We Keep Coding

Why does the stream position go to the end

I have a csv file, after I overwrite 1 line with the Write method, after re-writing to the file everything is already added to the end of the file, and not to a specific line
using System.Collections;
using System.Collections.Generic;
using UnityEngine.UI;
using UnityEngine;
using System.Text;
using System.IO;
public class LoadQuestion : MonoBehaviour
{
int index;
string path;
FileStream file;
StreamReader reader;
StreamWriter writer;
public Text City;
public string[] allQuestion;
public string[] addedQuestion;
private void Start()
{
index = 0;
path = Application.dataPath + "/Files/Questions.csv";
allQuestion = File.ReadAllLines(path, Encoding.GetEncoding(1251));
file = new FileStream(path, FileMode.Open, FileAccess.ReadWrite);
writer = new StreamWriter(file, Encoding.GetEncoding(1251));
reader = new StreamReader(file, Encoding.GetEncoding(1251));
writer.AutoFlush = true;
List<string> _questions = new List<string>();
for (int i = 0; i < allQuestion.Length; i++)
{
char status = allQuestion[i][0];
if (status == '0')
{
_questions.Add(allQuestion[i]);
}
}
addedQuestion = _questions.ToArray();
City.text = ParseToCity(addedQuestion[0]);
}
private string ParseToCity(string current)
{
string _city = "";
string[] data = current.Split(';');
_city = data[2];
return _city;
}
private void OnApplicationQuit()
{
writer.Close();
reader.Close();
file.Close();
}
public void IKnow()
{
string[] quest = addedQuestion[index].Split(';');
int indexFromFile = int.Parse(quest[1]);
string questBeforeAnsver = "";
for (int i = 0; i < quest.Length; i++)
{
if (i == 0)
{
questBeforeAnsver += "1";
}
else
{
questBeforeAnsver += ";" + quest[i];
}
}
Debug.Log("indexFromFile : " + indexFromFile);
for (int i = 0; i < allQuestion.Length; i++)
{
if (i == indexFromFile)
{
writer.Write(questBeforeAnsver);
break;
}
else
{
reader.ReadLine();
}
}
reader.DiscardBufferedData();
reader.BaseStream.Seek(0, SeekOrigin.Begin);
if (index < addedQuestion.Length - 1)
{
index++;
}
City.text = ParseToCity(addedQuestion[index]);
}
}
There are lines in the file by type :
0;0;Africa
0;1;London
0;2;Paris
The bottom line is that this is a game, and only those questions whose status is 0, that is, unanswered, are downloaded from the file. And if during the game the user clicks that he knows the answer, then there is a line in the file and is overwritten, only the status is no longer 0, but 1 and when the game is repeated, this question will not load.
It turns out for me that the first question is overwritten successfully, and all subsequent ones are simply added at the end of the file :
1;0;Africa
0;1;London
0;2;Paris1;1;London1;2;Paris
What's wrong ?
The video shows everything in detail

