I am new to Java and trying to save a multi line string to a text file.
Right now, it does work within my application. Like, if I save the file from my application and then open it from my application, it does put a space between lines. However, if I save the file from my app and then open it in Notepad, it is all on one line.
Is there a way to make it show multi line on all programs? Here's my current code:
public static void saveFile(String contents) {
// Get where the person wants to save the file
JFileChooser fc = new JFileChooser();
int rval = fc.showSaveDialog(fc);
if(rval == JFileChooser.APPROVE_OPTION) {
File file = fc.getSelectedFile();
try {
//File out_file = new File(file);
BufferedWriter out = new BufferedWriter(new FileWriter(file));
out.write(contents);
out.flush();
out.close();
} catch(IOException e) {
messageUtilities.errorMessage("There was an error saving your file. IOException was thrown.", "File Error");
}
}
else {
// Do nothing
System.out.println("The user choose not to save anything");
}
}
depending on how you are constructing your string, you may just be running into a line ending problem. Notepad does not support unix line endings (\n only) it only supports windows line endings (\n\r). try opening your saved file using a more robust editor, and/or make sure you are using the proper line endings for your platform. java's system property (System.getProperty("line.separator")) will get you the proper line ending for the platform that the code is running on.
while you're building your string to be saved to the file, rather than explicitly specifying "\n" or "\n\r" (or on the mac "\r") for your line endings, you would instead append the value of that system property.
like so:
String eol = System.getProperty("line.separator");
... somewhere else in your code ...
String texttosave = "Here is a line of text." + eol;
... more code.. optionally adding lines of text .....
// call your save file method
saveFile(texttosave);
Yea as the previous answer mentions the System.getProperty("line.seperator").
your code doesn't show how you created String contents but since you said you were new to java I thought i'd mention that in java concatenating Strings is not nice since it creates a. If you are building the String by doing this:
String contents = ""
contents = contents + "sometext" + "some more text\n"
Then consider using java.lang.StrinBuilder instead
StringBuilder strBuilder = new StringBuilder();
strBuilder.append("sometext").append("somre more text\n");
...
String contents = strBuilder.toString();
Another alternative is to stream what ever your planning to write to a file rather than building a large string and then outputting that.
You could add something like:
contents = contents.replaceAll("\\n","\\n\\r");
if notepad does not display correctly. However you might run into a different problem: at each save/load you will get multiple \r chars. Then to avoid that at load you would have to call the same code above but with reversed parameters. This is really an ugly solution just to get the text to display properly in notepad.
I had this same problem my guy friend, after much thought and research I even found a solution.
You can use the ArrayList to put all the contents of the TextArea for exemple, and send as parameter by calling the save, as the writer just wrote string lines, then we use the "for" line by line to write our ArrayList in the end we will be content TextArea in txt file.
if something does not make sense, I'm sorry is google translator and I who do not speak English.
Watch the Windows Notepad, it does not always jump lines, and shows all in one line, use Wordpad ok.
private void SaveActionPerformed(java.awt.event.ActionEvent evt) {
String NameFile = Name.getText();
ArrayList< String > Text = new ArrayList< String >();
Text.add(TextArea.getText());
SaveFile(NameFile, Text);
}
public void SaveFile(String name, ArrayList< String> message) {
path = "C:\\Users\\Paulo Brito\\Desktop\\" + name + ".txt";
File file1 = new File(path);
try {
if (!file1.exists()) {
file1.createNewFile();
}
File[] files = file1.listFiles();
FileWriter fw = new FileWriter(file1, true);
BufferedWriter bw = new BufferedWriter(fw);
for (int i = 0; i < message.size(); i++) {
bw.write(message.get(i));
bw.newLine();
}
bw.close();
fw.close();
FileReader fr = new FileReader(file1);
BufferedReader br = new BufferedReader(fr);
fw = new FileWriter(file1, true);
bw = new BufferedWriter(fw);
while (br.ready()) {
String line = br.readLine();
System.out.println(line);
bw.write(line);
bw.newLine();
}
br.close();
fr.close();
} catch (IOException ex) {
ex.printStackTrace();
JOptionPane.showMessageDialog(null, "Error in" + ex);
}
Related
I am trying to write an array of string into the external storage of Android emulator. Here is my code:
private void writeToFile(String[] data) {
File workingDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS + "/wordlist.txt");
try (BufferedWriter bw = new BufferedWriter(new FileWriter(workingDir))) {
for (String line : data) {
bw.write(line + "\n");
}
bw.close();
} catch (IOException e) {
e.printStackTrace();
}
}
It did managed to write each of the item in string array into the text file. However, the next time when I execute this function again, it wipes all the previous existing strings in the text file and replaced them instead. Any ideas on how to keep append new strings to the end of the file?
