Read Text File And Perform Operation On Specific Columns
Dec 9, 2011
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.
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 am trying to create a file browse option in my jsp and later after browsing, all i want to do is to read that file in my jsp without saving it into that database so that i can perform encryption for it and save that encrypted file later into my database. please provide reference link so that i can refer to some applications and and move ahead with my work.
I am able to perform column operation but not able to perform row operation because i am not able to store data say a 2 matrix [][]. I need to store the data into a 2-D matrix. Here is my code:
Java Code:
import java.awt.List; import java.io.BufferedReader; import java.io.FileReader; import java.util.ArrayList; import java.util.Scanner; public class colRowRead {
This has three different classes in a package and the program itself is supposed to read and perform operations obtained from a txt file. However, I'm not even sure how to get it to perform the operations from the text file. I know that it can read the file as I was able to get the program to print the text found in the file when I ran the program with a test print to make sure that all content was being read. However, I am clueless when it comes to how to get the program to look at the text as commands.
Here is the piece of code that I am not sure where to go from as far as telling the program to read the text and perform the tasks listed.
public static void doTVoperations(){ File operations = new File("operations.txt"); if(operations.exists()) try{ Scanner n = new Scanner(operations);
I am trying to put together a small application in my spare time. Nothing major, but one thing I want it to do is accept a few inputs, and take those and add them to a table with columns for use later (printing, calculations, etc). I was originally looking at something like Jtable, but that looks just like an excel spreadsheet done Java, so not what I'm looking for.
I'm looking for something that's read-only, where I can insert data from input fields, and then perform calculations with the column data later.
This has three different classes in a package and the program itself is supposed to read and perform operations obtained from a txt file. However, I'm not even sure how to get it to perform the operations from the text file. I know that it can read the file as I was able to get the program to print the text found in the file when I ran the program with a test print to make sure that all content was being read. However, I am clueless when it comes to how to get the program to look at the text as commands.
Here is the piece of code that I am not sure where to go from as far as telling the program to read the text and perform the tasks listed.
public static void doTVoperations(){ File operations = new File("operations.txt"); if(operations.exists()) try{ Scanner n = new Scanner(operations); while(n.hasNext()){ String readOperations = n.nextLine(); String [] command = readOperations.split("[ ]"); } n.close(); } catch (FileNotFoundException e){ System.out.print("Error...TV in need of repair!"); }
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"));
I need to know how to automate a web browser (either Chrome, Firefox or Safari) to perform the following task.
Take a word from a .txt file housed on my hard drive,
1) put it into a search engine, 2) load the results, 3) click on/ open the first result, 4) open up an new tab and perform steps 1-3 again but with the next word from the .txt file. 4-5 second pauses are needed in between each step.
Additionally, I would like to automate the browser to close all the open tabs when a full stop is pulled from the .txt file.
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..
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.
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?
I am trying to read a text file into Java and split the text into tokens. Eventually I want to be able to count the number of instances of a specific word. However, at this point, when I run the file, all I get is the location of the file rather than the text in the file.
import java.util.*; import java.io.*; public class textTest3 { /** * Prints the number of words in a given file * * @param args * @throws IOException */
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.
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 can't seem to understand how to change certain line of text, inputted from a file. For this I really don't know where to begin. I have got the input from the file. But I want to change like very other line in the file. Can't seem to understand how this could be done. Is there away to access specific lines from the file and edit them? So far, i have this:
import java.util.*; import java.io.*; public class ChangeEveryOtherLine { public static void main(String[] args){ //Constructing file object representing input file File inputFile = new File("input.txt");
The basic gist is it's "A program that reads in a text file that uses a specific input format and uses it to produce a formatted report for output."
Specifically :"For this lab you will write a Java program that produces a simple formatted report. The program will prompt the user to enter a file name. This file must contain information in a specific format (detailed below). Each "block" of the file contains information for one player in a competition -- the name of the player followed by a number of different scores that that player achieved. The program should find each player's average score, median score and best and worst scores and display them in a line on the final summary report. The program should also determine which player has the highest average score and which player has the lowest average score."
I get the following errors when I try and compile it:
Enter an input file name: Project11.txt Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException... -1 at java.util.ArrayList.elementData(Unknown Source) at java.util.ArrayList.get(Unknown Source) at Project11.getMedian(Project11.java:68) at Project11.main(Project11.java:27)
I get that the error(s) reside in lines 68 and 27, among problem other areas, but I'm not exactly sure how I can fix them.
Here's my code:
import java.io.*; import java.util.*; public class Project11 { public static void main(String[] args) throws IOException{ Scanner in = new Scanner(System.in); System.out.print("Enter an input file name: "); String input = in.nextLine();
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.....
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.
personid gender height class 1 female 1.6 short 2 male 2.0 tall 3 male 1.85 medium 4 female 1.9 medium 5 male 1.7 short 6 female 1.8 medium 7 female 1.95 medium
for eg i have to find minimum and maximum height from column height.
I have to write a program for sorting an array of random numbers by the users choice. These random numbers are stored in a text file, which the user inputs, and is then stored into an array for sorting. I won't have a problem with the sorting algorithms, but I've never had to read a text file and store it into an array before
The text file has the numbers stored like so : 148 626 817 4 312 652 643 etc....
I gather that I'll probably have to user the Scanner for the user to input the text file name, but how do I store it to an array? So far I only have the bones of the program done, like so
import java.util.Scanner; public class SortingAlgorithms { public static void main(String[] args) {
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
I am trying to read in lines of text from a file then prints out the text. I only need one 2D array and can't copy from one array to another.This how the file looks like:
4 4 FILE WITH SOME INFO
I have been able to read the file but when I am trying to run my program I have blank spacing instead of an array.
import java.util.Scanner; import java.io.*; public class Array { public static void main(String[] args) throws IOException{
Write a class TextAnalysis14 which reads a text file and allows some text mining(Analyzing). Concretely the program has to support
1. total the number of words, 2. checking whether a word is contained in the text, 3. finding the most frequent word, or words in case there are more than one.
A word is a non-empty string consisting of only of letters (a,. . . ,z,A,. . . ,Z), surrounded by blanks, punctuation, hyphenation, line start, or line end. The analysis is case-sensitive.
I'm making a tree of contacts with people's names as one string and their numbers as another. I need to read that in from a .dat that is set up to have two columns, across from the names are the numbers, so i have to read that in, but I'm not sure how. Here is what I have:
Tree<String, String> tree = new Tree<String, String>(); BufferedReader br = new BufferedReader(new FileReader("/Users/katedess/Desktop/animals.dat")); String read; while((read = br.readLine()) != null) { tree.add(read); } br.close(); }