Resetting Java while loop

I currently have 2 loops, one which gets a timestamp, and another while loop to find the mapped information based off that time stamp and output in a certain way.
Issue I have is I am currently looping through a text, and want it to start reading the file from the beginning again when the isdone="N" for the second loop, however, this does not seem to be the case.
Code so far:
public static void organiseFile() throws FileNotFoundException {
String directory = "C:\\Users\\xxx\\Desktop\\Files\\ex1";
Scanner fileIn = new Scanner(new File(directory + "_temp.txt"));
Scanner readIn = new Scanner(new File(directory + ".txt"));
PrintWriter out = new PrintWriter(directory + "_ordered.txt");
ArrayList<String> lines = new ArrayList<String>();
String readTimeStamp = "";
String timeStampMapping = "";
String outputFirst = "";
String outputSecond = "";
String outputThird = "";
String previousTimeStamp = "";
String doneList = "";
String isdone = "";
int counter = 1;
// Loop to get time stamps
while(fileIn.hasNextLine()) {
readTimeStamp = fileIn.nextLine();
if(readTimeStamp != null && readTimeStamp.trim().length() > 0) {
readTimeStamp = readTimeStamp.substring(12, 25);
System.out.println(readTimeStamp);
// Previous time stamp found, no need to loop through it again
if(doneList.contains(readTimeStamp))
isdone = "Y";
// Counter in place to stop outputting the first record, otherwise output file and clear variables down
else if(!previousTimeStamp.equals(readTimeStamp) && counter > 1) {
out.println(outputFirst + outputSecond + outputThird);
System.out.println("Outputting....");
outputFirst = "";
outputSecond = "";
outputThird = "";
counter = 1;
}
// New time stamp found, start finding values in second loop
else
isdone = "N";
// Secondary loop to find match of record
while(readIn.hasNextLine() && isdone.equals("N")) {
System.out.println("Mapping...");
timeStampMapping = readIn.nextLine();
System.out.println(timeStampMapping);
// When a record has been found with matching time stamps, start ordering
if(timeStampMapping.contains(readTimeStamp)) {
previousTimeStamp = readTimeStamp;
System.out.println(previousTimeStamp);
if(timeStampMapping.contains("[EVENT=agentStateEvent]")) {
outputFirst += timeStampMapping + "\r\n";
} else if(timeStampMapping.contains("[EVENT=TerminalConnectionCreated]")) {
outputSecond += timeStampMapping + "\r\n";
} else {
outputThird += timeStampMapping + "\r\n";
doneList += readTimeStamp + ",";
}
counter++;
}
}
}
}
System.out.println("Outputting final record");
out.println(outputFirst + outputSecond + outputThird);
System.out.println("Complete!");
out.close();
}

You can use Scanner.reset() to reset it to the beginning of the file. For example, after your second while-loop include:
if (isdone.equals("Y")) {
fileIn.reset();
}
Btw: why are you using String for isdone instead of boolean??

How can one get a file's path from an ftp server?

This code gets the file name, but I want to get the file path:
private List <String> checkFiles(FTPClient clients){
List <String> it = new ArrayList <String>();
try {
FTPFile[] ftpFiles = clients.listFiles();
int length = ftpFiles.length;
for (int i = 0; i < length; i++) {
String name = ftpFiles[i].getName();
Calendar date = ftpFiles[i].getTimestamp();
Log.v("aasd", name );
it.add (name);
}
} catch(Exception e) {
e.printStackTrace();
}
return it ;
}

The path is in the client, not the files.
String path = clients.printWorkingDirectory()

if you want specific path
client.changeWorkingDirectory(PathName) eg client.changeWorkingDirectory(folder1/folder2) where folder 2 is inside folder 1
System.out.println(client.printWorkingDirectory)
printWorkingDirectory gives the current path

Below code finds that all files path in any folder on ftp server.
ftpPath is likes that "ftpserver/folder". List contains paths of all files in folder.
public List<string> GetFilesPath(string ftpPath)
{
FtpWebRequest request;
string FtpServerPath = ftpPath;
List<string> filePathList=new List<string>();
try
{
request = WebRequest.Create(new Uri(FtpServerPath)) as FtpWebRequest;
request.Method = WebRequestMethods.Ftp.ListDirectoryDetails;
request.UseBinary = true;
request.UsePassive = true;
request.KeepAlive = true;
request.Credentials = new NetworkCredential("ftpuser", "ftpPassword");
request.ConnectionGroupName = "group";
Stream rs = (Stream)request.GetResponse().GetResponseStream();
StreamReader sr = new StreamReader(rs);
string strList = sr.ReadToEnd();
string[] lines = null;
if (strList.Contains("\r\n"))
{
lines = strList.Split(new string[] { "\r\n" }, StringSplitOptions.None);
}
else if (strList.Contains("\n"))
{
lines = strList.Split(new string[] { "\n" }, StringSplitOptions.None);
}
if (lines == null || lines.Length == 0)
return null;
else{
foreach (string line in lines)
{
if (line.Length == 0)
continue;
int x=line.LastIndexOf(' ');
int len = line.Length;
var str = line.Substring( (x+1), (len - x - 1));
var filePath = FtpServerPath+"/"+str;
filePathList.Add(filePath);
}
}
catch (Exception ex)
{
MessageBox.Show("Error: " + ex.Message);
}
}

