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{
[Code] .....
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;
[Code] ....
Here's the code:
package kettask2b;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
[Code] ....
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.
public static void main(String []args)
args = null;
args[0] = "test";
System.out.println(args[0]);
In my application, some text should be added to a text area in response to a click on a button. So as an action listener to this class, I made another class which implements the ActionListener.
Inside this class, I have obtained the text which I want to be added to the text area. But the text area is in another class and for the action listener I wrote another class.
Now the problem is that when I try to add the text to the text area by the following line of code, it says that textArea_1 can not be resolved or is not a field.
Java Code:
ParentPanel.textArea_1.setText("Name:"+ncrarray[0]+"
Code:"+ncrarray[1]+"
Rank:"+ncrarray[2]); mh_sh_highlight_all('java'); What should I do about it?
Even if I try to write a method like the following in the class in which the text area is created, it gives the same error.
Java Code:
public void printTextArea(String text) {
textArea_1.setText(text);
} mh_sh_highlight_all('java');
The text area is present inside a constructor of the class. I am writing the method outside the constructor (ofcourse).
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 {
[code]....
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:
@Test
public void receiveMessage() throws Exception {
MessageConsumer consumer = null;
ConnectionFactory connectionFactory = null;
Connection connection = null;
Session session = null;
Destination destination = null;
[code]....
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.
This is the code that I wrote but I have two problem with two buttons one of them ... I want to delete the selected text inside the text Area which represented as b[8] and the other button that I want to select parts of the texts which represented as b[0]....
Here is the code..
package KOSAR2;
import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
[Code] .....
I'm supposed to write a GUI application letting the user enter a file on the text field and display its hex representation in a text area and vice versa.
Here's my code:
/*
* 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.
*/
package hexconvertor;
import java.util.*;
import java.io.*;
public class HexConvertor extends javax.swing.JFrame {
[Code] .....
It's not doing anything, I don't understand why.
I am working on a personal project and want to create a text editor to write my code. I am wondering how could I read the last input from the user and if say it was an open curly brace {, then like netbean's my editor will supply the closing curly brace. My java experience is limited but I have tried to read key board input and a few other options that did not work.
View Replies View RelatedI am building a chat server/client and would like to have it so when a user sends a message, the message pops up in the main chat area beside their name, which I would like to be in bold font. Something like "Alan: Hello, how are you?". I can't find a way to do this with a text area or on a string. Do any swing components suitable for use as text areas support bolding of certain sections of the string that you will set to it?
View Replies View RelatedWrite a Java program that calculates the area and volume of a cube, sphere, cylinder, and regular tetrahedron. Your program should obtain the necessary input for each of the objects from the console and output the input, area, and volume of the object. Use appropriate messages to guide the user of your program.
Here what i did, i am not sure if this is what the assignment want, but this is the best method i could come up with
//Khang Le
import java.util.Scanner;
public class InputAreaVolume {
public static void main(String[] args) {
[Code]......
I have a popup that displays textual info and sometimes gets text input from the user. I'm using the following code:
JTextArea textArea = new JTextArea( getGameHistory( true, -2 ) );
JScrollPane scrollPane = new JScrollPane(textArea);
textArea.setLineWrap(true);
textArea.setWrapStyleWord(true);
textArea.setFont(new Font("courier", Font.PLAIN, 12));
scrollPane.setPreferredSize( new Dimension( 30, 100 ) );
String input = JOptionPane.showInputDialog(null, scrollPane, "Fun Chess ",
JOptionPane.YES_NO_OPTION);
This shows a nice text area and an input field underneath it.The getGameHistory() method just returns a long string detailing the current game.Is there a way of just showing the text area without the input field underneath?Can the text area also be used for input instead?
how to put the output the the text area this is the code .
/*
* 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.
*/
package interns;
/**
*
* @author JosephP
*/
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
[Code]...
trying to tranfer content of a text area on one jframe to a text area in another
View Replies View RelatedI have a requirement where in the content of the text area is dynamically populated from the database. I am able to successfully retrieve and display the data on the text area.
However when the content is too large, I am not able to dynamically set the height of the text area. When I try to display the same as a label, the display is flawless, dynamically sets the height as per the content. So, I tried to create a label, with same content and dynamically bind the height to the preferred height as below, but it doesn't work.
