File Handling - Dynamically Update XML File As It Is Being Edited
Feb 11, 2014
I'm writing a program that dynamically updates an xml file as it is being edited. It needs an add function, delete, and save, and so far, I've gotten only the add function working properly. I've got a delete method that works when I run only that method, but not when I run the program as a whole. I don't get any exceptions or errors and I'm trying to edit the file via printwriter. It creates a new temporary file with the new xml with the deleted section and then overwrites the current .xml file. It runs flawlessly when I run only the delete method, but not when I run the program as a whole.
public static void removeFromFile(String file, String lineToRemove) {
try {
System.out.println("Removing: " + lineToRemove);
File inFile = new File(file);
if (!inFile.isFile()) {
System.out.println("Parameter is not an existing file");
I'm writing a program to dynamically update an xml file to add, delete, and edit entries in the file. I've run into an issue with the add method because when I write into the file, a random letter is added before the line. EX:
I want to add "<item> ..." to the end of the list of entries, but when it is added, this is what is added "Z <item> ..."The spacing for the <item> is correct, however, I don't see where or why the Z is added.
public static void insertItem(Item i) { try { String insert = " <item>"; String text = ""; Scanner in = new Scanner(file);
I am facing a problem while executing a task. My task is to make such a code which will search for my source code file (abc.java) in all directories and then displays the code in textarea inside frame and along with that i also have to display the path of the file in text field. I have coded something but i am really not getting anywhere near my task.
when open file "rahul.txt"so it shows characters which i stored not byte code i want to stored in file byte code. Now i have a problem for file handling it is not store bytes into myfile. it stores character not bytes.
package com.fileh; import java .io.* public class Writedata { public static void main(String args[]) { try{ FileOutputStream fout= new FileOutputStream("rahul.txt"); String s="my name is rahul"; byte[] b =s.getBytes(); fout.write(b); fout.close();
[code]....
and second problem is that when i use FileInputStream to read file rahul.txt so it did not read .
I created a GUI using Java with Buttons, Pictures and labels.When one of the buttons is pressed it increases the price, which can be seen by the labels increasing the necessary amount.What I would like to be able to do in my GUI is allow the user to record details of the sale and be able to display the sales of past customers to date, by this I mean when I click one of the buttons it will record the amount of that item into a file and when I press the another button, not the same button as the items, it will show the user the existing orders that have been taken in the past.
I am new to JSF, trying to customize the primefaces picklist, I want to update the picklist Source List dynamically on certain events like onclick or change?
I tried to write an Listener and populate the dualModel, the call is going to the method and List is getting updated but in UI, the old list is only maintained . I have also asked this question in stackoverflow ,
Refer this link for further details : stackoverflow [URL] .....
Assume we have 2 files that are input.txt and output.txt Input.txt has Name||Age||email||contact No||Name1||age1||email1||contact No1||name2||Age2||email2||contact no2||etc...
initially the output.txt does not have any record.using a java program we have to make it as
Names in the input file:Name,Name1,Name2,Name3 Ages in the input file:Age,Age1,Age2,Age3 email id in the file: email, email1, email2 Contact no in the file:contact no, contact no1,contact no2
I'm doing this assignment in which i have to write some products in csv file...but as u can see in csv file two products are same "Cooking Oil"..so any method that can add two same product's quantity and their amount and write them in file
import java.util.*; import java.io.*; public class SalesbyTransactionMonth{ private static final String fileName = "Data.txt"; private static final String fileName1 = "sales_by_trans_month.csv"; String line = "";
I am trying to learn how to use file input/output in addition to exception handling... The problem is my textbook wrote this chapter for a version of Java that hasn't come out yet, so everything I do "according to the textbook" doesn't work. any feedback on correcting these exception errors because I am not sure what is causing them or how to fix them.
I was able to have it display the name of the book in the Book.txt file, but when I added the second part if the file doesn't exist, that's when the errors came up and it wouldn't compile.
import java.io.*; import java.util.*; public class DisplayBook { public static void main(String[] args) { try { File book = new File("Book.txt"); FileInputStream in = new FileInputStream(book);
[Code]...
These are the compilation error messages I am receiving: (I have managed to get it down from 7 errors to just 4, but now I'm stuck)
DisplayBook.java:15: error: unreported exception IOException; must be caught or declared to be thrown while ((letter = in.read()) != -1) //if file exists, displays book title ^ DisplayBook.java:24: error: unreported exception FileNotFoundException; must be caught or declared to be thrown
I have a flat file (.txt) with contents in a predefined format. I need to parse and look for a particular content and update it. How can i achieve this using Java.
I am trying to remove a line based on user input. myFile.txt looks like:
Matt Brian John
However when I enter "Brian" (to remove this line), It is deleted on the temp file (myTempFile.txt), but not renamed back to the original file (myFile).
I have studied about the hierarchy of exception classes in which Throwable class comes at the top and two of its direct subclasses are Error and Exception..I just want to ask if in some code snippet we throw an instance of Error or its subclass within the try catch block then will that be also called "exception handling" ? I am asking this because Error class is not a child class of Exception therefore cant be said an Exception, therefore handling the same should not be called exception handling
Im trying to embed swt browser in swing , the problem that I have is that i cant change the value of JTextField even when i request focus ,when i try to give input the input goes in the browser's page bar..
public static void main(String[] args) { final SwtBrowserCanvas browserCanvas = new SwtBrowserCanvas(); final JTextField textField = new JTextField(15);
I've tried everything but in vain..I want to save the data from the table into the database, I can easily connect to the database. All I want is how to get the values from the table. I've tried this method to get the values but its not working because of the contructor error in the BgTableModel class.
