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How can I add new information to a .txt file without it removing any old data in java [duplicate]

This question already has answers here:
How to append text to an existing file in Java?
(31 answers)
Closed 2 years ago.
I want to store all the sales in a txt file, but every time I enter new information it deletes the old information. Any idea why?
try {
BufferedWriter bfw = new BufferedWriter(new FileWriter(file1));
BufferedWriter bfw1 = new BufferedWriter(new FileWriter(file2));
bfw.write(Total.getText());
bfw.newLine();
String timeStamp = new SimpleDateFormat("yyyy.MM.dd.HH.mm.ss").format(new java.util.Date());
bfw1.write(timeStamp);
bfw1.newLine();
bfw.close();
bfw1.close();
} catch (IOException ex) {
Logger.getLogger(FrmFacturas.class.getName()).log(Level.SEVERE, null, ex);
}

You can put a second parameter to the FileWriter constructor:
BufferedWriter bfw = new BufferedWriter(new FileWriter(file1, true));
OR
you could use Files.nio:
Files.writeString(file1.toPath(), textToWrite, StandardOpenOption.APPEND)

You have to open the file in append mode to do this add true as the second parameter in FileWriter
BufferedWriter bfw = new BufferedWriter(new FileWriter(file1,true));

Writing File in java with Array List but not working [duplicate]

This question already has answers here:
How do I create a file and write to it?
(35 answers)
Closed 4 years ago.
It seems fine but the the content is not write into file with write() method. I ask the user input with JoptionPane and add that data to ArrayList . The data is added , but when I try to output that data into file, it's not write to file.
public class fileArray {
public static void main(String[] args) throws IOException {
ArrayList al = new ArrayList();
File f =new File("notworking.txt");
String names = " ";
while(!names.isEmpty())
{
names=JOptionPane.showInputDialog("EnterName");
if(!names.isEmpty()){
al.add(names);}
}
FileWriter fw = new FileWriter(f.getAbsoluteFile());
BufferedWriter bw = new BufferedWriter(fw);
int sz= al.size();
for(int i =0;i<sz;i++){
bw.write((String) al.get(i));
System.out.println(al.get(i));
}
}
}

You need to close the writer after you are done with writing.
bw.close();

Either you have to flush or close the buffer afte you write to the file. Better you close the buffer in finally block, make it habit to close the buffer in finally block.

sample code:
PrintWriter writer = new PrintWriter("the-file-name.txt", "UTF-8");
writer.println("The first line");
writer.println("The second line");
writer.close(); // CLOSE

How to load a preexisting PrintWriter into Java? [duplicate]

This question already has answers here:
How to append text to an existing file in Java?
(31 answers)
Java: How to read a text file
(9 answers)
Closed 5 years ago.
I have a txt file that I want to load into Java, and I've been trying to use
PrintWriter writer = new PrintWriter(new File("location/name.txt"));
But instead of loading the existing file, it writes over the old one and creates a new blank one. How can I load the existing file into Java?

You must use a Reader instead of Writer.
There are various ways to read a text file in Java e.g. you can use FileReader, BufferedReader or Scanner to read a text file. Each class has its own purpose e.g. BufferedReader is used to buffer data for reading fast, and Scanner provides parsing ability.
Example using BufferedReader :
public class ReadFile {
public static void main(String[] args)throws Exception
{
File file = new File("C:\\location\\test.txt");
BufferedReader br = new BufferedReader(new FileReader(file));
String st;
while ((st = br.readLine()) != null)
System.out.println(st);
}
}

I think this is what you want:
try(PrintWriter pw = new PrintWriter(new BufferedWriter(new FileWriter("location/yourFileName.txt", true)))) {
pw.println("what you want to write to the file");
pw.close();
} catch (IOException e) {
//Exception handling goes here.
}
The FileWriter constructor's second argument is what sets the append condition. Also, as stated in the comments(and pretty obvious) that you need a reader to load or input data.

You can try
File f = new File(filePathString);

How do you get the text in system.output.println? [duplicate]

This question already has answers here:
How do I create a file and write to it?
(35 answers)
Closed 8 years ago.
On the output part of my IDE (where all the system.out.println textx appear), I have several lines of text. I want to get them and save them to a text file. What would be the possible code for this?

use System#setOut() to redirect output to FileOutputStream to redirect System output to file
// for restore purpose
PrintStream oldOutStream = System.out;
PrintStream outFile = new PrintStream(
new FileOutputStream("/path/to/file.txt", true));
System.setOut(outFile);
System.out.println("this will goto file");
I assume you know about logging framework and you are not trying to use this for logging something

Yo can replce all sop with fileoutput strem and write everything in file
if you want to write log then you can use log4j
String content = "This is the content to write into file";
File file = new File("filename.txt");
// if file doesnt exists, then create it
if (!file.exists()) {
file.createNewFile();
}
FileWriter fw = new FileWriter(file.getAbsoluteFile());
BufferedWriter bw = new BufferedWriter(fw);
bw.write(content);
bw.close();

Printwriter how not to overwrite [duplicate]

This question already has answers here:
PrintWriter append method not appending
(5 answers)
Closed 9 years ago.
So I got this piece of code in my Java program;
String filename = "direct.txt";
String s = fil.getAbsolutePath();
Process p = Runtime.getRuntime().exec(s);
try
{
PrintWriter outputStream = new PrintWriter(filename);
outputStream.println(s);
outputStream.close();
}
catch (FileNotFoundException e1) {e1.printStackTrace();};
But when it writes to the file, it overwrites it when it writes something new, how can I make it so it doesn't overwrite but instead goes to the next line and prints it there?

You could make a FileWriter object and pass it as an argument when making the PrintWriter object. That way if the file already exists then it won't be overwritten, but if it does not exist then it will be created. From there you can use the PrintWriter methods as normal:
FileWriter objectName = new FileWriter("filename", true);
PrintWriter outputStream = new PrintWriter(objectName);