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How to duplicate a file given a different name in the same directory in windows

I have been trying to duplicate a file but change the name of it in the same windows directory but I got not luck.
I cant just copy the file in the same directory because of the windows rule that two files cannot have the same name in the same directory.
I am not allowed to copy it to another directory then rename it, and then move it back in the same directory.
And I don't see any helpful implementation in the File.class.
Tried something like that but it didnt work:
File file = new File(filePath);
File copiedFile = new File(filePath);
//then rename the copiedFile and then try to copy it
Files.copy(file, copiedFile);

An initial attempt would be using Path as suitable:
Path file = Paths.get(filePath);
String name = file.getFileName().toString();
String copiedName = name.replaceFirst("(\\.[^\\.]*)?$", "-copy$0");
Path copiedFile = file.resolveSibling(copiedName);
try {
Files.copy(file, copiedFile);
} catch (IOException ex) {
Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
}

You could create a new file in the same directory and then just copy the contents of the original file to the duplicate
See: Java read from one file and write into another file using methods
For more info
you can also use this snippet from https://www.journaldev.com/861/java-copy-file
private static void copyFileUsingStream(File source, File dest) throws IOException {
InputStream is = null;
OutputStream os = null;
try {
is = new FileInputStream(source);
os = new FileOutputStream(dest);
byte[] buffer = new byte[1024];
int length;
while ((length = is.read(buffer)) > 0) {
os.write(buffer, 0, length);
}
} finally {
is.close();
os.close();
}
}

#Pierre his code is perfect, however this is what I use so I won't be able to change the extension:
public static void copyWithDifferentName(File sourceFile, String newFileName) {
if (sourceFile == null || newFileName == null || newFileName.isEmpty()) {
return;
}
String extension = "";
if (sourceFile.getName().split("\\.").length > 1) {
extension = sourceFile.getName().split("\\.")[sourceFile.getName().split("\\.").length - 1];
}
String path = sourceFile.getAbsolutePath();
String newPath = path.substring(0, path.length() - sourceFile.getName().length()) + newFileName;
if (!extension.isEmpty()) {
newPath += "." + extension;
}
try (OutputStream out = new FileOutputStream(newPath)) {
Files.copy(sourceFile.toPath(), out);
} catch (IOException e) {
e.printStackTrace();
}
}

Creating a zip file containing Text Files

I've been trying to tackle this problem for a day or two and can't seem to figure out precisely how to add text files to a zip file, I was able to figure out how to add these text files to a 7zip file which was insanely easy, but a zip file seems to me much more complicated for some reason. I want to return a zip file for user reasons btw.
Here's what I have now:
(I know the code isn't too clean at the moment, I plan to tackle that after getting the bare functionality down).
private ZipOutputStream addThreadDumpsToZipFile(File file, List<Datapoint<ThreadDump>> allThreadDumps, List<Datapoint<String>> allThreadDumpTextFiles) {
ZipOutputStream threadDumpsZipFile = null;
try {
//creat new zip file which accepts input stream
//TODO missing step: create text files containing each thread dump then add to zip
threadDumpsZipFile = new ZipFile(new FileOutputStream(file));
FileInputStream fileInputStream = null;
try {
//add data to each thread dump entry
for(int i=0; i<allThreadDumpTextFiles.size();i++) {
//create file for each thread dump
File threadDumpFile = new File("thread_dump_"+i+".txt");
FileUtils.writeStringToFile(threadDumpFile,allThreadDumpTextFiles.get(i).toString());
//add entry/file to zip file (creates block to add input to)
ZipEntry threadDumpEntry = new ZipEntry("thread_dump_"+i); //might need to add extension here?
threadDumpsZipFile.putNextEntry(threadDumpEntry);
//add the content to this entry
fileInputStream = new FileInputStream(threadDumpFile);
byte[] byteBuffer = new byte[(int) threadDumpFile.length()]; //see if this sufficiently returns length of data
int bytesRead = -1;
while ((bytesRead = fileInputStream.read(byteBuffer)) != -1) {
threadDumpsZipFile.write(byteBuffer, 0, bytesRead);
}
}
threadDumpsZipFile.flush();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
fileInputStream.close();
} catch(Exception e) {
}
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return threadDumpsZipFile;
}
As you can sort of guess, I have a set of Thread Dumps that I want to add to my zip file and return to the user.
Let me know if you guys need any more info!
PS: There might be some bugs in this question, I just realized with some breakpoints that the threadDumpFile.length() won't really work.
Look forward to your replies!
Thanks,
Arsa