Thanks!
I solved it already. Basically I need to read all the existing text from the text file, add them to a new list, then append the latest string onto the new list, then proceed to write to the text file.
You can use the append option to append to the existing file without overwriting it.
BufferedWriter bw = new BufferedWriter(new FileWriter(workingDir, true))
The optional true argument sets the file writer to append mode. Also see the answers here.
Simply trying to move to a new line after printing each element inside of notepad. Some searching has yielded uses of \r\n, but that doesn't seem to work either.
for(String element : misspelledWords)
{
writer.write(element + "\n");
}
try this
BufferedWriter writer = new BufferedWriter(new FileWriter("result.txt"));
for (String element : misspelledWords) {
writer.write(element);
writer.newLine();
}
Adding line separator at the end (like "\n") should work on most OS,but to be on safer side
you should use System.getProperty("line.separator")
Open your file in append mode like this
FileWriter(String fileName, boolean append) when you want to make an object of class FileWrite
in constructor.
File file = new File("C:\\Users\\Izak\\Documents\\NetBeansProjects\\addNewLinetoTxtFile\\src\\addnewlinetotxtfile\\a.txt");
try (Writer newLine = new BufferedWriter(new FileWriter(file, true));) {
newLine.write("New Line!");
newLine.write(System.getProperty( "line.separator" ));
} catch (IOException e) {
}
Note:
"line.separator" is a Sequence used by operating system to separate lines
in text files
source:
http://docs.oracle.com/javase/tutorial/essential/environment/sysprop.html
I know this is very basic stuff but for some reason I'm having problems with a bufferedReader/ Writer. I am trying to get the first line of text and return it to another method. However, for some reason the writer doesn't seem to be writing to the temp file and it isn't changing the name of the temp file either.
By throwing a few print statements I have been able to figure out:
The while loop is operating correctly
The if else statement is operating correctly
The tempFile is not writing to a text file correctly
The tempFile is not renaming correctly
There are no errors being thrown
private static String wavFinder() throws IOException{
String currentWav=null;
int x = 1;
File inputFile = new File("C:\\convoLists/unTranscribed.txt");
File tempFile = new File("C:\\convoLists/unTranscribedtemp.txt");
BufferedReader reader = new BufferedReader(new FileReader(inputFile));
BufferedWriter writer = new BufferedWriter(new FileWriter(tempFile));
String currentLine = null;
while((currentLine = reader.readLine()) != null) {
if(x == 1){
currentWav = currentLine;
}
else{
writer.write(currentLine);
}
x = 2;
}
boolean successful = tempFile.renameTo(inputFile);
System.out.println("Success: " + successful);
System.out.println("currentWav = " + currentWav);
return currentWav;
}
Here is the method I am using. If you notice anything please let me know and if you have any questions I will be sure to answer them quickly. Thank you :)
First flush the steam(writer) and close them.
You can not have two files with same name. You are trying to rename the temp file with input file. You need to delete input file and then rename it to that.
reader.close();
writer.flush();
writer.close();
inputFile.delete();
Add these lines before rename and it will work
Close your buffers before trying to call renameTo.
reader.close()
writer.close()
File inputFile = new File("C:\convoLists/unTranscribed.txt");
File tempFile = new File("C:\convoLists/unTranscribedtemp.txt");
Why you have different signs for path?
