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Copy files from one directory to another and append new files with timestamp instead of overwriting in Java

I want to copy files from source directory to destination. If the file already exists in the destination directory, then append the new file to be copied with its timestamp so that there is no overwrite. How do I check for duplicates and append timestamp to the new file name? Please help!
public static void copyFolder(File src, File dest)
throws IOException{
//list all the directory contents
String files[] = src.list();
for (String file : files) {
//construct the src and dest file structure
File srcFile = new File(src, file);
File destFile = new File(dest, file);
//recursive copy
copyFolder(srcFile,destFile);
}
}else{
//if file, then copy it
//Use bytes stream to support all file types
InputStream in = new FileInputStream(src);
OutputStream out = new FileOutputStream(dest);
byte[] buffer = new byte[1024];
int length;
//copy the file content in bytes
while ((length = in.read(buffer)) > 0){
out.write(buffer, 0, length);
}
in.close();
out.close();
System.out.println("File copied from " + src + " to " + dest);
}
}

//construct the src and dest file structure
File srcFile = new File(src, file);
File destFile = new File(dest, file);
while (destFile.exists()) {
destFile = new File(dest, file + '-' + Instant.now());
}
In one case the destination file got named test-file.txt-2018-03-14T11:05:21.103706Z. The time given is in UTC. In any case you will end up with a name of file that doesn’t already exist (if the loop terminates, but I have a hard time seeing the scenario where it doesn’t).
You may want to append the timestamp only to plain files and reuse existing folders (directories), I don’t know your requirements here. And you may want to append the timestamp before the extension if there is one (to get test-file-2018-03-14T11:05:21.103706Z.txt instead). I trust you to make the necessary modifications.

You can check if the file exists using File.exist() method, if exists, you can open the file in the append mode
The code is something like this
File f = new File(oldName);
if(f.exists() && !f.isDirectory()) {
long currentTime=System.currentTimeMillis();
String newName=oldName+currentTime;
// do the copy
}

Delete and move file to a directory in java

I am trying to move a file from one directory to another using renameTo() in java, however renameTo doesnt work (doesnt rename and move the file). Basically, I want to delete the file in one first with same file name, then copy a file from anoter directory to the same location where I deleted the file originally, then copy the new one with same name.
//filePath = location of original file with file name appended. ex: C:\Dir\file.txt
//tempPath = Location of file that I want to replace it to file file without the file name. ex: C:\AnotherDir
int pos = filePath.indexOf("C:\\Dir\\file.txt");
//Parse out only the path, so just C:\\Dir
String newFilePath = filePath.substring(0,pos-1);
//I want to delete the original file
File deletefile = new File(newFilePath,"file.txt");
if (deletefile.exists()) {
success = deletefile.delete();
}
//There is file already exists in the directory, but I am just appending .tmp at the end
File newFile = new File(tempPath + "file.txt" + ".tmp");
//Create original file again with same name.
File oldFile = new File(newFilePath, "file.txt");
success = oldFile.renameTo(newFile); // This doesnt work.
Can you tell me what I am doing wrong?
Thanks for your help.

You need to escape the backslashes in the string literal: "C:\\Dir\\file.txt". Or use File.separator to construct the path.
Additionally, ensure newFile's path is constructed properly:
File newFile = new File(tempPath + File.separator + "file.txt" + ".tmp");
//^^^^^^^^^^^^^^^^
as the commments in the posted code (...ex: C:\AnotherDir) indicate that tempPath has no trailing slash character.

I have moved files to the destination directory and after moving deleted those moved files from source folder, in three ways, and at last am using the 3rd approach in my project.
1st approach:
File folder = new File("SourceDirectory_Path");
File[] listOfFiles = folder.listFiles();
for (int i = 0; i < listOfFiles.length; i++) {
Files.move(Paths.get("SourceDirectory_Path"+listOfFiles[i].getName()), Paths.get("DestinationDerectory_Path"+listOfFiles[i].getName()));
}
System.out.println("SUCCESS");
2nd approach:
Path sourceDir = Paths.get("SourceDirectory_Path");
Path destinationDir = Paths.get("DestinationDerectory_Path");
try(DirectoryStream<Path> directoryStream = Files.newDirectoryStream(sourceDir)){
for (Path path : directoryStream) {
File d1 = sourceDir.resolve(path.getFileName()).toFile();
File d2 = destinationDir.resolve(path.getFileName()).toFile();
File oldFile = path.toFile();
if(oldFile.renameTo(d2)){
System.out.println("Moved");
}else{
System.out.println("Not Moved");
}
}
}catch (Exception e) {
e.printStackTrace();
}
3rd approach:
Path sourceDirectory= Paths.get(SOURCE_FILE_PATH);
Path destinationDirectory = Paths.get(SOURCE_FILE_MOVE_PATH);
try (DirectoryStream<Path> directoryStream = Files.newDirectoryStream(sourceDirectory)) {
for (Path path : directoryStream) {
Path dpath = destinationDirectory .resolve(path.getFileName());
Files.move(path, dpath, StandardCopyOption.REPLACE_EXISTING);
}
} catch (IOException ex) {
ex.printStackTrace();
}
Happy Coding !! :)

Error in Selecting multiple files into one zip and downloading the zip file?