Tokenizer not separating string? (JAVA)

I have a class Called File
Location which stores the size, name, drive and directory of a file.
The class is supposed to separate the extension from the file name ("java" from "test.java") then compare it to another file using an equals method. Though for some reason it is returning false everytime. Any idea what's wrong?
Class file
import java.util.*;
public class FileLocation
{
private String name;
private char drive;
private String directory;
private int size;
public FileLocation()
{
drive = 'X';
directory = "OOProgramming\\Practicals\\";
name = "test";
size = 2;
}
public FileLocation(char driveIn, String dirIn, String nameIn, int sizeIn)
{
drive = driveIn;
directory = dirIn;
name = nameIn;
size = sizeIn;
}
public String getFullPath()
{
return drive + ":\\" + directory + name;
}
public String getFileType()
{
StringTokenizer st1 = new StringTokenizer(name, ".");
return "File type is " + st1.nextToken();
}
public String getSizeAsString()
{
StringBuilder data = new StringBuilder();
if(size > 1048575)
{
data.append("gb");
}
else if(size > 1024)
{
data.append("mb");
}
else
{
data.append("kb");
}
return size + " " + data;
}
public boolean isTextFile()
{
StringTokenizer st2 = new StringTokenizer(name, ".");
if(st2.nextToken() == ".txt" || st2.nextToken() == ".doc")
{
return true;
}
else
{
return false;
}
}
public void appendDrive()
{
StringBuilder st1 = new StringBuilder(drive);
StringBuilder st2 = new StringBuilder(directory);
StringBuilder combineSb = st1.append(st2);
}
public int countDirectories()
{
StringTokenizer stDir =new StringTokenizer(directory, "//");
return stDir.countTokens();
}
public String toString()
{
return "Drive: " + drive + " Directory: " + directory + " Name: " + name + " Size: " + size;
}
public boolean equals(FileLocation f)
{
return drive == f.drive && directory == f.directory && name == f.name && size == f.size;
}
}
Tester program
import java.util.*;
public class FileLocationTest
{
public static void main(String [] args)
{
Scanner keyboardIn = new Scanner(System.in);
FileLocation javaAssign = new FileLocation('X', "Programming\\Assignment\\", "Loan.txt", 1);
int selector = 0;
System.out.print(javaAssign.isTextFile());
}
}

this code will give true only if the file is doc.
StringTokenizer st2 = new StringTokenizer(name, ".");
if(st2.nextToken() == ".txt" || st2.nextToken() == ".doc")
if file name file.txt then what happend
(st2.nextToken() == ".txt") means ("file" == "txt") false
(st2.nextToken() == ".doc") means ("txt" == "txt") false
first token will gave file name second token will gave ext.
right code is
StringTokenizer st2 = new StringTokenizer(name, ".");
String filename = st2.nextToken();
String ext = st2.nextToken();
if(ext.equalsIgnoreCase(".txt") || ext.equalsIgnoreCase(".txt"))
use always equals to compare strings not ==

Take a look at my own question I posted a while back. I ended up using Apache Lucene's tokenizer.
Here is how you use it (copied from here):
TokenStream tokenStream = analyzer.tokenStream(fieldName, reader);
OffsetAttribute offsetAttribute = tokenStream.addAttribute(OffsetAttribute.class);
CharTermAttribute charTermAttribute = tokenStream.addAttribute(CharTermAttribute.class);
while (tokenStream.incrementToken()) {
int startOffset = offsetAttribute.startOffset();
int endOffset = offsetAttribute.endOffset();
String term = charTermAttribute.toString();
}

Batch rename files while keeping part of the name?