// Generate User Note Description
TextArea textArea = new TextArea();
Label text = new Label();
// SETTING THE TEXT TO A LABEL TO RETRIEVE THE HEIGHT
text.setText(usrNotes.getNote().trim());
[Code] ....
How can I read a text file present in my local directory say (C://test.txt) , iterate and populate the values of test.txt into a text area of the JSP page?
Contents in the test.txt file:
username:test
password:test123
domain:test321
DBname:testDB
I have to write a gui program where I can enter a file name and then it gets displayed in a text area when I click Open. Conceptually, I do not get this. I was thinking of appending the text file into a string or something, but I guess I'm confused on how it all works and how I can open the text file. Not asking for the code, but just a compass or something.
View Replies View RelatedI have created a program that allows a pizza shop to enter a customers orders (via 3 seperate panels of options), and calculate a total. Everything works just fine, and now we have to take it a step further and record the sale data in a .txt file (which will include the Crust Type, Toppings, and Extras).
I need to make it so that when a user clicks the calculate button, it also writes to a file (in this case, SalesRecords.txt). I have it all set up, but for some reason I can not get it to work. The error I get is:
"error: unreported exception FileNotFoundException; must be caught or declared to be thrown
PrintWriter outputFile = new PrintWriter(filename);
Here's my code: (the calculate button that I am working with is indicated by a comment)
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.text.DecimalFormat;
import java.io.*;
import java.io.BufferedWriter;
[I looked up the exception I got, and just so everyone knows I made sure that the file "SalesRecords.txt" DOES EXIST. It is in the same folder as my java and class files for this program. I even tried defining the absolute file path for SalesRecords.txt and that changed nothing.
I've been closely following a tutorial series, and as far as I can tell my code is exactly the same, but not functioning.
The app throws a nullpointer exception here on "controller.saveToFile(fileChooser.getSelectedFile ());"
// Export data item
exportDataItem.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (fileChooser.showSaveDialog(MainFrame.this) == JFileChooser.APPROVE_OPTION) {
try {
controller.saveToFile(fileChooser.getSelectedFile());
[Code] ....
There are no errors popping up in the code, and I dont understand why there is a null pointer exception when Im saving this file.
Everything is working great except for my back button at line 172. It works good but if I try to click the "insert" button again. It gives me the java.lang.NumberFormatException error. Other than that it works fine, the "insert" button still works.
package userDatabasePack;
import java.sql.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Database{
//Variables
private String username2, insertUser, insertPassword;
private int insertUserId;
[Code] ....
Im trying to use num as the text on the button..... (Im trying to make it count when i press the button.)I need to make a listener for the button, and an event that adds 1. (num++)
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.*;
import javax.swing.*;
public class ClickIt {
public static void Practice()
[code]....
I am trying to check to see if the button has anything on it.
Line 81 says incompatible types: JButton cannot be converted to String ')' expected ';' expected
package PA7;
import javax.swing.JFrame;
import javax.swing.JLabel;
import java.awt.*;
import javax.swing.*;
import java.awt.event.ActionListener;
[code]...
I have been working on a problem dealing with exception handling and text input output for a few days now. The exercise is a two part exercise. The first part of the exercise I have to write a program to display the total salary for assistant professors, associate professors, full professors, and all faculty, respectively, and display the average salary for assistant professors, associate professors, full professors, and all faculty, respectfully using the what is posted on the [URL] .... Each line in the file consists of a faculty member's first name, last name, rank, and salary. The second part of the exercise I have to take my code and change it so that it
-lets the user enter the name of the file to be read,
-Uses a try-catch block to handle the FileNotFoundException displaying instead The file already exists..
... Use a second catch block to ignore any other exception thrown.
... Design your code so that, if the user enters a file that does not exist, the program prompts the user to enter again a file name.
and I need to Note: In order to catch the FileNotFoundException, you need to include import
java.io.FileNotFoundException;
package pkg14.pkg25;
import java.util.Scanner;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
[code]...
I extended the SimpleFileVisitor class. And I am able to traverse the file directories. I give a file path then have it display the files full path and out put that to a text file. Here is what i have so far.
public class Main {
public static void main(String[] args) throws IOException {
Path fileDir = Paths.get("somedirpathhere");
FileTraversal visitor = new FileTraversal();
Files.walkFileTree(fileDir, visitor);
[code]...
I am able to printout of the arraylist to the console. I cant get it to write to a text file whats in the arraylist to a text file.