Getting NullPointer Exception In Unit Test At Activemq Connection Factory Creation
Dec 2, 2014
I have the following unit test that gives me a null pointer exception. The debugger goes to the finally block right after the line that creates a connection factory. Here's the test:
I hope I'm putting this question in the right folder. I have an array of objects, and I have defined a setter for a variable in the object. When I call the setter, I get a NullPointerException. Here is the relevant code for the object.
public class Digit extends Thread { private int digit; public void setDigit(int digit) { this.digit = digit; } // run method follows }
Here is the portion of the main class where I define an array and then call the setter.
Digit[] digits = new Digit[10]; for (int i = 0; i < digits.length; i++) { digits[i].setDigit(i); // NullPointerException occurs here }
I am creating a simple ArrayList program that would enable one to input their username to it using a scanner. However, i am getting this error: "Exception in thread "main" java.lang.NullPointerException
at home.Members.addUser(Members.java:16) at home.Main.main(Main.java:14)"
Here is the code! :
Main.java class Java Code: import java.util.Scanner; public class Main {
I have problem with my simple program. I tried put some text in my text area using button1 but textListener in RighButtons is always null and it's give me NullPointerException.
WriteToArea - interface public interface WriteToArea { public void add_a(String text); } BaseFrame public class BaseFrame extends JFrame{
If I put the highlighted text in try/catch block it is throwing NullPointerException , if I am using command line arguments then also it is showing the same exception.
I am getting a nullpointer exception after "cleaning" up my code by putting repetitive stuff in a method.
The error points to this: ai.getItRight(n, answer);//make sure the user enters yes or no..
The error occurs at lines 19 and 25.Here is the relative code:
public boolean AskQuestions(Node n, String yesOrNo, String answer, String question){ if(yesOrNo.equalsIgnoreCase("no") && n.getRight() == null){//i guessed the wrong answer System.out.println("I give up. Who is it: "); answer = input.nextLine();
[code]....
My previous code, which use to have the contents of getItRight in place of lines 19 and 25 worked just fine. So why am I getting this error? I dont want my methods to be crazy big like how they usually end up.
I've got a nasty nullpointer that I have tried to resolve to no avail as of yet. The program should prompt for a listings.txt file and take its info and write to a report file. Here's the stacktrace:
run:
Input file: listings Exception in thread "main" java.lang.NullPointerException at java.io.Writer.<init>(Writer.java:88) at java.io.PrintWriter.<init>(PrintWriter.java:113) at java.io.PrintWriter.<init>(PrintWriter.java:100) at kettask2b.PropertyListingsReport.main(PropertyListingsReport.java:34) Java Result: 1
Some adjustments that I have attempted are:
BufferedWriter pwfo = null; for (int i = 0; i < args.length; i++) { String string = args[i]; pwfo = null;
public Unit(String code, String name) { enrolStudent(student); this.unitCode = code; this.unitName = name; } public void enrolStudent(Student newStudent){ students = new ArrayList<Student>(); newStudent = new Student(24662496, "Kingsley", " Iwunze"); students.add(newStudent); }
how can I call this enrolStudent() method on this Unit constructor in another class when I create a new Unit. all I need is to enroll students in units when units are created. below is my create unit method.
I got the below exception .how to resolve this .It's receiving the data up to 10 min then suddenly below error happening. I have embedded the source code below
java.net.SocketException: Connection reset at java.net.SocketInputStream.read(Unknown Source) at java.net.SocketInputStream.read(Unknown Source) at sun.nio.cs.StreamDecoder.readBytes(Unknown Source) at sun.nio.cs.StreamDecoder.implRead(Unknown Source)
Below is a code of a simple file downloader in java. I want to detect an exception when the connection is broken in the middle of downloading a file. Now, I run the code and in the middle of downloading the file, i turn off my wifi with keyboard wifi off button. Doing this the program hangs forever without throwing any exceptions and without terminating. It seems it blocks forever.why is exception not thrown? Secondly, in the following code you can see this line //con.setReadTimeout(2000); which is currently commented out. Removing the comment and running the program, now if connection breaks in the middle by turning off wifi then it waits for 2 seconds and then if it cannot read then it terminates without throwing exception. So, again in this case why is it just terminating and not throwing any exception?
The test exits and if I look at the ActiveMQ admin console, it now shows two messages enqueued, 0 dequeued This seems ok
Finally i run the consumer test again. It receives the messages just fine. But again the ActiveMQ admin console shows two messages enqueued and , 0 dequeued. It always shows 0 dequeued.
I even changed the test so that instead of doing a sync receive it used an async receive with a listener...but still the same behavior. The topic dequeued value is always 0 on the Topics base of the ActiveMQ web console.
I am using ActiveMq alongwith Spring in my project. I want my queue to be configured to reject the duplicate messages.I tried my level best to do so. I tried googling for the same. but could not get anything.
Now, I have got a comment saying I should get the database connection from connection pool. And one more issue is that I have used the function System.getProperty("user.name") to get the username which i have logged in. But this code will be run on Unix which will not support this function. Any function where I can get the windows username. There is a function getUserPrincipal(), but this function returns a NULL. How to resolve this.
I configured a connection pool in tomcat 7. For every database activity I get a connection from the pool. Do I have to close the connection like other regular connection after the database operation is done? If I close the connection will it have any effect on the connection pool?
