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Rename the file if exists instead of overwriting it

When I execute below code it overwrite the existing file. I want to keep old file and new file too. What can be done here? Can we rename it like Test(1).xlsx, Test(2).xlsx, Test(3).xlsx like windows pattern?
File excel = new File("C:\\TEST\\Test.xlsx");
try (FileInputStream fis = new FileInputStream(excel);
XSSFWorkbook book = new XSSFWorkbook(fis);) {
..
..
..
try (FileOutputStream outputStream = new FileOutputStream("C:\\TEST\\Output\\Test.xlsx")) {
book.write(outputStream);
}
}

You can check if the file already exists using the exists() method before you start writing to it.
If the file already exists, write to a different file.
File excel = new File(determineFileName());
try (FileInputStream fis = new FileInputStream(excel);
XSSFWorkbook book = new XSSFWorkbook(fis);) {
...
}
with
private String determineFileName(){
String path = "C:\\TEST\\Test.xlsx";
int counter = 0;
while(new File(path).exists()){
counter++;
path = "C:\\TEST\\Test(" + counter + ").xlsx";
}
return path;
}

Sub Directories under getCacheDir()

I'm trying to create sub directories in my apps cache folder but when trying to retrieve the files I'm getting nothing. I have some code below on how I created the sub directory and how I'm reading from it, maybe I'm just doing something wrong (well clearly I am lol) or maybe this isn't possible? (though I haven't seen anywhere that you can't). thank you all for any help!
creating the sub dir
File file = new File(getApplicationContext().getCacheDir(), "SubDir");
File file2 = new File(file, each_filename);
Toast.makeText(getApplicationContext(), file2.toString(), Toast.LENGTH_SHORT).show();
stream = new FileOutputStream(file2);
stream.write(bytes);
reading from it
File file = new File(context.getCacheDir(), "SubDir");
File newFile = new File(file, filename);
Note note;
if (newFile.exists()) {
FileInputStream fis;
ObjectInputStream ois;
try {
fis = new FileInputStream(new File(file, filename));
ois = new ObjectInputStream(fis);
note = (Note) ois.readObject();
fis.close();
ois.close();
} catch (IOException | ClassNotFoundException e) {
e.printStackTrace();
return null;
}
return note;
}
I've also tried with this and nothing
String file = context.getCacheDir() + File.separator + "SubDir";

I don't see anywhere in the code you posted where you actually create the sub-directory. Here's some example code to save a file in a sub-directory, by calling mkdirs if the path doesn't yet exist (some parts here need to be wrapped in an appropriate try-catch for an IOException, but this should get you started).
File cachePath = new File(context.getCacheDir(), "SubDir");
String filename = "test.jpeg";
boolean errs = false;
if( !cachePath.exists() ) {
// mkdir would work here too if your path is 1-deep or
// you know all the parent directories will always exist
errs = !cachePath.mkdirs();
}
if(!errs) {
FileOutputStream fout = new FileOutputStream(cachePath + "/" + filename);
fout.write(bytes.toByteArray());
fout.flush();
fout.close();
}

You need to make your directory with mkdir.
In your code:
File file = new File(getApplicationContext().getCacheDir(), "SubDir");
file.mkdir();
File file2 = new File(file, each_filename);

Deleting PDF file after printing in Java

I'm trying to delete a PDF file after printing. The PDF is generated using JAVA code and needs to be deleted after the printing process is carried out. However, I am facing an issue while deleting the file. I can't seem to figure out what the problem is.
The error shown while trying to delete the file from its folder is:
"File in Use: The Action can't be completed because the file is open in Java(TM) Platform SE Binary."
The code I've used is as follows:
public String actionPrintReport() {
try {
// Creates a new document object
Document document = new Document(PageSize.LETTER);
File file = new File(fileLocation.concat("\\".concat(fileName)));
FileOutputStream fo = new FileOutputStream(file);
// Creates a pdfWriter object for the FILE
PdfWriter pdfWriter = PdfWriter.getInstance(document, fo);
// Open the document
document.open();
// Add meta data...
// Insert Data...
// Close the document
document.close();
// Create a PDFFile from a File reference
FileInputStream fis = new FileInputStream(file);
FileChannel fc = fis.getChannel();
ByteBuffer bb = fc.map(FileChannel.MapMode.READ_ONLY, 0, fc.size());
PDFFile pdfFile = new PDFFile(bb);
// Create PDF Print Page
PDFPrintPage pages = new PDFPrintPage(pdfFile);
// Create Print Job...
// Close
fo.flush();
fo.close();
fis.close();
if (file.exists()) {
if (file.delete()) {
String check = "yes";
} else {
String check = "no";
}
}
// Send print job to default printer
pjob.print();
actionMsg = "success";
return SUCCESS;
} catch (Exception e) {
e.printStackTrace();
}
return ERROR;
}