<% // Set the content type based to zip
response.setContentType("Content-type:text/zip");
response.setHeader("Content-Disposition", "attachment; filename=mytest.zip");
// List of files to be downloaded
List files = new ArrayList();
files.add(new File("C:/first.txt"));
files.add(new File("C:/second.txt"));
files.add(new File("C:/third.txt"));
ServletOutputStream out1 = response.getOutputStream();
ZipOutputStream zos = new ZipOutputStream(new BufferedOutputStream(out1));
for (Object file : files)
{
//System.out.println("Adding file " + file.getName());
System.out.println("Adding file " + file.getClass().getName());
//zos.putNextEntry(new ZipEntry(file.getName()));
zos.putNextEntry(new ZipEntry(file.getClass().getName()));
// Get the file
FileInputStream fis = null;
try {
fis = new FileInputStream(file);
} catch (Exception E) {
// If the file does not exists, write an error entry instead of file contents
//zos.write(("ERROR: Could not find file " + file.getName()).getBytes());
zos.write(("ERROR: Could not find file" +file.getClass().getName()).getBytes());
zos.closeEntry();
//System.out.println("Could not find file "+ file.getAbsolutePath());
continue;
}
BufferedInputStream fif = new BufferedInputStream(fis);
// Write the contents of the file
int data = 0;
while ((data = fif.read()) != -1) {
zos.write(data);
}
fif.close();
zos.closeEntry();
//System.out.println("Finished adding file " + file.getName());
System.out.println("Finished adding file " + file.getClass().getName());
}
zos.close();
%>
this is my actualy program , want to zip multiple file and then downloading it , is wat i am doing the way is right or wrong , am new to JAVA programming , can you help me out ???

Your for loop should look like this:
for (File file : files) {
...
or
for (String file : files) {
...
The way you declared file variable, makes compiler assume it's an Object, and not a File instance. Thus, you get compilation error, because there is no FileInputStream constructor accepting an Object. The file must either be a File or a String containing absolute path to a file.
Another error is the way, you're passing file's name to the ZipEntry.
Using:
file.getClass().getName()
will result in "java.io.File" or "java.lang.String", and not the file name.
To set the proper name of the file, use File#getName().

java.util.zip has problems with periods in filenames / directorynames?

I want to unzip an iPhone app .ipa file.
This is actually zip file that extracts normally.
But the actual app file in it is a folder with the ending .app ( as all mac applications are actually folders with the ending .app).
Now the period seems to be a problem for java.util.zip.
public static void main(String[] args) throws IOException {
ZipFile zipFile = new ZipFile("file.zip");
String path = "";
Enumeration files = zipFile.entries();
while (files.hasMoreElements()) {
ZipEntry entry = (ZipEntry) files.nextElement();
if (entry.isDirectory()) {
File file = new File(path + entry.getName());
file.mkdir();
System.out.println("Create dir " + entry.getName());
} else {
File f = new File(entry.getName());
FileOutputStream fos = new FileOutputStream(f); //EXception occurs here
InputStream is = zipFile.getInputStream(entry);
byte[] buffer = new byte[1024];
int bytesRead = 0;
while ((bytesRead = is.read(buffer)) != -1) {
fos.write(buffer, 0, bytesRead);
}
fos.close();
System.out.println("Create File " + entry.getName());
}
}
}
This is my output:
Exception in thread "main" java.io.FileNotFoundException: Payload/SMA Jobs.app/06-magnifying-glass.png (No such file or directory)
at java.io.FileOutputStream.open(Native Method)
at java.io.FileOutputStream.<init>(FileOutputStream.java:179)
at java.io.FileOutputStream.<init>(FileOutputStream.java:131)
at Main.main(Main.java:27)
enter code here
Anyone knows how to handle those periods?

First of all, you should use mkdirs(), not mkdir().
second, zip files don't always include all the directory entries (or have them in the right order). the best practice is to make the directories in both branches of the code, so add:
} else {
File f = new File(entry.getName());
f.getParent().mkdirs();
(you should add some checking to make sure getParent() is not null, etc).

I don't think the period is the problem. Look at the absolute path of the file you are trying to output and make sure it is pointing to the correct place.

if (entry.isDirectory()) {
File file = new File(path + entry.getName());
....
} else {
File f = new File(entry.getName());
....
While creating directory, file path passed is path + entry.getName()
but while creating file, file path passed is entry.getName()
After changing file path to path + entry.getName(), code works for period file names and normal file names. :)

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.