Here's a crack at it. I think you'll want to keep the file extensions when you make your ZipEntry objects. See if you can implement the below createTextFiles() function; the rest of this works -- I stubbed that method to return a single "test.txt" file with some dummy data to verify.
void zip()
{
try {
FileOutputStream fos = new FileOutputStream("yourZipFile.zip");
ZipOutputStream zos = new ZipOutputStream(fos);
File[] textFiles = createTextFiles(); // should be an easy step
for (int i = 0; i < files.length; i++) {
addToZipFile(file[i].getName(), zos);
}
zos.close();
fos.close();
} catch (Exception e) {
e.printStackTrace();
}
}
void addToZipFile(String fileName, ZipOutputStream zos) throws Exception {
File file = new File(fileName);
FileInputStream fis = new FileInputStream(file);
ZipEntry zipEntry = new ZipEntry(fileName);
zos.putNextEntry(zipEntry);
byte[] bytes = new byte[1024];
int length;
while ((length = fis.read(bytes)) >= 0) {
zos.write(bytes, 0, length);
}
zos.closeEntry();
fis.close();
}

Incorrect path to file

I don't know why but outStream = new FileOutputStream(file) and inStream = new FileInputStream(new File(file1.getName())) throw an exception. I have no idea what to do.
Here's some code of this:
File tempf = new File(cmds[1]); //cmds is a String with filename cmds[1] and pathname cmds[2] where to move the file
File tempw = new File(cmds[2]);
if(!tempf.isAbsolute() || !tempw.isAbsolute()){//here i make paths absolute
tempf = new File(tempf.getAbsolutePath());
tempw = new File(tempw.getAbsolutePath());
}
String from = cmds[1];
String where = cmds[2];
File file1 = tempf;
File file2 = new File (tempw.toString() + "/" + new File(cmds[1]).getName());
InputStream inStream = null;
OutputStream outStream = null;
try {
inStream = new FileInputStream(new File(file1.getName())); //throws an exception
outStream = new FileOutputStream(file2); //throws an exception too
byte[] buffer = new byte[16384];
int length;
while ((length = inStream.read(buffer)) > 0) {
outStream.write(buffer, 0, length);
}
if (inStream != null)
inStream.close();
if (outStream != null)
outStream.close();
file1.delete();
} catch (IOException e) {
System.err.println("permission denied");
}
} else {
System.err.println("incorrect syntax");
}
continue;
}
Looks like everything should work fine but it doesn't. I am getting
java.io.FileNotFoundException: C:\Users\Maxim\IdeaProjects\Testing\OneDrive\1234.txt
But as I see it's wrong path. Real path is C:\Users\Maxim\OneDrive
UPD! It's found out that the problem is that getAbsolutePath() returns a path where the project is, but it's not the path I need. I need C:\Users\Maxim\OneDrive BUT it returns C:\Users\Maxim\IdeaProjects\Testing\OneDrive BUT! .../Testng doesn't have OneDrive!

The constructors for FileInputStream and FileOutputStream throw errors if there is a problem accessing the file, like if it doesn't exist. To stop it from throwing a FileNotFoundException, make sure you create the file before instantiating a FileInput/OutputStream object.
try{
FileInputStream fis = new FileInputStream(file);
}catch(FileNotFoundException e){
e.printStackTrace();
}
Look at the documentation here.

Decompressing tar file with Apache Commons Compress

I'm using Apache Commons Compress to create tar archives and decompress them. My problems start with this method:
private void decompressFile(File file) throws IOException {
logger.info("Decompressing " + file.getName());
BufferedOutputStream outputStream = null;
TarArchiveInputStream tarInputStream = null;
try {
tarInputStream = new TarArchiveInputStream(
new FileInputStream(file));
TarArchiveEntry entry;
while ((entry = tarInputStream.getNextTarEntry()) != null) {
if (!entry.isDirectory()) {
File compressedFile = entry.getFile();
File tempFile = File.createTempFile(
compressedFile.getName(), "");
byte[] buffer = new byte[BUFFER_MAX_SIZE];
outputStream = new BufferedOutputStream(
new FileOutputStream(tempFile), BUFFER_MAX_SIZE);
int count = 0;
while ((count = tarInputStream.read(buffer, 0, BUFFER_MAX_SIZE)) != -1) {
outputStream.write(buffer, 0, count);
}
}
deleteFile(file);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (outputStream != null) {
outputStream.flush();
outputStream.close();
}
}
}
Every time I run the code, compressedFile variable is null, but the while loop is iterating over all entries in my test tar.
Could you help me to understand what I'm doing wrong?

