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How to differentiate between an empty file that has no extension and a directory in java?

Let's suppose I have a zip file containing two elements: elem1 (created by linux command touch elem1) and elem2 (created by linux command mkdir elem2)
Now, in java, I use the following code to extract the content of the zip
// ...
// Suppose we have a valid inputStream on a zip file
// ...
ZipInputStream zipInputStream = new ZipInputStream(inputStream);
ZipEntry entry = zipInputStream.getNextEntry();
while (entry != null) {
int entrySize = (int) entry.getSize();
File file = Paths.get(extractPath).resolve(entry.getName()).toFile();
if (/*Condition to detect a directory*/) {
System.out.println("This is a directory");
FileUtils.forceMkdir(file);
} else if (/*Condition to detect an empty file*/) {
System.out.println("This is an empty file");
} else {
System.out.println("This is something else");
}
entry = zipInputStream.getNextEntry();
}
I would like to specify the right conditions to detect whether entry is a directory, or an empty file without extension. Knowing that these entries are still in memory and do not exist on the filesystem, the command file.isDirectory() always returns false; so I cannot not use it to check for directory.
Any ideas please ?

I created both an empty folder and an empty file without extension and evaluated them with the code below:
public static void main(String[] args) {
String path = System.getProperty("user.home") + File.separator + "Desktop" + File.separator;
File file = new File(path + "EmptyFile");
File folder = new File (path + "EmptyFolder");
System.out.println("Is 'folder' a folder? " + (Files.isDirectory(folder.toPath())? "Yes" : "No" ));
System.out.println("Is 'file' a folder? " + (Files.isDirectory(file.toPath())? "Yes" : "No" ));
}
The (not surprising) result:
Is 'folder' a folder? Yes
Is 'file' a folder? No
The reason why this works is because the function Files.isDirectory(...) looks in the file attributes set by the Operating System to determine whether the item being examined is a "File folder" or simply a "file". My assumption is that Zip programs do not contain such metadata (not even Windows zip). Therefore, "isDirectory" test cannot be performed using the Files.isDirectory(...) function. My quick research discovered that, the way to do this (and I am kind of shocked) is by examining the file name and check to see if the name ends with the file separator. In fact, this is how ZipEntry.isDirectory() works.
Attempting to zip an empty folder is not allowed for Windows zip (maybe allowed with other software?). However, I was able to include empty directories with 7-zip. That wasn't the only difference. The isDirectory() test failed when the zip was created with Windows zip because the file was skipped altogether. So, in order for this to work, create the zip file with zip software other than the one that comes with Windows. Then,
public static void main(String[] args) throws IOException {
String path = System.getProperty("user.home") + File.separator + "Desktop" + File.separator;
FileInputStream inputStream = new FileInputStream(path + "Desktop.zip");
ZipInputStream zipInputStream = new ZipInputStream(inputStream);
ZipEntry entry = zipInputStream.getNextEntry();
while (entry != null) {
File file = Paths.get(entry.getName()).toFile();
if (entry.isDirectory()) {
System.out.println(entry.getName() + " is a directory");
} else if (file.getName().endsWith(".lnk")) {
System.out.println(file.getName() + " is a shortcut");
} else {
System.out.println(entry.getName() + " is a file");
}
entry = zipInputStream.getNextEntry();
}
zipInputStream.close();
}
Outputs for me:
EmptyFile is a file
EmptyFolder/ is a directory
How We Test Wireless Routers _ PCMag_files/ is a directory
How We Test Wireless Routers _ PCMag_files/00hSyhn9j5PNrcOot1tMzz9.1578945749.fit_lim.size_100x100.png is a file
...
etc
One last note... obviously, if a ZipEntry is not a directory, it is a file. Therefore, no else if is needed. That is, unless you would like to make a distinction between file types. In the example above, I wanted to check if a particular file was a shortcut. Just keep in mind that this is not necessary. The logic should only test entries for isDirectory and if the test fails, it is simply a file.

Directory not showing up in desktop, and file not being created?

