I am looking for a way to make a button change from saying "Player 1 End Turn" to "Player 2 End Turn" when pressed. The following is what I have:  private int pTurn = 1;         Button turn = new Button();             turn.setText("Player " + pTurn + " End Turn");             turn.setOnAction(new turnButton());  //There is code between these two blocks, but it isn't important for //this question I don't think          class turnButton implements EventHandler&lt;ActionEvent&gt; {         @Override         public void handle(ActionEvent event) {             pTurn++;             if (pTurn == 3) {                 pTurn = 1;             }             turn.setText("Player " + pTurn + " End Turn");         }      }   When I run this and press the button I get the following error:  Executing /Users/bronsonlane/NetBeansProjects/FinalProject/dist/run1715909217/FinalProject.jar using platform /Library/Java/JavaVirtualMachines/jdk1.8.0_111.jdk/Contents/Home/jre/bin/java Exception in thread "JavaFX Application Thread" java.lang.NullPointerException at halma.Halma$turnButton.handle(Halma.java:234) at halma.Halma$turnButton.handle(Halma.java:227) at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86) at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?
Extracting raster values at points using Open Source GIS? Can I use two 7805 ICs in parallel to get double current capacity? I use a 7805 for a project where the circuit needs a higher current (~2.8&nbsp;A) at 5&nbsp;V. So I assume that if I use both ICs in parallel I can increase the maximum current capacity. Would it work? How to avoid using sudo when working in /var/www? Can we get an indication comments are hidden between the comments? I'm trying to make a systemd timer that runs every 15 minutes. Right now I have:     timer-fifteen.timer:  [Unit] Description=15min timer  [Timer] OnBootSec=0min OnCalendar=*:*:0,15,30,45 Unit=timer-fifteen.target  [Install] WantedBy=basic.target    timer-fifteen.target:  [Unit] Description=15min Timer Target StopWhenUnneeded=yes    This runs over and over again without stopping. Does it need to be *:0,15,30,45:* instead? How can I make this work? Scenario 1: A grimlock hits Alice with a Spiked Bone Club, dealing 5 bludgeoning damage, plus 2 piercing damage. Alice's HP was 12.   Using the optional Massive Damage rules on page 273 of the DMG, does this count as more than half the HP from a single source, or less than half, but twice?  Scenario 2: Assume the same grimlock hits Bob with the same attack, this time rolling 6 bludgeoning damage, plus 3 piercing damage. Bob's Max HP is 8, and he had 1 HP remaining before he was hit.  Using the Instant Death rules on page 197 of the PHB, does the character die, or are the two damage types tracked separately? Does the character have to make a death saving throw for the second part of the damage? How to see what's going on during Windows shutdown/logging off process? Windows 7 msconfig lets users select the options No GUI boot and OS boot information to have a list of drivers being loaded during boot. Is it possible to have similar detailed messages during shutting down/restarting/logging off? Here's the screen I want disable or give me more details: How to get product recommendations Possible Duplicate:          I have a question of the form "what companies provide service X?"  I checked meta, and apparently such questions are highly discouraged on all Stack Exchange sites. Which is fine, but it obviously raises the meta-question: Where can I ask my question?  (In particular, I know that there are people hanging out on Stack Overflow who have probably needed the same service, so if an answer exists, they possess it...)  Edit: I should perhaps point out that the service I'm looking for is rather specific and slightly obscure. Otherwise, yeah, this would be a 10-second exercise with Google. Badge Notification Repeats Not sure if someone else has already raised this - I've got eleven notifications that I've received a Caucus badge on English Language Learners. Perhaps one notification for each community that I'm a member of?  I am a member of the community, and did visit the election. Also, the badge hasn't been awarded more that once (so I think it's just the notification that's at fault).  Note that this seems to happen for other badges, it has been reported for: Caucus, Nice Answer, Enthusiast. Is there way to enable more than 4 GB RAM in 32-bit Windows OS? I upgraded my PC to 4 GB RAM and I get only 3 GB. Windows 7 32-Bit consider that I've 4 GB RAM but didn't use more than 3 GB.  Someone told me that MS Windows 32-bit doesn't support RAM larger than 3 GB.  So please is there any way to make my OS "Windows 7 32-Bit" support more than 3 GB RAM ?  *`Note: I can't move to 64-bit because I've many program doesn't work with a 64-bit OS.  Edit::  I tried what Mr. Wonsungi advised me but whenever I check this option:      Enable support for 4 GB of RAM   I get the following error:      'Cannot access to the registry key   HKEY_CLASSES_ROOT\CLSID\{E88DCCE0-11d1-A9F0-00AA0060FA31}.'   There is no "CLSID" in my registry, I don't know why!. I have come across the following few questions on past exams papers.. I know how to solve these type when it is of the form $a_nz^n$ but don't have a clue what to do with these. Any help would be greatly appreciated!  (i) $\displaystyle\sum_{n=0}^\infty \bigg(\dfrac{1}{2n}\bigg)z^{3n}$.  (ii) $\displaystyle\sum_{n=0}^\infty(2^n+i)(z-i)^n$.  (iii) Show that the radius of convergence of $\displaystyle\sum_{n=0}^\infty z^{n!}$ is $1$ and that there are infinitely many $z \in \mathbb{C}$ with $|z|=1$ for which the series diverges. Probability of first actor winning a "first to roll seven with two dice" contest? Getting all the combinations in an array How do I make a Villager Trade a Spawn Egg I am trying to make a Custom Trade on a villager. I need to make him buy 8 gold nuggets and sell a Cow Spawn Egg.  basically you pay 8 nuggets for a Cow Spawner.  The ID of the Cow Spawn Egg is 92 but I don't know where to put it in the command /summon Villager ~ ~2 ~ {Invulnerable:1,CustomName:Spawner_Vendor,Profession:2,Career:1,Offers:{Recipes:[{buy:{id:gold_nugget,Count:8},sell:{id:spawn_egg,Count:1}}]}} I recently upgraded my CPU from an Athlon II X2 250 to the Athlon II X4 610E(45W 4 cores -- can't beat the efficiency).  Is an ubuntu reinstall required? RegEx: Grabbing values between quotation marks I have a value like this:  "Foo Bar" "Another Value" something else   What regex will return the values enclosed in the quotation marks (e.g. Foo Bar and Another Value)? \mathbb{Z} yields undefined control sequence error "Try and" versus "Try to"? Comparing areas in scanned historical land use maps using QGIS? Does $\lim_{n\to\infty}\underset{n}{\underbrace{\cos(\cos(...\cos x))}}$ exist? Possible Duplicate:         Does the following limit exist?  $$\lim_{n\to\infty}\underset{n}{\underbrace{\cos(\cos(...\cos x))}}$$  If yes, find the limit.  If no, please explain why the limit doesn't exist.  I think, the limit exists.  So, I tried to use Squeeze theorem but didn't work.