procedure." I really want to understand this in abstract algebra terms, please elaborate. Thank you very much. Getting Error while starting Google Map v2 What *is* an Artificial Neural Network? Why didn't Star Trek TOS have better medical equipment for Vulcans? In  when Ambassador Sarek became critically ill, why didn't they send him home or send for a Vulcan medical expert? Since they were hosting many prominent political figures from many races, it seems strange that they did not have much medical support for a race so common as Vulcans (who are part of the Federation). Is it possible to only allow specific packages updates from a PPA Let us say I have added a PPA that has X package that I want but it also has Y package that I do not want to use or receive updates from. How can I, from the same PPA, receive updates for a specific package but deny updates from the same PPA for other packages.  A step by step example would be good since this has happened to me in several PPAs that have a particular package I want but also add a whole bunch of others that I do not yet want to update.