Read Three Files Using MultiThreading And Write Into A New File
Apr 21, 2014
I got a question in my last interview, its all about multithreading, interviewer asked me to write a program, to write the contents of three files(F1,F2,F3) in to a new File F4, using multithreading , first thread should read the first file and second thread should read second file, so the File F4 should contain F1's contents in first then F2's contents after that etc. I tried to give my best shot, but i couldn't get a way to ensure that the first thread is reading the first file and write to F4 then second thread reading the second file and writing once first file is written completely into F4 and so on ..how to do this?
My background is mainframe and i'm new to java. We're moving from mainframe to the java world and I'm trying to achieve a task. I have a main folder and then bunch of sub folders and each sub folder has bunch of xml files, files size are varies some of them are 900kb. I need to read these xml files and send the output to the txt file (comma separated).
Some possible options or sample example... Please find below the sample xml file. I need to extract information's only where
I have seen different methods of creating and reading files (specifically text files) in Java. The PrintWriter method or the Formatter with a Scanner to read the file, using a BufferedWriter with a BufferedReader, etc. They will all read/write text files, but from what I understand they do so in different ways. When would it be more beneficial to use a buffered writer than, say, PrintWriter, which is much simpler code-wise? Is there a "best" way to handle i/o in general in Java?
I'm rather new to programming and I'm trying to make a gui program that will allow the user to create text files. They will be prompted to enter what they'd like to save their file as and then they will be allowed to input text to that file . They will also be allowed to open their files to modify or view its contents. So to start things off, I'm making a prototype if you will.. I've been able to save to a file the problem occurs when I try to read/display it.
Main Class:
public class MainActivity { public static void main(String[] args) { // Access to other classes WriteFile writer = new WriteFile(); ReadFile reader = new ReadFile();
I wanna learn to create a method where I use a scanner or any other way to input.The stuffs I input will be strings. The whole thing will be like a destination creator.So if I input the string USA, it will write this to a file:
1:USA
When I go to the method again the ID will be added so if I input UK, the file will contain:
1:USA 2:UK
Now if I terminate the program, next time when I run it again it will be able to read the ArrayList, so if I wanna go to the method again and write: Norway the file will contain:
1:USA 2:UK 3:Norway
Later I also want to be able to use println to show all of these lines from the file, as well I would like to be able to delete an ID, so if I delete ID 2 the file would contain:
1:USA 3:Norway
I'm quite new to Java, I'm in a Java course since soon 3 weeks back and I have sure learned a lot, all the loops and basic statements that exist in most languages, but now when it comes to this I just don't understand.
What i basically do is that i read the information of what course that needs to be updated with a new course date and then i log into the wordpress page and navigate to the course and add the date.
I need the java program to be able to do these following actions.
1. Open a webpage
2. write to a form
3. click a button
4. search for a text on screen
5. click on a specific place on the screen/click on a link
I have a program that is a XML-parser, and it works fine when I'm running it from NetBeans. But when I create a JAR-file and run the very same program, it cannot find the xml file. Consider this small program that addresses my problem:
I am trying to make a Library that will read some Input Files from a File . Like When We Enter Nuber from a System.in
1 2 45 667
77 34
and then store these values in int[] array
What I want is I Save all these values in a File and at Run time pass path of that file to command line arguments and then int[] array will be initialize using that
I'm trying to write information into a file using PrintWriter. The program complies correctly but when it get's to the following part of the program, an error is given. "Exception in thread 'main' java.io.FileNotFoundException" What is wrong with it?
System.out.print("Enter the filename:"); filename = kb.nextLine(); PrintWriter outputFile = new PrintWriter(filename); outputFile.println(balance); outputFile.print(item1+" "+item1Price); outputFile.println(" "+item1Quantity); outputFile.print(item2+" "+item2Price); outputFile.println(" "+item2Quantity); outputFile.print(item3+" "+item3Price); outputFile.println(" "+item3Quantity); outputFile.close(); System.out.println("Data written to the file.");
I am trying to do a read/write int property called currentQuestionIndex. This property is the index of the question currently selected, and the value of the property is 0 when a DrivingTest object is first created. I dont understand how to do this. I am not sure how to get the index of the current question. i was trying to use an iterator but i dont think i was doin it right. My question class that hold all my data
package cs320Labs.servlet; public class Question { String description; String answerA; String answerB; String answerC; int correctAnswer;
I have to write a diff which will compare two txt files, diff have to return changes and additional lines in console with indicating in what file and line.
I'm refitting a snippet of code I found on the net to write stuff into text files. After a bit of fiddling, here's what the code looks like in one of my classes:
public void addItem(String Item){ try{ Writer out = new OutputStreamWriter(fos, "UTF8"); out.append(Item); out.flush(); // out.close(); } catch (IOException e) { System.out.println(e.toString()); } }
The original snippet included the close() method. However, when I tried to do a test run writing multiple lines, I'd get an IOException about the stream being closed. I removed the close() method line, everything seems to work the way I want it, but I just wanna know if there's anything I'm missing out on by not having the close() method anywhere, especially when the IDE finds it important enough that it lit a warning about the stream not being closed somewhere as I was repurposing the original snippet.
I'm trying to use graphics for my programs and here I'm trying to write a program that searches through files for text received from a JTextField. However, it does not seem to be working as my message is not displayed when text is found...
I am fallowing programming tutorials on youtube.And this code is for reading zip files content.I did the same things like in the video.But Code dosent work
I have a question for the read and write method in file.In my code for writing i m using PrintWriter and for reading Scanner.So i m saving data to file and when is need it i m reading from the file.but i also have to delete specific data from it.Is there a way to delete a specific line from the file?When i google my problem i found that is better to save your data to temporary file and then to the final.
I need to read folder structure from the excle file and need to read all the files which are available inside folder structure.folder structure like below
c:Migrate C:MigrateMigrateFiles ... ... ..etc.
I am ble to read files which is avalibale in all the folders with single thread,i want to read those files with multiple threads,each thread shoud reads the files from different folder. here how to read.
I've written a program to read files in a directory but I'd like for it to only read the text files of that directory.
import java.io.*; public class Data { public static void main(String[] args) throws IOException { String target_dir = "C:files"; File dir = new File(target_dir); File[] files = dir.listFiles();
I have a database of 100,000 research articles, all as full text. From a GUI I'm building ( w. Scene Builder and NetBeans) I would like to enter a journal name and have some of the articles read into memory, in a background thread. Then I would analyze them, also in a background thread. Then I would write various results, e.g., lists of authors or titles, wordlists, to the GUI for examination by a user.
How to create background threads from my model that will read from and write to a GUI using Tasks and/or Services.
I'm supposed to write a computer based testing program using files. I have started writing however, I am stuck. I am to prompt the user to enter the file name 'test.dat" and if something different is entered then a error message should be displayed. Also the file will create an input stream for the data using the file. I am to have the user enter other information about an employee and then write the record to the file.
The program should be created so when the user enters "quit" the loop is terminated and the file is closed. I'm not asking for code. I was just giving a brief synopsis of the project. Where I am stuck is I wrote the first part of the program that creates the file; however when I enter a wrong file name the exception error message does not display. The code is below:
import java.io.*; import java.lang.*; import java.util.*; public class Project5Write { private Formatter x; public void openFile(){
