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.
View RepliesI am trying to write method to read lines with some specification from a file. for Example,
my text file contains following:--
12-01-0113:26San Jose12.99DVD
12-12-3009:40Miami13.50Music
14-08-3010:20Arizona16.03Scientist
11-07-1009:10New York25.00ColdPlay
14-08-3010:20Arizona18.04MeetYou
14-08-3010:20Arizona50.03Scientist
11-07-1009:30New York25.00ColdPlay
11-07-1009:20New York25.00ColdPlay
tab separated values, for different columns and these are the lines only I want method to read.Now suppose if any is there as below, or even enter
12-01-0113:26San Jose12.99DVD
12-12-3009:40Miami13.50Music
14-08-3010:20Arizona16.03Scientist
11-07-1009:10New York25.00ColdPlay
14-08-3010:20Arizona18.04MeetYou
[new lines]
14-08-3010:20Arizona50.03Scientist
11-07-1009:30New York25.00ColdPlay
//This line should not be read
even this should not be read #$%^&
11-07-1009:20New York25.00ColdPlay
That particular line should be escaped. Till now I have done when the file format is proper, and it is as below:--
public static void main(String[] args) {
BufferedReader br = null;
String temp = null;
List<String> arrayRead = new ArrayList<String>();
try{
br = new BufferedReader(new FileReader("D: estingSalesData.txt"));
[code]....
So here we go with my problem:
- from the main class will arrive three variable (String name_used, int level_choose, int level_result)
I have a .txt file with this kind of formatting:
mario 1 1 0 1 0 1
carlo 0 0 0 1 1 0
...
Where I use 1 and 0 in the main for write if the level (you see that the numbers are always sixr? are egual to six level existing) BEFORE is done correct or wrong
- when in the main a user make a level a feedback coming back from the class level saying if the user made the count correctly or wrong. and i wanna replace the value (1 or 0) in the txt file with the new level result.
So i have all what i need as parameters i think.
name_used to look for the correct line in .txt file with .indexOf
level_choosed to go throught the correct index of that line
level_result (1 or 2) to be replaced with the existing one
Java Code:
public void salvaRisultati(String name_used, int level_choosed, int result_of_level) throws FileNotFoundException{
}
} mh_sh_highlight_all('java');
I am trying to write a specific byte sequence to a specific memory location on a removable storage drive. Does Java allow me a way to do this? I know the dangers in accessing memory, but the memory location of the data that will be written will never change.
how to assign a variable a memory location.
I have some problem to understand the way to make this:
In my main class a user can save his name in a txt file (and the system initially will add 6 value equals to 0) than he can choose between 6 level and make it.
example of .txt file data:
mario 0 0 0 0 0 0
carl 0 0 0 0 0 0
AT THIS MOMENT i just made other class and they work, is this new one that is hard for me. I'm trying to make a class that:
1- (first method called verificaRisultati) take name_used and level_choosed from the main and go to check in the .txt file if that level before was done right(1) or wrong(0)
and return something like "before you made this level properly" or "before you made this level incorrectly" AND THEN let the user start with the level.
2- (second method called salvaRisultati) at the end of the level i wanna pass the result (correct/incorrect) to another method of this class that will save the value (1 or 0) associated to the user in the right position.
This is the class that i'm writing:
Java Code:
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
public class ResultUsers {
[Code] ....
I really need some hint and some code example because I'm stuck. How I can take exactly the line with the user name? How I can correctly split the line in an array and then read/modify the value for that level?
I have wrote this class who read from text line by line and save the words in fileOnTable.. Now i don't know what to read in ReadOffer to save the words in object offers and return this.. One more question.. What JUnit test can write for this code..?
package com.example.crazysellout.UserSide;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
[Code] ....
how to read file line by line ? Namely my input file I want to read look as follow:
AAA 1, 1
12 222 12
AAA 2, 2
11 122 11
My output file should look as follow:
1, 1, 12
1, 1 222
1, 1, 12
2, 2, 11
2, 2, 122
2, 2, 11
I think the lines need to be stored in ArrayList, then I would like those lines to write to csv file, but how on read I can construct such output file? This is my code for reading file
public ArrayList readFile(String filename)
{
try
{
[Code]....