Like the title suggests I want to batch rename files but keep the first 4 characters of the file name.
Trying to modify this open source batchfilerenametool for personal use. Any suggestions?
I added the code that renames the file. Where it says filename = filename + generatedSequence; pretty sure that is where I need to add it, but what would specify just the first 4 characters of the file name?
//this is affected by the RenameOption, if Rename has something then only we RENAME
if(cbxRename.isSelected() == true){
fileName = Rename + generatedSequence; //the fileName will change.
}
else {
//if Rename has nothing, but the txtSequence has some Value, we take it to the naming too
fileName = fileName + generatedSequence;
}
Below is the rename part of the code.
private void renameFile(){
boolean operationResult = false;
boolean overallResult = true;
int failCount = 0;
/* the operation of this part is ensured by the chooseDirectory()
* WE get the list of files in the directory
* get the conditions set by users
* and perform the file rename operation.
*/
//Let's get all the information from user
String[] fileList = directory.list(); //the list of files in the directory
String Prefix = txtPrefix.getText();
String Rename = txtRename.getText();
String Suffix = txtSuffix.getText();
String digits = (String) cboSequence.getSelectedItem();
int StartingNum;
String generatedSequence;
File oldFile;
//let's call the output frame
if(cbxOutput.isSelected() && OUTPUT_ON == false){
buildOutput();
OUTPUT_ON = true;
}
//display the list of files and readability of each file
for(int i = 0; i < fileList.length; i++){
oldFile = new File(directory.getPath()+"/"+ fileList[i]);
String readability = fileList[i] +" - readable?: "+oldFile.canRead();
System.out.println(readability);
if(OUTPUT_ON)
txaOutput.append("\n"+readability);
}
for(int i = 0; i < fileList.length; i++){
/* get the file extension that we need, and form a new name,
* we would check if the Ignore File Extension is selected
*/
oldFile = new File(directory.getPath()+"/"+ fileList[i]);
String fileExtension;
if(cbxIgnoreExtension.isSelected() == true ){
fileExtension = "";
}
else
fileExtension = getFileExtension(fileList[i]);
//this part get the original filename
String fileName = getFileName(fileList[i]);
String inputInfo = "The input filename->"+ fileList[i] + "\nfile name->" + fileName + "\nextension->" + fileExtension;
System.out.println(inputInfo);
if(OUTPUT_ON)
txaOutput.append("\n"+inputInfo);
/* generate sequence for the Name
*if the digits selection is NONE, we ignore it
*/
if(digits.equals("None") == true){
generatedSequence = "";
}
else{
StartingNum = Integer.parseInt(txtSequence.getText());
generatedSequence = nameSequence(StartingNum + i, digits);
}
//this is affected by the RenameOption, if Rename has something then only we RENAME
if(cbxRename.isSelected() == true){
fileName = Rename + generatedSequence; //the fileName will change.
}
else{
//if Rename has nothing, but the txtSequence has some Value, we take it to the naming too
fileName = fileName + generatedSequence;
}
//the New File Name
String newFileName = Prefix + fileName + Suffix + fileExtension;
String tentativeName = "new Filename will be ->"+newFileName+"\n";
System.out.println(tentativeName);
if(OUTPUT_ON)
txaOutput.append("\n"+tentativeName);
// ! Perform the file rename, if the Experimental Mode is not selected
if(cbxExperiment.isSelected() == false){
operationResult = oldFile.renameTo(new File(directory.getPath()+"/"+newFileName));
String renameResult = "\t*Rename successfully?: " + operationResult+"\n\n";
System.out.println(renameResult);
if(operationResult == false)
failCount++;
if(OUTPUT_ON)
txaOutput.append("\n"+renameResult);
//make up the overall result
overallResult = (operationResult && overallResult);
}
}
if(cbxExperiment.isSelected() == false){
System.out.println("Overall Result: "+overallResult);
if(overallResult)
JOptionPane.showMessageDialog(null, "All files renamed successfully!");
else
JOptionPane.showMessageDialog(null, "File renamed with "+ failCount+ " failure(s)");
}//end if
}//end renameFile

Part of String can be selected via String.substring(start, end) method:
filename = filename.substring(0, 4) + generatedSequence;
In general you should not use constant end parameter since original String may be shorter so it is good idea to limit it to length of String:
filename = filename.substring(0, Math.min(4, filename.length())) + generatedSequence;