CODEWITHSUNDEEP
android
Ranjith
Ranjith

Reputation: 309

Issue on appending a file in android

I am creating an android application which reads and writes data to a file in the location /sdcard/ReadandWrite/.when i writing to that file it does not write in append mode.it will removes the old data and writes the new one.please help me to solve this.Here is my code.

private File openfile() {
    File sdCard = Environment.getExternalStorageDirectory();
    File dir = new File (sdCard.getAbsolutePath() + "/ReadandWrite");
    dir.mkdirs();
    File file = new File(dir, "myfile.txt");
    file.setWritable(true);
    if(file.exists())
    {
        file.canRead();
        file.setWritable(true);

    }
    else {
        try {
            file.createNewFile();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    return file;
}

private void writetofile() {


    try {
        File file=openfile();
        OutputStreamWriter myOutWriter =
                new OutputStreamWriter(new FileOutputStream(file));
        myOutWriter.append(text.getText());

        myOutWriter.close();
        myOutWriter.close();
        Toast.makeText(getBaseContext(),
                "Done writing SD 'mysdfile.txt'",
                Toast.LENGTH_SHORT).show();
    } catch (Exception e) {
        Toast.makeText(getBaseContext(), e.getMessage(),
                Toast.LENGTH_SHORT).show();
    }

Upvotes: 4

Views: 61

Answers (1)

Daniel Le
Daniel Le

Reputation: 1840

You need to configure the FileOutputStream to use append mode. From JDK documentation:

public FileOutputStream(String name, boolean append) throws FileNotFoundException

Creates a file output stream to write to the file with the specified name. If the second argument is true, then bytes will be written to the end of the file rather than the beginning. A new FileDescriptor object is created to represent this file connection.

First, if there is a security manager, its checkWrite method is called with name as its argument.

If the file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason then a FileNotFoundException is thrown.

Parameters: name - the system-dependent file name append - if true, then bytes will be written to the end of the file rather than the beginning Throws: FileNotFoundException - if the file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason. SecurityException - if a security manager exists and its checkWrite method denies write access to the file. Since: JDK1.1 See Also: SecurityManager.checkWrite(java.lang.String)

So change OutputStreamWriter myOutWriter = new OutputStreamWriter(new FileOutputStream(file));

to

OutputStreamWriter myOutWriter = new OutputStreamWriter(new FileOutputStream(file, true));

Upvotes: 3

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