Tried Method public void writeBgEdu() { int last=gtm.getRowCount(); System.out.println(last); for( int i=0;i<last;i++) { if(((String) gtm.getValueAt(i,0))!=null)
I am trying to create an array list without using the built in arrayList class that java has. I need to start the array being empty with a length of 5. I then add objects to the array. I want to check if the array is full and if not add a value to the next empty space. Once the array is full I then need to create a second array that starts empty and with the length of the first array + 1.
The contents of the first array are then copied into the new array without using the built in copy classes java has and then the new array ends up containing 5 elements and one null space the first time round. The first array is then overwritten with the new array containing the 5 elements and the null space. The process then starts again adding values until the array is full which will be 1 more value then recreating the second array empty and the length of the first array + 1. This is my attempt at creating this but I have run into multiple problems where I get only the last value I added and the rest of the values are null:
public class MyArrayList { public Object arrayList[]; public MyArrayList(Object[] arrayList) { this.arrayList = arrayList;
I am creating a web application that runs on server X(unix) and it has another unix system mounted on it. I want to generate the file tree structure of this mounted unix file system and show it on to a web application so that users can select a file and move it onto this current unix machine.
I know this sounds stupid and you may want to say why cant we directly copy the file, I am doing a proof of concept and using this as a basis.
I am working on a project that requires me to build a database with random access file, representing products, the base product contains a name (about 30 characters), a price (double), and a quantity (integer). I have worked on this project for probably 15+ hours and have tried so many things and feel like I've barley made any progress...
The part i am really struggling with is taking the data from the text file and creating an object array with it using the product class. Once ive accomplished that, i have to use that data to create a random access file with the data.
Here is the base Product class that must be used to create the objects for the array.
public class Product { public String pName; public String stringName; public double price; public int quanity;
[Code] .....
And then here is the data from the text file that i must extract to use to create product objects.
These continue for about 40-50 entries, they are not separated by a blank line though i had to add those so it would display correctly, each entry is on its own line with name separated with spaces, then price after a comma, then quantity after the second comma.....
I am working on a project that requires me to build a database with random access file, representing products, the base product contains a name (about 30 characters), a price (double), and a quantity (integer). I have worked on this project for probably 15+ hours and have tried so many things and feel like I've barley made any progress...
The part i am really struggling with is taking the data from the text file and creating an object array with it using the product class. Once ive accomplished that, i have to use that data to create a random access file with the data. Here is the base Product class that must be used to create the objects for the array.
public class Product { public String pName; public String stringName; public double price; public int quanity;
[Code]...
these continue for about 40-50 entries, they are not seperated by a blank line though i had to add those so it would display correctly, each entry is on its own line with name seperated with spaces, then price after a comma, then quanity after the second comma.....
I am working on a project that requires me to build a database with random access file, representing products, the base product contains a name (about 30 characters), a price (double), and a quantity (integer). I have worked on this project for probably 15+ hours and have tried so many things and feel like I've barley made any progress...
The part i am really struggling with is taking the data from the text file and creating an object array with it using the product class. Once ive accomplished that, i have to use that data to create a random access file with the data.
Here is the base Product class that must be used to create the objects for the array.
public class Product { public String pName; public String stringName; public double price; public int quanity; //Constructor public Product( String pName, double price, int quanity )
[code]....
and then here is the data from the text file that i must extract to use to create product objects.
Dill Seed,938,34
Mustard Seed,100,64
Coriander Powder,924,18
Turmeric,836,80
Cinnamon (Ground Korintje),951,10
Cinnamon (Ground) Xtra Hi Oil (2x),614,31
Cinnamon (Ground) High Oil (1X),682,19
these continue for about 40-50 entries, they are not separated by a blank line though i had to add those so it would display correctly, each entry is on its own line with name separated with spaces, then price after a comma, then quanity after the second comma.....
New to programming. Am supposed to create a program that reads a text file (of integers) and computes a series of computations on these integers. I don't have the code for the integers in my code yet, (i know how to do those), but am struggling getting the array to simply print in the print writer. I have the user select a text file, read the file with a scanner, and then save the computations done from my code into another file. specifically, the problem is as follows: Write a program that uses a file chooser dialog to select a file containing some integers. The file contains an integer N followed by N integers. The program then uses a file chooser dialog to let the user specify the name and location of an output file to write results to.The data written to the output file will be as follows
(1) The original list of N numbers from the input file, (2) The original list of N numbers printed in reverse order of how they appear in the input file. (3) The sum and average of these numbers, (4) The minimum of all the numbers, (5) The maximum of all the numbers.
is my current exercise.so far i have gotten the code to create a file, and ask the user to input their age.what should i use to save what the user writes into the file?
Java Code:
package assignment7; import java.io.*; import java.util.*; public class Exercise2 { public static void main ( String [ ] args ) throws IOException { Scanner scan = new Scanner(System.in);
