I am at a loss when it comes to appending Strings to a text file in Java. I was tasked (yes, homework) to complete a program that does the following simple things:
Print out the contents of a text file to the user (got that!)
Ask the user if the want to add any customers to this text file (got it!)
Add those customer's name's, addresses, postal codes and cities. (got that too)
Verify the postal code is in the proper format (yep!)
Add the new information to the text file, and display it to the user (Nope...)
The program is, essentially, supposed to keep track of the user's customers, and store this information to a text file. However, when I run the following code, I get a number of errors:
class CreateFile implements ActionListener{ // MailOrderCreateFile.java @Override public void actionPerformed(ActionEvent ae){ String getDestination = txtDestination.getText(); file = new File(getDestination); // needed for Creating and Displaying the file currentTime = txtCurrentTime.getText(); try { FileWriter fw = new FileWriter(file);
[Code]...
What I wanted to do is that every time I press the button that will activate this part of the code, it will write to a .txt file defined in my txtDestination var (a JTextField). After the first time the file was created, it must append a new line every succeeding presses. However, everytime I do this, it just simply overwrites the contents of the .txt file. The example output would have been like this:
First time.
O R D E R D E T A I L S: Time ordered: 01/21/2015 Wed 10:21:54 PM Item number: 10 Item price: $4.59 Quantity ordered: 12,321 Total: $56,553.39
I do most of my file I/O with {Scanner} for input and {PrintWriter} for output. I've got lots of places in my code that looks like:
Scanner source = new Scanner( new File( sourceName)); PrintWriter dstntn = new PrintWriter( new BufferedWriter( new FileWriter( dstntnName)));
But when I call the constructor for {PrintWriter} up above, it overwrites whatever the original contents of the file designated by {dstntnName} were, doesn't it? Is there a way to call the constructor so that any future writes to it simply append to the original contents, instead of overwriting them?
I'm currently working on a java project simply to learn java. So far, it creates a window and makes a properties file, or appends data to it if it already exists. The problem is that I'm not quite sure how to check if the file already exists to append data to it. I'm currently using a boolean (configCreated) that appends data when true, and creates a file when false. The problem is that this boolean is always false since it's at the beginning.
So I am saving a file. it is an array of two strings each containing three words. i figured out how to save to a text file and read it back in and put it back into an array. I am using scanner.hasnext and scanner.next and i think that separates the strings into variables using the spaces in the strings. Well for my project i need to do it with a symbol instead of a space
Write a program that removes all the occurrences of a specified string from a text file. For example, invoking java Exercise14_11 John filename removes the string John from the specified file. Your program should get the arguments from the command line.
I have a problem.
Text document is Match.txt Match.txt contains a string: "Open the door John"
I tried to create a new file named doc.txt where to put the text from the Match.txt without John word
//to read from document Scanner output = new Scanner("Match.text"); //to write to document PrintWriter write = new PrintWriter("doc.txt"); //copy from original document String copy = ""; while(output.hasNextLine())
This is the code that i have used to delete particular String from text file. It works absolutely fine on eclipse and netbeans.. But on deployment(in tomcat) it fails to delete message/rename or delete original file even though all permissions for modifying the files in the folder has been given to all users.
So basically, if a line in a text file contains a certain string, that specific line will be deleted. It should probably be similair to this method?
Java Code:
/** * Replace text. * @param replace * The text to replace. * @param replaceWith * The text to replace with. */ public static void replaceSelected(String replace, String replaceWith) { try { BufferedReader file = new BufferedReader(new FileReader("data/replacer.txt"));
I am having issues insert each line of the simple textfile into a specific varible I want it to go to. For example my text file is ordered like this
Dallas 78 F North, 15 mph dallasimage Denver 29 F South, 10 mph denverimage
and I want Dallas in city variable, 78f in temperature variable, and so on until text ends, at the moment is all goes into city variable, it all prints from there! I tried inserting it into an array but it would read all the lines previous to it in addition to reusing readline and all failed.
import java.io.BufferedReader; import java.io.File; import java.io.FileReader; import java.io.IOException; public class Textreader { public static void main(String[] args) {
As you notice, each character is seperated by a hyphen (serving as its delimiter). I want to only go through 10 lines in the text, instead of all 20 of them. So, I wrote the program in such a way that I intend to reach into the indices of each character in the text file. Since there are six characters in each line so that means there are 6 indices - and there are 10 lines I only want to go through. So, 6 indices times 10 lines equals 60 indices. Hence, there are only 60 indices I need to go through. In that manner, it's like I have gone through only 10 lines through that way.
It compiled perfectly fine but upon running it, I ran through an error in the black DOS screen that says
"java.lang.ArrayIndexOutofBoundsException: 6 ".
How do I work around that?
The code I wrote is shown below...
import java.io.*; import java.util.*; public class hotandcoldclusterdeterminer_test { public static void main (String args [])throws IOException {
I am writing to a text file via user input and it is saving all the user input to the file but it is just printing one word per line. I would like it to print the string on one line and print the next string on the next line upon them hitting enter.
public void textFile() { Scanner reader = new Scanner(System.in); System.out.println("Enter file name: "); String fileName = reader.next(); File f = new File(fileName); PrintWriter p = null;
I have a large text file of 1 GB size. I need to print the line when a matching word is found in a particular line. Below is the code I am using. But if there are many lines that has the matching word, it's taking lot of time. Any solution to print the lines much faster.