Always should be //.
I have a string that contains new lines. I send this string to a function to write the String to a text file as:
public static void writeResult(String writeFileName, String text)
{
try
{
FileWriter fileWriter = new FileWriter(writeFileName);
BufferedWriter bufferedWriter = new BufferedWriter(fileWriter);
bufferedWriter.write(text);
// Always close files.
bufferedWriter.close();
}
catch(IOException ex) {
System.out.println("Error writing to file '"+ writeFileName + "'");}
} //end writeResult function
But when I open the file, I find it without any new lines.
When I display the text in the console screen, it is displayed with new lines. How can I write the new line character in the text file.
EDIT:
Assume this is the argument text that I sent to the function above:
I returned from the city about three o'clock on that
may afternoon pretty well disgusted with life.
I had been three months in the old country, and was
How to write this string as it is (with new lines) in the text file. My function write the string in one line. Can you provide me with a way to write the text to the file including new lines ?
EDIT 2:
The text is originally in a .txt file. I read the text using:
while((line = bufferedReader.readLine()) != null)
{
sb.append(line); //append the lines to the string
sb.append('\n'); //append new line
} //end while
where sb is a StringBuffer
In EDIT 2:
while((line = bufferedReader.readLine()) != null)
{
sb.append(line); //append the lines to the string
sb.append('\n'); //append new line
} //end while
you are reading the text file, and appending a newline to it. Don't append newline, which will not show a newline in some simple-minded Windows editors like Notepad. Instead append the OS-specific line separator string using:
sb.append(System.lineSeparator()); (for Java 1.7 and 1.8)
or
sb.append(System.getProperty("line.separator")); (Java 1.6 and below)
Alternatively, later you can use String.replaceAll() to replace "\n" in the string built in the StringBuffer with the OS-specific newline character:
String updatedText = text.replaceAll("\n", System.lineSeparator())
but it would be more efficient to append it while you are building the string, than append '\n' and replace it later.
Finally, as a developer, if you are using notepad for viewing or editing files, you should drop it, as there are far more capable tools like Notepad++, or your favorite Java IDE.
SIMPLE SOLUTION
File file = new File("F:/ABC.TXT");
FileWriter fileWriter = new FileWriter(file,true);
filewriter.write("\r\n");
The BufferedWriter class offers a newLine() method. Using this will ensure platform independence.
bufferedWriter.write(text + "\n"); This method can work, but the new line character can be different between platforms, so alternatively, you can use this method:
bufferedWriter.write(text);
bufferedWriter.newline();
Split the string in to string array and write using above method (I assume your text contains \n to get new line)
String[] test = test.split("\n");
and the inside a loop
bufferedWriter.write(test[i]);
bufferedWriter.newline();
This approach always works for me:
String newLine = System.getProperty("line.separator");
String textInNewLine = "this is my first line " + newLine + "this is my second
line ";
Put this code wherever you want to insert a new line:
bufferedWriter.newLine();
PrintWriter out = null; // for writting in file
String newLine = System.getProperty("line.separator"); // taking new line
out.print("1st Line"+newLine); // print with new line
out.print("2n Line"+newLine); // print with new line
out.close();
Here is a snippet that gets the default newline character for the current platform.
Use
System.getProperty("os.name") and
System.getProperty("os.version").
Example:
public static String getSystemNewline(){
String eol = null;
String os = System.getProperty("os.name").toLowerCase();
if(os.contains("mac"){
int v = Integer.parseInt(System.getProperty("os.version"));
eol = (v <= 9 ? "\r" : "\n");
}
if(os.contains("nix"))
eol = "\n";
if(os.contains("win"))
eol = "\r\n";
return eol;
}
Where eol is the newline
so I'm designing a text editor. For the Open/Save methods, I'm trying to use a TextArea (it doesn't have to be one, it's just my current method). Now, I have two problems right now:
1) When I load a file, it currently doesn't remove the contents currently in the text editor. For example, if I typed in "Owl", then loaded a file that contained "Rat", it would end up as "OwlRat". To solve this, I plan to use the replaceRange method (again however, it isn't absolute, any suggestions would be great!). However, I must replace all the contents of the text editor, not just selected text, and I can't figure out how to do that. Any tips?
