I am unable to connect my javafx scene to mysql database. I get a java.lang.NullPointerException every time. I tried searching everywhere possible but no answers available. This is the Person class (super class for Teacher class):
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
[code].....
I do Java for decades, but am a FXML beginner. Currently I do FXMLLoader.load(fxmlFile) in Application.start(), which is working well. My Application instance is creating a background thread in Application.init() which feeds several custom application properties with incoming data taken from a remote model (wrapping a sensor hardware). Some of my windows shall later be able to access those properties. So the question is: How can I inject my Application instance into the FXMLLoader-created controller instances auto-bound to the FXML-created Scene instances?
View Replies View RelatedI used the SceneBuilder to create an applications and it works quite well. Now I got a problem to set the pref. size of a ScrollPane to the size of the app.
I want to install a binding between the scroll pane's pref. size and the stage's pref. size. Since the scroll pane field reside in the FXMLController class I need a way to access this field.
Sometimes models needs to access blocking devices, like network cards, databases, files, and so on. This should be done by worker threads or services. But who is in charge of that? The controller or the model itself? I tend to say it is the model, as only the model knows about the fact that it accesses a blocking object. On the other hand, it is said that a model should be a POJO, so it would be the controller's job. Is there a best practice or general design rule?
View Replies View RelatedI've run in an issue with connection timeout in the WebView. Requesting the URL in a browser will result in an answer, however it may take some time. Running the same request from the WebView results in a connection timeout.
What is the connection timeout for loading a page through the WebView (from issuing the request webEngine.load(url) to the state change failed passes about 40s). The Request in a browser takes about 10s.
Can I manipulate the underlying connection of the WebView (as suggested at java - How to connect to an HTTPS URL from a JavaFX application - Stack Overflow)
Can I set the connection timeout on the WebEngine/WebKit or per request?Is there an issue targeting this?Likewise I would be interested to get a handle on the connection so I can evaluate the header data to retrieve useful information (like response was a PDF which cannot be rendered in the WebView)....
I am new to javafx and my goal is to basically just test if my java code works with Mysql. What I'm planning to do is to display one data of the sakila database into a Label named greetingLabel. And I can't seem to find where i went wrong so i'll show you my whole code.
Here is the main code for my controller class from scene builder:
package main;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Label;
[Code] .....
Here is the error displayed when pressing the button
Exception in thread "JavaFX Application Thread" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at javafx.fxml.FXMLLoader$MethodHandler.invoke(Unknown Source)
at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(Unknown Source)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(Unknown Source)
[Code] .....
I am trying to load a CSS file from a mySql DB table (each row represent a customer that use the application, and each one can set his own CSS file).
How can I convert the Stream / String that I loaded from the Clob column to something that I can use here XXXX
scene().getStylesheets().add( XXXX );
I found alot of examples, but they all talking about files from filesystem, or URLs. My CSS file is in the application memory. I want to prevent the option to write my string as a new file and then read it again. I have no problem with loading the CSS file from database, this part is O.K.
I have created a JSP page, on click of a particular button, the control moves to the servlet "TestServlet".
This is the code under TestServlet:
import java.io.IOException;
import java.io.PrintWriter;
import java.security.Principal;
import java.sql.Connection;
import java.sql.SQLException;
import java.sql.Statement;
[Code]...
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?
View Replies View RelatedModel View Controller design pattern I completely understand then I was told about the observer controller pattern. After reading and reading I and watching video clips on youtube explaining it I have a question:
Isn't the actionListener the observer so to speak. It is firing whatever action it is told to do and dynamically updates the program to.
Example, I have a JButtons and a JTextArea. I press the button and it gives the current stock price of some stock, I press it again it refreshes. Sounds like an observer to me... Am i on the right track here?
create an application following the MVC pattern. My frame is composed of a JTable with some JComboBox and classic next/previous buttons to page the table. The table shows data of current accounts of the members of a family. My problem is figuring out how the controller interacts with the view, for example to enable / disable buttons or reset and reload the data in the comboboxes. In the view class all the graphical components are private instance variables. What is the best approach to ensure that the controller can act on them?
I need to create in the view public methods to act on each component like getSelectedItemAccountCombo, getSelectedItemYearsCombo, getSelectedItemMonthCombo, populateAccountCombo (ArrayList <String> list), setNextButton (boolean b) ... and so on (I think that the methods would be many ...) This approach does not convince me because I think that the class is fouled by procedures that should be in the controller class.
I've got 2 view classes with their own viewcontroller. In view 1 i'v got a combo box with a observablelist wicht show me some values.
What i want is to put an new value to the combobox through the controller of view2.
When i make the observablelist static it works but i think that isn't a nice way.
I have used jsp's to passing request to the servlet or controllers. but we can also pass request from javascript using ajax and sending data using json.
what is the good approach and why? or does it depends on the situations? is yes, what kind of situations?
I am working on an project in which some data needs to be received through socket , do some processing on it and then store on the database. After that it will display on GUI. GUI should be updated automatically.
I am able to implement basic model in which data is storing in the database and displayed then on the GUI. I tried to implement MVC design patter as well.
Now i need to create a GUI which can be used by several users at a time means several jvm session for the GUI. I got struck at this point.
Some detail: i have one jvm session in which i am receiving , processing and storing the data. Now i want to fire an alert whenever any new entry is made into the database. Also each time new GUI is opened it should be registered with the model so that model send updated data alert to all this users.
When i am trying to open several GUI and trying to register with the Model then it is not increasing count of registered user. For each time it is showing 1 count only and whenever a new entry is made count is showing 0. Is it because both are running in different jvm sessions ?