I know how to append text to a File using the true argument but I would like to be able to append to a certain line In the file.Basically I've made a simple html page with Image links to different sites. I'm trying to make an app that will take a new site as Input and append It to the html file before the </body> tags.
View Replies View RelatedHow to modify a specific line of a file in java. File name must be accepted from command line.
View Replies View RelatedSo 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"));
[code]....
I have the following HashMap:
// 2009
nobelPrizeWinners.put("2009 Physics",
new PrizeWinner[] {new PrizeWinner("Charles K.", "Kao"),
new PrizeWinner("Willard S.", "Boyle"), new PrizeWinner("George S.", "Smith")});
nobelPrizeWinners.put("2009 Chemistry",
new PrizeWinner[] {new PrizeWinner("Venkatraman", "Ramakrishnan"),
[Code] .....
At the moment, my output is:
2008: Chemistry: Osamu Shimomura, Martin Chalfie, Roger Y. Tsien
2008: Economics: Paul Krugman
2008: Literature: Jean-Marie Gustave Le Clézio
2008: Medicine: Harald zur Hausen, Françoise Barré-Sinoussi, Luc Montagnier
2008: Peace: Martti Ahtisaari
[Code] .....
However, I need a blank line between the final entry of 2008 and the first entry of 2009.
I need to search a txt file for a specific keyword and then output all the lines that contain that keyword. Right now I I think I have my search done but I don't know how I would print the whole line.
TextIO.readFile("xxx.txt");
String search;
String word;
int count=0;
TextIO.put("Please enter your search word: ");
search = TextIO.getln();
while (!TextIO.eof()) {
word = TextIO.getln();
count = count+1;
if (search.equalsIgnoreCase(word)==true){
TextIO.put(count + "-");
TextIO.put(word);
Right now it doesnt even let me enter in any values for the search. Not sure what I've done wrong..
I am trying to have a program go on one of the stock trading websites and read the number a stock or currency is at and display or save it. I have it reading and displaying the binary code but I don't see how to have it find the numbers I would like to get.
On the site you would have to go on the page and click some tabs to trade and maybe the stock you would like, it doesn't really matter what one it returns as this is more just an idea. Although I would like to have it search out a selected stock eventually to take it to the net level. I think my biggest problem is I can't see how to access the stock numbers in the code. I looked for different click events but don't see how to have a program do this.
I do not intend to have it display all the code like it is now. I just did it like that to see what I was getting. I will just have a small toolbar with options and a display.
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
public class StockTracker {
public static void main(String[] args) {
[Code] ......
I am checking how to do following task.
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?
How do i write a method in java that will add a <b> or <em> tag to a specific word regardless of case or punctuation for example for "run forest RUN!" adding bold to run would be
<b>run<b> & <b>RUN!<b>
public void addTag(String word, String tag) {
I am somewhat of a java newbie (learned it awhile back and just getting back to programming some again.) I have a text file of data much larger than this, but here are the first ten rows and first 10 columns.
39755320111041730140.633038085-2.117082366149.069997
39850320111041730150.633038085-2.117082511148.309997
39955320111041730160.633037998-2.117082293149.509997
40055320111041730170.633037945-2.117082351149.239997
.......
I can read and write all the data back out to files. But I am not sure about a few things.
First would it be best to use BufferedReader and OutputStream such as:
public static void main(String[] args) throws IOException {
BufferedReader bReader = new BufferedReader(new FileReader ("testdata.txt"));
BufferedOutputStream bytesOut = new BufferedOutputStream(new FileOutputStream ("outfile.txt"));
Second, I was then going to initialize an array but I might have 30 or more columns of data, of which I might perform and output only 10 columns to my output.txt file so is this a good way?