My assignment was to create a simple form that demonstrates the use of the factory and singleton design patterns. "Use the Factory pattern to ensure that each form input consists of a text label and a textfield. Use the Singleton pattern for the submit button. When the submit button is clicked, a pop-up should show all the information that was typed into all of the form fields."
I used JFrame to create the form without the design patterns and I although I get the desired result, I'm not quite sure how I can integrate the design patterns into the code I wrote. The example I have to go off uses shapes, not text fields so I think that's why I'm not quite clear on how to approach this.
My assignment was to create a simple form that demonstrates the use of the factory and singleton design patterns. "Use the Factory pattern to ensure that each form input consists of a text label and a textfield. Use the Singleton pattern for the submit button."
Here's what I have:
Form.java file
interface Form { public void getFormField (); } Name.java file (I have a similar files just like this for Address.java, City.java, State.java, Zip.java and Phone.java) import java.util.Scanner; class Name implements Form
[Code] ....
It compiles at the moment but I get a null pointer exception in the main method of the FormFactoryDemo file.
In my application, users select the year and manage data for that year (for example, they can choose 2014 for managing invoices for 2014, then switch to 2015 and work with that year). Each year as his own database.
I'am able to change persistence unit connection at runtime with Persistence.createEntityManagerFactory(PU_NAME,map_with_connection_info) This procedure build a non-jta environment.
It is possible to create entityManager / entityManagerFactory with JTA ?
I don't want to create new persistence unit each year or each time a new database is required.
So I have this 2D array that contains some Object foo.
[f] [f] [f][f]
[3][3][3][3]
[b][b][b][b]
[x][x][x][x]
[ ][ ][ ][ ]
[ ][ ][ ][ ]
[ ][ ][ ][ ]
I want to shift all the rows down one unit, starting for the rows containing x. So the x row is first shifted to row 4. then the b row shifted to where the x row was, row 3 and so on. My question is:
1. How can I check if the next row is empty
2. How do I shift a row down
Here's my attempt:
Java Code:
//board is the 2D array defined elsewhere public void shiftRowDown(){ int counter = 0; int rowCounter = 0; for (int i = 0; i < this.board.length; i++) {
I am having a difficult time trying to get results from the code below. The purpose is for my program to insert the DHL tracking number in the tracking text box, and then for the program to "click" the search button and get the tracking results.
This is the code:
import com.gargoylesoftware.htmlunit.WebClient; import java.io.*; import com.gargoylesoftware.htmlunit.html.HtmlPage; import com.gargoylesoftware.htmlunit.html.HtmlInput; import com.gargoylesoftware.htmlunit.html.HtmlSubmitInput; import java.net.*; public class DHL {
[Code]...
These are the results I am getting in the console (in red), which look like an error:
Apr 23, 2015 7:55:49 PM com.gargoylesoftware.htmlunit.javascript.host.html.HTMLElement addbehavior WARNING: Unimplemented behavior: #default#userdata Exception in thread "main" com.gargoylesoftware.htmlunit.ElementNotFoundException: elementName=[*] attributeName=[name] attributeValue=[sbtc] at com.gargoylesoftware.htmlunit.html.HtmlPage.getElementByName(HtmlPage.java:1747) at htmlTest.main(htmlTest.java:17)
I just cannot figure it out for the life of me. Also, is there a community that focuses on HTML Unit?
I have a bean that represents data been collected from a form on a jsp page. Currently I would like to validate my fields and write some test cases for them. As you can see from my test case example I test a string in the hope that it fails because it contains only one letter. My problem is my unit test is passing. The reason this is from what I can tell is that at runtime it fails when I try to persist my object using my entity manager. During my unit test I just I don’t call my entity manager I just try and set the field.
What I thought would happen was that when I use my bean fields set method the annotations would be checked and fail at that point. Hence why I expected my unit test in this case to fail.
What I would like to know is
1.Are annotations specifically designed to validate when I persist my object and am I using them incorrectly at this point?
2.Is this the best method to use to validate fields, is there a better way, should I write my own code to validate for me when I set my value?
a. Should I throw an exception from the set method of each bean field?
Unit Test:
@Test public void testName(){ Human h=new Human(); try { h.setFname("a"); } catch (Exception e) { // TODO Auto-generated catch block fail("failed"); e.printStackTrace();
So, here is the question I have been working on: Write a java class named Time that prompts the user to input the elapsed time for an event in seconds. The program then outputs the elapsed time in hours, minutes, and seconds. (For example the elapsed time is 9630 seconds, and then the output is 2:40:30 ).Hint: an hour has 3600 seconds and a minute has 60 seconds. Use Scanner class for reading the input.
Here is my code:
import java.util.Scanner; public class Time { public static void main(String[] args) { Scanner scan= new Scanner(System.in); System.out.println("Enter the elapsed time in seconds:"); int totalseconds= scan.nextInt();
[Code] .....
Now, I know I am supposed to use the remainder operator to figure out the time in minutes and seconds, but the hours has be a little confused. Right now this code compiles but gives me an exception.
One of the four JDialog class would look something like this without the comments.
package client; import javax.swing.JDialog; @SuppressWarnings("serial") public class AddCustomerDialog extends JDialog implements Dialog{ public AddCustomerDialog () { //Some stuff goes here to set the settings for JDialog instance
When creating VRML, there is a convention that one unit corresponds to 1 metre in the real world. This makes sharing models easier. Is there any similar convention for JavaFX 3D?
I have two classes Person and Group. Group object is suppose to contain many Persons, How can I write unit tests when some other classes are involved and abstraction is much higher?