Scanner scanner = new Scanner(file); while (scanner.hasNextLine()) { String line = scanner.nextLine(); if(line.contains("xyz")) { System.out.println(line); } }
I need a Java algorithm that converts a string of numbers into text. It is related to how a phone keypad works where pressing 2 three times creates the letter "c" or pressing 4 one time creates the letter "g". For example a string of numbers "44335557075557777" should decode where 0 equates to a space.
Consider in a Document if a String " Hello" is Encoded and stored as "XYZAB"
I want to search the text on document for a word "Hello" and Replace the word with "HelloWorld"
The Program will encrypt the word "Hello" and Search the file then return the encrypted code as "XYZAB" Found
Now i have to replace the word "Hello" with "HelloWorld" in encrypted form so that the Letter "XYZABEFGHI" is replace in the place of Hello where "World" is encoded as "EFGHI"
Now the Problem is If there is more number of occurrence of the word "Helloworld" exist in the file... How can i Replace only one particular occurrence What can be done to select the particular occurrence.
I have attached my java program for Encryption along with this mail for your ease of use.
I have a program that reads lines of text, but some of the lines of text aren't applicable and break the program. I'd like to put a letter in front of the lines in the .txt file I want to use, such as a #.
I need to make an if loop that'll check for the first letter on the line being #, and use the line in the program if true and skip if false. I'm guessing a boolean variable would be useful here to be true or false depending on the presence of #, but I don't know how to only read the first letter of each line, how can I do this?
Just a quick question about the formatting of text files when using Java. I created a text file called Discount Fly that keeps track of things like a person's name, address, etc. Here is roughly what it looked like in the .txt file:
Name Address Postal Code Jane Doe Anywhere St, 123 1A2 B3C
However, when I run this code:
static String firstOutput = ""; public static void main(String[] args) throws IOException { BufferedReader fileRead = new BufferedReader(new FileReader("C:UsersOwnerDocumentsDiscountFly.txt")); String fileLine = ""; for (int i = 0; i < 12; i++) { fileLine = fileRead.readLine(); if (fileLine == null) { break;
[Code] ....
It prints out into JOptionPane as: NameAddressPostalCode JaneDoe Anywhere St, 123 1A2 B3C
Is there anyway to maintain the formatting in JOptionPane? Also, I am new to writing programs that read from text files, so if somethings up with my code (i.e. java conventions) ...
I am cleaning up print logs from an old system to be used in excel. I can get them down to each value is separated by a comma and looks like this.
TIME,1009 9/18/14,F/A RATIO,0.7590,NET AIR CNTS,66018.2,NET FLAG CNTS,50107.5,BKGROUND CNTS,61.0BW OF FLAG,49.807,DFRAC,-0.1834,ZFRAC,0.0000UP AIR TEMP,104.32,LO AIR TEMP,98.51,SOURCE TEMP,91.11,RCVR TEMP,97.95,,UP HEAD TEMP,93.89,LO HEAD TEMP,81.26
TIME,1026 9/18/14,F/A RATIO,0.7589,NET AIR CNTS,66026.3,NET FLAG CNTS,50107.4,BKGROUND CNTS,61.0BW OF FLAG,49.829,DFRAC,-0.1660,ZFRAC,0.0000UP AIR TEMP,104.93,LO AIR TEMP,98.42,SOURCE TEMP,92.65,RCVR TEMP,99.49,,UP HEAD TEMP,94.82,LO HEAD TEMP,82.23
TIME,1042 9/18/14,F/A RATIO,0.7584,NET AIR CNTS,66076.3,NET FLAG CNTS,50109.2,BKGROUND CNTS,61.0BW OF FLAG,49.955,DFRAC,-0.0652,ZFRAC,0.0000UP AIR TEMP,104.72,LO AIR TEMP,97.91,SOURCE TEMP,93.36,RCVR TEMP,99.52,,UP HEAD TEMP,95.31,LO HEAD TEMP,82.47
Where value follows its header. how can i export this to csv or excel with rows and columns?
I have saved emails that are stored in to text files and I want to retrieve the Sender, Reciever, Subject and the Email Content.I am using From: as a delimiter and To: as a delimiter and Subject as a delimiter and I am not sure what delimiter I should set for the email content.Also, there can be emails that will have comments after the message content and I plan on using the delimiter Comments:.
Any example of what delimiters I should use it would be great. Also I would like to know how check whether or not a delimiter exists so that I can print out the comments if it exists and if the file does not have comments, it prints out nothing.
01. pickup the selected text file and read the line by line and output the text in to visual text pane.
what i did:.
01. I wrote code that read the text file and output in to jave console/ also some of the interface.
the code read txt file:
Java Code:
String fileName = "C:/Users/lakshan/Desktop/lawyer.txt"; File textFile = new File(fileName); Scanner in = new Scanner (textFile); while(in.hasNextLine()){
[code]....
so it will read any text file dynamically and output to the text pane in interface. I think scanner code must be execute after the select the file from the browser and set the scanned result in to variable. then later out put the var as string in some jswing component?