From the official documentation
Reading entries from an tar archive:
TarArchiveEntry entry = tarInput.getNextTarEntry();
byte[] content = new byte[entry.getSize()];
LOOP UNTIL entry.getSize() HAS BEEN READ {
tarInput.read(content, offset, content.length - offset);
}
I have written an example starting from your implementation and testing with a very trivial .tar (just one entry of text).
Not knowing the exact requirement I just take care of solving the problem of reading the archive avoiding the nullpointer. Debugging, the entry is available as you also have found
private static void decompressFile(File file) throws IOException {
BufferedOutputStream outputStream = null;
TarArchiveInputStream tarInputStream = null;
try {
tarInputStream = new TarArchiveInputStream(
new FileInputStream(file));
TarArchiveEntry entry;
while ((entry = tarInputStream.getNextTarEntry()) != null) {
if (!entry.isDirectory()) {
File compressedFile = entry.getFile();
String name = entry.getName();
int size = 0;
int c;
while (size < entry.getSize()) {
c = tarInputStream.read();
System.out.print((char) c);
size++;
}
(.......)
AS I said: I tested with a tar including only an entry of text (you can also try this approach to verify the code) to be sure that the null is avoided.
You need to make all the needed adaptations for your real needs.
It is clear that you will have to handle streams as in the metacode I posted on top.
It shows how to deal with the single entries.

Try using getNextEntry() method instead of getNextTarEntry() method.
The second method returns a TarArchiveEntry. Probably this is not what you want!

Overwriting ZipEntrys

Simple question,
I'm writing a series of text files into a zip, just wrapping a fileoutputstream in a zipoutputstream and then in a printwriter.
public static int saveData(File outfile, DataStructure input) {
//variables
ArrayList<String> out = null;
FileOutputStream fileout = null;
ZipOutputStream zipout = null;
PrintWriter printer = null;
//parameter tests
try {
fileout = new FileOutputStream(outfile);
zipout = new ZipOutputStream(fileout);
printer = new PrintWriter(zipout);
} catch (Exception e) {
e.printStackTrace();
return util.FILE_INVALID;
}
for(DataItem data : input){
//process the data into a list of strings
try {
zipout.putNextEntry(new ZipEntry( dataFileName ));
for(String s : out) {
printer.println(s);
}
zipout.closeEntry();
} catch (Exception e) {
try {
fileout.close();
} catch (Exception x) {
x.printStackTrace();
return util.CRITICAL_ERROR;
}
e.printStackTrace();
return util.CRITICAL_ERROR;
}
}
try {
fileout.close();
} catch (Exception e) {
e.printStackTrace();
return util.CRITICAL_ERROR;
}
return util.SUCCESS;
}
Previously in the app i've been developing I've just been saving to the current directory for testing and I know in the case of a file already existing that the file will be overwritten (and have been exploiting this). What I dont know is the behaviour for zips. Will it overwrite entries of the same name? Or will it simply overwrite the whole zip file (which would be convenient for my purposes.
K.Barad

As Joel said, If you try to add a duplicate ZipEntry you will get an exception. If you want to replace the current entry you need to delete it and re-insert it.
You might want to do something like here below to achieve it:
private ZipFile addFileToExistingZip(File zipFile, File versionFile) throws IOException{
// get a temp file
File tempFile = File.createTempFile(zipFile.getName(), null);
// delete it, otherwise you cannot rename your existing zip to it.
tempFile.delete();
boolean renameOk=zipFile.renameTo(tempFile);
if (!renameOk)
{
throw new RuntimeException("could not rename the file "+zipFile.getAbsolutePath()+" to "+tempFile.getAbsolutePath());
}
byte[] buf = new byte[4096 * 1024];
ZipInputStream zin = new ZipInputStream(new FileInputStream(tempFile));
ZipOutputStream out = new ZipOutputStream(new FileOutputStream(zipFile));
ZipEntry entry = zin.getNextEntry();
while (entry != null) {
String name = entry.getName();
boolean toBeDeleted = false;
if (versionFile.getName().indexOf(name) != -1) {
toBeDeleted = true;
}
if(!toBeDeleted){
// Add ZIP entry to output stream.
out.putNextEntry(new ZipEntry(name));
// Transfer bytes from the ZIP file to the output file
int len;
while ((len = zin.read(buf)) > 0) {
out.write(buf, 0, len);
}
}
entry = zin.getNextEntry();
}
// Close the streams
zin.close();
// Compress the files
InputStream in = new FileInputStream(versionFile);
String fName = versionFile.getName();
// Add ZIP entry to output stream.
out.putNextEntry(new ZipEntry(fName));
// Transfer bytes from the file to the ZIP file
int len;
while ((len = in.read(buf)) > 0) {
out.write(buf, 0, len);
}
// Complete the entry
out.closeEntry();
in.close();
// Complete the ZIP file
out.close();
tempFile.delete();
return new ZipFile(zipFile);
}
The above code worked for me where the need was to add a new zip entry to an existing zip file. If the entry is already present inside the zip, then overwrite it.
Comments/improvements in the code are welcome!
Thanks!

If you try to add a duplicate ZipEntry you will get an exception. If you want to replace the current entry you need to delete it and re-insert it. I suspect the exception you get is much the same as this one.