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How can I add a code that prints when record is deleted successfully or invalid if they enter other number not in txt file?

Any idea on How I can check if A record is deleted or is there a better way to delete an array of code using bufferedreader and writter?
public static void DeleteData() throws IOException {
try {
Viewrecord();
Scanner strInput = new Scanner(System.in);
String ID, record;
File tempDB = new File("tempdata.txt");
File db = new File("Database.txt");
BufferedReader br = new BufferedReader(new FileReader(db));
BufferedWriter bw = new BufferedWriter(new FileWriter(tempDB));
System.out.println("\t\t Delete An Item \n");
System.out.println("Enter Item ID: ");
ID = strInput.nextLine();
while ((record = br.readLine()) != null) {
String[] data = record.split(":::");
if (data[0].toString().equals(ID))
continue;
{
bw.write(record);
bw.flush();
bw.newLine();
}
}
br.close();
bw.close();
db.delete();
tempDB.renameTo(db);
} catch (IOException ex) {
System.out.println(ex.toString());
}
}
I did try using a boolean inside the while loop

Java append new column to csv file

I want to calculate some column data and write it to csv file as column. Then after calculating other column of data I want to append it to same file but as new column.
Here is what I did:
try {
FileWriter writer = new FileWriter(OUT_FILE_PATH, true);
for (int i=0; i<data.size(); i++) {
writer.append(String.valueOf(data.get(i)));
writer.append(",");
writer.append("\n");
}
writer.flush();
writer.close();
} catch (Exception e) {}
Result - It appends the new column below the first column, so I have single long column.
Thanks,

Something like this perhaps:
public void appendCol(String fileName, ???ArrayList??? data) { //assuming data is of type ArrayList here, you need to be more explicit when posting code
String lineSep = System.getProperty("line.separator");
String output = "";
try{
BufferedReader br = new BufferedReader(new FileReader(fileName));
String line = null;
int i = 0;
while ((line = br.readLine()) != null) {
output += line.replace(
lineSep,
"," + String.valueOf(data.get(i)) + lineSep);
i++;
}
br.close();
FileWriter fw = new FileWriter(fileName, false); //false to replace file contents, your code has true for append to file contents
fw.write(output);
fw.flush();
fw.close();
} catch (Exception e){
e.printStackTrace();
}
}

You will have to read your file (line by line) and then insert the new column to every line. Here's a solution using BufferedReader and BufferedWriter
public void addColumn(String path,String fileName) throws IOException{
BufferedReader br=null;
BufferedWriter bw=null;
final String lineSep=System.getProperty("line.separator");
try {
File file = new File(path, fileName);
File file2 = new File(path, fileName+".1");//so the
//names don't conflict or just use different folders
br = new BufferedReader(new InputStreamReader(new FileInputStream(file))) ;
bw = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file2)));
String line = null;
int i=0;
for ( line = br.readLine(); line != null; line = br.readLine(),i++)
{
String addedColumn = String.valueOf(data.get(i));
bw.write(line+addedColumn+lineSep);
}
}catch(Exception e){
System.out.println(e);
}finally {
if(br!=null)
br.close();
if(bw!=null)
bw.close();
}
}

I have used apache-commons for resolving this issue. There was no perfect answer that worked for me. After a lot of effort, this worked for me.
Writer writer = Files.newBufferedWriter(Paths.get("output.csv"));
CSVPrinter csvPrinter = new CSVPrinter(writer, CSVFormat.DEFAULT
//add whichever column you want in withHeader
.withHeader("createdTs", "destroyedTs", "channelName", "uid", "suid", "did", "joinTs", "leaveTs", "platform", "location", "consumption"));
//actual columns in your passed CSV
String[] HEADERS = {"createdTs", "destroyedTs", "channelName", "uid", "suid", "did", "joinTs", "leaveTs", "platform", "location"};
Reader in = new FileReader(yourCsvFile);
Iterable<CSVRecord> records = CSVFormat.DEFAULT
.withHeader(HEADERS)
.withFirstRecordAsHeader()
.parse(in);
for (CSVRecord row : records) {
String tempValue = String.valueOf(Long.parseLong(row.get("leaveTs")) - Long.parseLong(row.get("joinTs")));
csvPrinter.printRecord(row.get("createdTs"), row.get("destroyedTs"),row.get("channelName"), row.get("uid"),
row.get("suid"), row.get("did"), row.get("joinTs"), row.get("leaveTs"),
row.get("platform"), row.get("location"), tempValue);
}

Hope this will help you.
{
//CREATE CSV FILE
StringBuffer csvReport = new StringBuffer();
csvReport.append("header1,Header2,Header3\n");
csvReport.append(value1 + "," + value2 + "," + value3 + "\n");
generateCSVFile( filepath,fileName, csvReport); // Call the implemented mathod
}
public void generateCSVFile(String filepath,String fileName,StringBuffer result)
{
try{
FileOutputStream fop = new FileOutputStream(filepath);
// get the content in bytes
byte[] contentInBytes = result.toString().getBytes();
fop.write(contentInBytes);
fop.flush();
//wb.write(fileOut);
if(fop != null)
fop.close();
}catch (Exception ex)
{
ex.printStackTrace();
}
}