2) Currently, when I load a file, nothing will happen unless I saved that file the same time I ran the application. So, for example, running the program, saving a file, closing the program, running the program again, and then loading the file will give nothing. I know this is because the String x doesn't carry over, but I can't think of anyway to fix it. Somebody suggested Vectors, but I don't see how they would help...
Here is the code for the Open/Save methods:
Open:
public void Open(String name){
File textFile = new File(name + ".txt.");
BufferedReader reader = null;
try
{
textArea.append(x);
reader = new BufferedReader( new FileReader( textFile));
reader.read();
}
catch ( IOException e)
{
}
finally
{
try
{
if (reader != null)
reader.close();
}
catch (IOException e)
{
}
}
}
Save:
public void Save(String name){
File textFile = new File(name + ".txt");
BufferedWriter writer = null;
try
{
writer = new BufferedWriter( new FileWriter(textFile));
writer.write(name);
x = textArea.getText();
}
catch ( IOException e)
{
}
finally
{
try
{
if ( writer != null)
writer.close( );
}
catch ( IOException e)
{
}
}
}
I had this same problem my guy friend, after much thought and research I even found a solution.
You can use the ArrayList to put all the contents of the TextArea and send as parameter by calling the save, as the writer just wrote string lines, then we use the "for" line by line to write our ArrayList in the end we will be content TextArea in txt file.
if something does not make sense, I'm sorry is google translator and I who do not speak English.
Watch the Windows Notepad, it does not always jump lines, and shows all in one line, use Wordpad ok.
private void SaveActionPerformed(java.awt.event.ActionEvent evt) {
String NameFile = Name.getText();
ArrayList< String > Text = new ArrayList< String >();
Text.add(TextArea.getText());
SaveFile(NameFile, Text);
}
public void SaveFile(String name, ArrayList< String> message) {
path = "C:\\Users\\Paulo Brito\\Desktop\\" + name + ".txt";
File file1 = new File(path);
try {
if (!file1.exists()) {
file1.createNewFile();
}
File[] files = file1.listFiles();
FileWriter fw = new FileWriter(file1, true);
BufferedWriter bw = new BufferedWriter(fw);
for (int i = 0; i < message.size(); i++) {
bw.write(message.get(i));
bw.newLine();
}
bw.close();
fw.close();
FileReader fr = new FileReader(file1);
BufferedReader br = new BufferedReader(fr);
fw = new FileWriter(file1, true);
bw = new BufferedWriter(fw);
while (br.ready()) {
String line = br.readLine();
System.out.println(line);
bw.write(line);
bw.newLine();
}
br.close();
fr.close();
} catch (IOException ex) {
ex.printStackTrace();
JOptionPane.showMessageDialog(null, "Error in" + ex);
}
There's a lot going on here...
What is 'x' (hint: it's not anything from the file!), and why are you appending it to the text area?
BufferedReader.read() returns one character, which is probably not what you're expecting. Try looping across readline().
Follow Dave Newton's advice to handle your exceptions and provide better names for your variables.
The text file will persist across multiple invocation of your program, so the lack of data has nothing to do with that.
Good luck.
Use textArea.setText(TEXT); rather than append; append means to add on to, so when you append text to a TextArea, you add that text to it. setText on the other hand will set the text, replacing the old text with the new one (which is what you want).
As far as why it's failing to read, you are not reading correctly. First of all, .read() just reads a single character (not what you want). Second, you don't appear to do anything with the returned results. Go somewhere (like here) to find out how to read the file properly, then take the returned string and do textArea.setText(readString);.
And like the others said, use e.printStackTrace(); in all of your catch blocks to make the error actually show up in your console.