why not put the deletion in a finally block?
} catch (Exception e) {
e.printStackTrace();
} finally {
if (file.exists()) {
file.delete();
}
}
After discussion with the OP, an approach was investigated to use Apache FileCleaningTracker whereby the File is tracked and then deleted after a Monitored Object has been GC'd.

java how to check if file exists and open it?

how to check if file exists and open it?
if(file is found)
{
FileInputStream file = new FileInputStream("file");
}

File.isFile will tell you that a file exists and is not a directory.
Note, that the file could be deleted between your check and your attempt to open it, and that method does not check that the current user has read permissions.
File f = new File("file");
if (f.isFile() && f.canRead()) {
try {
// Open the stream.
FileInputStream in = new FileInputStream(f);
// To read chars from it, use new InputStreamReader
// and specify the encoding.
try {
// Do something with in.
} finally {
in.close();
}
} catch (IOException ex) {
// Appropriate error handling here.
}
}

You need to create a File object first, then use its exists() method to check. That file object can then be passed into the FileInputStream constructor.
File file = new File("file");
if (file.exists()) {
FileInputStream fileInputStream = new FileInputStream(file);
}

You can find the exists method in the documentation:
File file = new File(yourPath);
if(file.exists())
FileInputStream file = new FileInputStream(file);

File Path appearing in the Zipped File

I have a java program as below for zipping a folder as a whole.
public static void zipDir(String dir2zip, ZipOutputStream zos)
{
try
{
File zipDir= new File(dir2zip);
String[] dirList = zipDir.list();
byte[] readBuffer = new byte[2156];
int bytesIn = 0;
for(int i=0; i<dirList.length; i++)
{
File f = new File(zipDir, dirList[i]);
if(f.isDirectory())
{
String filePath = f.getPath();
zipDir(filePath, zos);
continue;
}
FileInputStream fis = new FileInputStream(f);
ZipEntry anEntry = new ZipEntry(f.getPath());
zos.putNextEntry(anEntry);
while((bytesIn = fis.read(readBuffer)) != -1)
{
zos.write(readBuffer, 0, bytesIn);
}
fis.close();
}
}
catch(Exception e)
{
e.printStackTrace();
}
}
public static void main(){
String date=new java.text.SimpleDateFormat("MM-dd-yyyy").format(new java.util.Date());
ZipOutputStream zos = new ZipOutputStream(new FileOutputStream("Output/" + date + "_RB" + ".zip"));
zipDir("Output/" + date + "_RB", zos);
zos.close();
}
My query here is. The target folder(+date+_RB) to be zipped is present inside the folder named Output. After successful zipping, when I extract the zipped file, I find a folder Output inside which the (+date+_RB) required folder is present. I need not want that Output folder after the extraction of the zipped file, rather it should directly extract the required folder alone. Please advise on the same.
UPDATE:
I tried Isaac's answer. While extracting the resultant zip file, no folders are getting extracted. Only the files inside all the folders are getting extracted. I just dont need the folder "Output" alone in the resultant zip file. But what the program does is, it doesnt extracts all other folders inside the Output folder, rather it just extracts the files inside those folders. Kindly advise on how to proceed...

It happens because of this:
ZipEntry anEntry = new ZipEntry(f.getPath());
f.getPath() will return Output/ at the beginning of the string. This is due to the flow of your program and how it (mis)uses File objects.
I suggest you construct a File object called, say, tmp:
File tmp = new File(dirList[i]);
The change the construction of f:
File f = new File(zipDir, tmp.getPath());
Then, change this:
ZipEntry anEntry = new ZipEntry(f.getPath());
To this:
ZipEntry anEntry = new ZipEntry(tmp.getPath());
I didn't have time to actually test it, but in a nutshell, your problem is due to how the File object is constructed.