Deleting File and Renaming file in java

i am trying to use this code to replace field and after the replace is done i like to delete the file. But when i replace the file only 1 line was saved. How should i ensure that the other lines will be saved?
public static void main(String[] args){
AddChips();
}
public static void AddChips() {
File oldFile = new File ("players.dat");
File newFile = new File ("tempchips.dat");
BufferedReader br = null;
BufferedWriter bw = null;
ArrayList<String> player = new ArrayList<String>();
try {
br = new BufferedReader(new FileReader(oldFile));
bw = new BufferedWriter(new FileWriter(newFile));
String line;
Scanner read = new Scanner(System.in);
System.out.println("Please Enter Username");
String UserN = read.nextLine();
System.out.println("Please Enter Chips to Add");
String UserCadd = read.nextLine();
while ((line = br.readLine()) != null) {
String[] details = line.split("\\|");
String Username = details[0];
String Password = details[1];
String Chips = details[2];
int totalChips = (Integer.parseInt(UserCadd)+ Integer.parseInt(Chips));
if (Username.equals(UserN)){
line = Username + "|" + Password + "|" + totalChips;
bw.write(line + System.getProperty("line.separator"));
}
//issue is here
br.close();
bw.close();
oldFile.delete();
newFile.renameTo(oldFile);
//AdminMenu();
}
} catch (Exception e) {
return;
} finally {
try {
if(br != null)
br.close();
} catch (IOException e) {
//
}
try {
if(bw != null)
bw.close();
} catch (IOException e) {
//
}
}
}

How can i split a textfile and store 2 values in one line?

I have a text file -> 23/34 <- and I'm working on a Java program.
I want to store them out in String One = 23 and anotherString = 34 and put them together to one string to write them down in a text file, but it dosen't work. :( Everytime it makes a break. Maybe because the split method but I don't know how to separate them.
try {
BufferedReader in = new BufferedReader (new FileReader (textfile) );
try {
while( (textfile= in.readLine()) != null ) {
String[] parts = textfileString.split("/");
String one = parts[0];
}
}
}
When I print or store one + "/" + anotherString, it makes a line-break at one but I want it all in one line. :(

public static void main(String[] args) throws Exception {
File file = new File("output.txt");
if (!file.exists()) {
file.createNewFile();
}
BufferedWriter bw = new BufferedWriter(new FileWriter(file.getAbsoluteFile()));
BufferedReader br = new BufferedReader(new FileReader("input.txt"));
String line = null;
while ((line = br.readLine()) != null) {
String string1 = line.split("/")[0];
String string2 = line.split("/")[1];
bw.write(string1 + string2 + "\n");
bw.flush();
}
br.close();
bw.close();
}
On file:
23/34
Resulted in output.txt containing:
2334
You need to read in each line, and split it on your designated character ("/"). Then assign string1 to the first split, and string2 to the second split. You can then do with the variables as you want. To output them to a file, you simply append them together with a + operator.

You have never shown us how you are writing the file, so we can't really help you with your code. This is a bit of a more modern approach, but I think it does what you want.
File infile = new File("input.txt");
File outfile = new File("output.txt");
try (BufferedReader reader = Files.newBufferedReader(infile.toPath());
BufferedWriter writer = Files.newBufferedWriter(outfile.toPath())) {
String line;
while ((line = reader.readLine()) != null) {
String parts[] = line.split("/");
String one = parts[0];
String two = parts[1];
writer.write(one + "/" + two);
}
} catch (IOException ex) {
System.err.println(ex.getLocalizedMessage());
}

InputStream stream = this.getClass().getResourceAsStream("./test.txt");
BufferedReader reader = new BufferedReader(new InputStreamReader(stream));
String currentLine;
try {
while ((currentLine = reader.readLine()) != null) {
String[] parts = currentLine.split("/");
System.out.println(parts[0] + "/" + parts[1]);
}
} catch (IOException e) {
e.printStackTrace();
} finally{
try {
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
}

Text File error Scanner

I'm writing code which deletes a word out of a text file when the user inputs it but I cant seem to get the scanner part to work
public static void Option2Method() throws IOException
{
File inputFile = new File("wordlist.txt");
File tempFile = new File("TempWordlist.txt");
String lineToRemove = JOptionPane.showInputDialog(null, "Enter a word to remove");
Scanner reader = new Scanner(inputFile);
Scanner writer =new Scanner(tempFile);
String currentLine;
while((currentLine = reader.nextLine()) != null)
{
String trimmedLine = currentLine.trim();
if(trimmedLine.equals(lineToRemove)) continue;
writer.print(currentLine + "\n");
}
reader.close();
writer.close();
inputFile.delete();
tempFile.renameTo(inputFile);
}

Scanner is not meant to write files, hence does not have a write() method. You can use BufferedWriterinstead.
Example:
public static void Option2Method() throws IOException {
File inputFile = new File("wordlist.txt");
FileWriter fstream = new FileWriter("TempWordlist.txt", true);
BufferedWriter writer = new BufferedWriter(fstream);
File tempFile = new File("TempWordlist.txt");
String lineToRemove = JOptionPane.showInputDialog(null, "Enter a word to remove");
Scanner reader = new Scanner(inputFile);
while (reader.hasNextLine()) {
String trimmedLine = reader.nextLine().trim();
if (trimmedLine.equals(lineToRemove))
continue;
writer.write(trimmedLine + "\n");
}
reader.close();
writer.close();
inputFile.delete();
tempFile.renameTo(inputFile);
}
Using PrintWriter:
File inputFile = new File("wordlist.txt");
PrintWriter writer = new PrintWriter(new BufferedWriter(new FileWriter("TempWordlist.txt", true)));
File tempFile = new File("TempWordlist.txt");
String lineToRemove = JOptionPane.showInputDialog(null, "Enter a word to remove");
Scanner reader = new Scanner(inputFile);
while (reader.hasNextLine()) {
String trimmedLine = reader.nextLine().trim();
if (trimmedLine.equals(lineToRemove))
continue;
writer.print(trimmedLine + "\n");
}
reader.close();
writer.close();
inputFile.delete();
tempFile.renameTo(inputFile);

Scanner doesn't have a print method. It is used to scan a file and read data from it.
If you want to write to a file, use this or that or just google "java write to file"