Third, I only want to perform operations (such as average the data, convert units or multiply two columns together) on 10 of the 30 plus columns and print out results to output.txt file. For example, In testdata.txt file above, I want to skip first seven columns. I then want to take column 8 and multiply by 100 then divide by 3 and output result to output file. I want to do same for column 9. Column 10 I want to multiply by different number (by 3.5).
i start work with TxT files. And i need know how to write text in the next line if file exist. My code just last text replace new.. Here code :
Main :
package YoYo;
import java.util.Scanner;
public class Main {
static String atsakymas;
static String FileName;
[code]....
i am fairly new to java but have made a few projects so i do know most aspects that would allow me to complete the task its just i have been stuck at the same place now for 2 days.The project is to create a java program that can read specific data within a csv file to work out the averages etc. The csv file is a database of different weather stats . an example of the first 12 months of the csv file is below..
[CSV FILE]
year ,month,average rainfall etc
1946 15.70.616108.131.5
1946 28.23.56111.871
1946 38.82932.9 102.9
1946 414.16.3029.2 150.5
1946 513.96060.7 143.6
[code]...
I know that once the data is indexed i can than use a double to find the average of the 12 specific pieces of data and so on. once this is complete i should than be able to transfer the data to a simple graph.
I'm going to be taking an object oriented paradigm using java during intersession in a few months. I'm trying to brush up on it a bit. The problem is. Write an application that displays the numbers 1 to 4 on the same line, with each pair of adjacent numbers separated by one space. Write the program using the following techniques:Use one system.out.printLn statement.Use four system.out.print statement.Use one system.out.printf statement.
This is what i have so far .
Java Code: public class Display
{
public static void main(String [] args) {
System.out.print("1 ");
System.out.print("2 ");
System.out.print("3 ");
System.out.print("4 ");
System.out.println(" ");<----is that what that is supposed to look like, and where it goes?
System.out.printf(" %s %s %s %s ");????
}
} mh_sh_highlight_all('java');
i cant test this my console isn't working right, and i haven't finished my compiler install.
Write a program to reverse each word in line(sentence)?
View Replies View RelatedI was wondering if I could write this code in one line.
import java.util.Scanner;
public class Test
{
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
char ch = sc.next().charAt(0);
}
}
Can I combine "import java.util.Scanner","Scanner sc = new Scanner(System.in);" and "char ch = sc.next().charAt(0);" in one statement? The object created from the class Scanner may be anonymous but it doesn't concern me!
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;
[Code] ....
How can i use java for usb device? I want to read or write in a usb device in java. I've looked for in the web and i didn't find anything!
View Replies View RelatedSo I'm trying to read 11 values from a text file, each value on a separate line. The first value I use as loop control to run through calculations on the other ten and finally output both the numbers and the calculations to the console and an output file. I'm not getting a compiler error or a runtime error but my loop seems to stop after reading the first line. It also doesnt seem to be writing to my output file but does create it when I run the program. This is what my text file looks like
10
150.4
88.4
-3.14
499.4
799.4
1299.8
0
1900.2
901.7
4444.4
This is what my program looks like
import java.util.*;
import java.io.*;
public class assignment7scratch
{
Toolkit_General toolKit = new Toolkit_General();
public static void main (String[]args)throws IOException
[Code] .....
so I dont get an error but this is what my output looks like
----jGRASP exec: java assignment7scratch
This program reads a list of values representing number of miles driven by individuals. It will output the dollar amount their rental cars cost.
Number of miles traveled on the left as well as amount reimbursed on the right
-----------------------------------------------
Miles Driven Amount reimbursed
150.427.072
----jGRASP: operation complete.
it also doesn't write anything to my output file, though it does create one.
So I'm having a problem with the .hasMoreElement() method. I try to read lineOfInput for a file which contains:
Hobbit, Long,t@gmail.com,475-555-4444,3
Long, Hobbit,b@yahoo.com,445-222-5342,2
Hobbit,Long,b@yahoo.com,465-222-5342,2
Help,Yerp,,455-222-2222,4
but when i get to the ,, on the last line I get a NoSuchElementException and the program crashes.
StringTokenizer inputField = new StringTokenizer(lineOfInput, ",");
while(inputField.hasMoreElements()) //for each fields is a line
{
lastName = inputField.nextElement().toString();
firstName = inputField.nextElement().toString();
email = inputField.nextElement().toString();
phoneNumber = inputField.nextElement().toString();
level = Integer.parseInt(inputField.nextElement().toString());
}
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?
View Replies View Related