Some code for the model which is running in different package and jvm
GUI..
private void runApp() {
//some gui code
WindowListenerClass windowListener = new WindowListenerClass(this);
frame.addWindowListener(windowListener)
//registering viewer with the model
Model.setNewAlarmEvent(this);
tableModel = windowListener.getDefaultTableModel();
[Code] .....
When I hit the url at the first time my call goes to the spring controller and sets the userDetails objects in the modelAndView.addObject("userDetails", userDetails.getUserDetails()) and returns the userDetails.html page. if I click any link in the same page i want to pass same (userDetails) object thru javascript or jquery and calls the another(controller) method and returns the same (userDetails.html) page.
It means how can I pass the java object thru javascript or jquery and calls the controller. If I get the same object in my controller i can avoid calling the db again.
I need to pass advanced object into controller from JSP page, but I always get null result.It's a controller method:
Java Code:
@RequestMapping(value="admin-user-edit", method=RequestMethod.POST)
public ModelAndView editUser(@ModelAttribute(value="user") UsersEntity user)
{
if (null == user)System.out.println("User is null");
else
System.out.println("User name = " + user.getName() + " | Users id = " + user.getId());
ModelAndView view = new ModelAndView();
return view;
} mh_sh_highlight_all('java');
And this is a JSP page snippet. I need to choose some user from user list and pass it to controller.
XML Code:
<c:forEach var="user" items="${user_list}">
<tr>
<td><c:out value="${user.id}" /></td>
<td><c:out value="${user.name}" /></td>
<td><c:out value="${user.login}" /></td>
<td><c:out value="${user.status}" /></td>
[code]...
I tried to pass it through HttpServletRequest argument but all the same.
I have a controller that on the basis of commands (formaction and subaction) dispatch requests to different jsp pages. But somehow when I am debugging my application, I can find duplicate request coming to the controller, so one jsp page does load twice. I am not sure from where the duplicate request is generating.
View Replies View RelatedI use a bluetooth module (dwengo) in combination with a microcontroller (PIC16F877A). I want write a bluetooth client program in java to communicate with the microcontoller. Examples of clients on internet do not work or give errors I cant'n resolve. There is one program ( SampleSPPClient ) that give no errors and shows the bluetooth devices present.
But when I choose my bluetooth module I got an error (Device does not support Simple SPP Service). I think that I have to use an other service of bluetooth but I don't know how to implement. Here is the program I tried to use ....
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.util.Vector;
import javax.bluetooth.DataElement;
[Code] ......
how to give URL Connection to this?
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.net.*;
import java.io.*;
import javax.swing.*;
import javax.swing.event.*;
public class WebBrowser
[code]....
I was wondering if I could take the following code and somehow put the connection to database in it's own class without the "public static void main(String[] args)" method. That way I could call it anytime i want to open a connection to the database.
Java Code:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class Sample {
public static void main(String[] args) throws ClassNotFoundException
[Code] ....
I am new to EJB; I am writing EJB (3.1) program in JBoss 7.1 - I am using MySQL DB with JPA. While executing the program, I am facing the Generic JDBCException: Could not open connection. It is happening only for certain tables in the database; but NOT for all tables. My code is able to access few of the tables in the same database. Here is my full stack trace: -
Exception in thread "main" javax.ejb.EJBException: javax.persistence.PersistenceException: org.hibernate.exception.GenericJDBCException: Could not open connection
at org.jboss.as.ejb3.tx.CMTTxInterceptor.handleExceptionInOurTx(CMTTxInterceptor.java:166)
at org.jboss.as.ejb3.tx.CMTTxInterceptor.invokeInOurTx(CMTTxInterceptor.java:230)
at org.jboss.as.ejb3.tx.CMTTxInterceptor.required(CMTTxInterceptor.java:304)
at org.jboss.as.ejb3.tx.CMTTxInterceptor.processInvocation(CMTTxInterceptor.java:190)
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288)
[code]....
I'm using oracle 10g Database and Java 'jdk1.7.0_45' version.I have to a create program to insert data into a table.
View Replies View RelatedI'm using JSF framework. I can let Netbeans to create the persistence unit and hardcodes connection parameters into the persistence.xml file or i can use resource tag in context.xml file or using another file like property file or class for holding connection parameters like username and password; what is the most secure way or expert way to use connection properties in my app or there is no difference?
View Replies View Relatedpackage com.dnex;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
[code]....
I am getting the connection time out error in below line :-
System.out.println("response code"+httpConnection.getResponseMessage());
Note:-I need to pass user id and pwd in header parameter.and I am using https connection.
I am trying to make a simple login using netbeans, derby database included in netbeans and tomcat server. I made everything nice and separated: I have a model package with a class called DbConnector that has the following method:
public Connection connect() {
try {
return DriverManager.getConnection(url, user, pass);
} catch (SQLException ex) {
return null;
}
}
Then i have another class, an userDAODB that has a password check method:
public boolean checkPassword(String user, String password) {
try (Connection con = new DbConnector().connect(); Statement stmt = con.createStatement()) {
//checks the password in the database
In the main method of this class i tested everything, it works very nice, logs me in, other methods work too, no problem what so ever.But then i go to my servlet:
public class LoginTest extends HttpServlet {
public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
String username = request.getParameter("username");
String pass = request.getParameter("pass");
UserDAODB userDAO = new UserDAODB();
boolean authe = userDAO.checkPassword(username, pass);
[code]....
So when i start the webpage and i try to click on the login button I get a NullPointerException com.model. UserDAODB. check Password (User DAODB. java:14) - so line 2 here
I have been googling a bit, i placed the derby.jar and the derbyclient.jar in the lib directory of tomcat, i tried to modify the context.xml of my application, but then it wouldn't even start anymore.
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)
[Code] .....