The following program has the purpose of creating a directory,
folderforallofmyjavafiles.mkdir();
and making a file to go inside that directory,
File myfile = new File("C:\\Users\\username\\Desktop\\folderforallofmyjavafiles\\test.txt");
There are two problems though. One is that it says the directory is being created at the desktop, but when checking for the directory, it is not there. Also, when creating the file, I get the exception
ERROR: java.io.FileNotFoundException: folderforallofmyjavafiles\test.txt (The system cannot find the path specified)
Please help me resolve these issues, here is the full code:
package mypackage;
import java.io.*;
public class Createwriteaddopenread {
public static void main(String[] args) {
File folderforallofmyjavafiles = new File("C:\\Users\\username\\Desktop");
try {
folderforallofmyjavafiles.mkdir(); //Creates a directory (mkdirs makes a directory)
if (folderforallofmyjavafiles.isDirectory() == true) {
System.out.println("Folder created at " + "'" + folderforallofmyjavafiles.getPath() + "'");
}
} catch (Exception e) {
System.out.println("Not working...?");
}
File myfile = new File("C:\\Users\\username\\Desktop\\folderforallofmyjavafiles\\test.txt");
//I even tried this:
//File myfile = new File("folderforallofmyjavafiles/test.txt");
//write your name and age through the file
try {
PrintWriter output = new PrintWriter(myfile); //Going to write to myfile
//This may throw an exception, so I always need a try catch when writing to a file
output.println("myname");
output.println("myage");
output.close();
System.out.println("File created");
} catch (IOException e) {
System.out.printf("ERROR: %s\n", e); //e is the IOException
}
}
}
Thank you so much for helping me out, I really appreciate it.
:)

You're creating the Desktop folder in the C:\Users\username folder. If you check the return value of mkdir, you'd notice it's false because the folder already exists.
How would the system know that you want a folder named folderforallofmyjavafiles unless you tell it so?
So, you didn't create the folder, and then you try to create a file in the (nonexistent) folder, and Java tells you the folder doesn't exist.
Agreed that it's a bit obscure, using a FileNotFoundException, but the text does say "The system cannot find the path specified".
Update
You're probably confused about the variable name, so let me say this. The following are all the same:
File folderforallofmyjavafiles = new File("C:\\Users\\username\\Desktop");
folderforallofmyjavafiles.mkdir();
File x = new File("C:\\Users\\username\\Desktop");
x.mkdir();
File folderToCreate = new File("C:\\Users\\username\\Desktop");
folderToCreate.mkdir();
File gobbledygook = new File("C:\\Users\\username\\Desktop");
gobbledygook.mkdir();
new File("C:\\Users\\username\\Desktop").mkdir();

Error in file is :- java.io.FileNotFoundException: \files\storetime.txt (The system cannot find the path specified)

i am using eclipse for develop the java desktop application and working with file but got the above error
my code is as following please try to help me how to give path in eclipse and also get same problem to load image from the given task
i have put the "files" folder out side the "src" folder
how to give path dynamically
my code is ass following
public int getTimeId()
{
LOG.info("The File name is :- " + fileName);
LOG.info("The path is :- ");
int count=0;
FileInputStream fileInputStream;
ObjectInputStream objectInputStream;
try
{
fileInputStream=new FileInputStream("/files/storetime.txt");
objectInputStream=new ObjectInputStream(fileInputStream);
while(objectInputStream.readObject()!=null)
{
count++;
}
}
catch(IOException e)
{
System.out.println("Error in file is :- " + e);
} catch (ClassNotFoundException e) {
System.out.println("Error in class not found :- " + e);
}
return count;
}
}

You are providing the absolute path by prep-ending / in the path. It means root directory in Unix file system. so, you have to give a relative path of the file from the current directory.You can put files directory in the root directory of your project folder and use
fileInputStream=new FileInputStream("files/storetime.txt");
So, it will be picked up

Use FileInputStream(new File("files/storetime.txt")); don't use /file -> it will check for /file partition in linux as /root

Java I/O issue when dealing with files

I'm currently learning Java I/O , when I compile this code :
import java.io.File;
public class Main {public static void main(String[] args){
//Creation of the File object
File f = new File("test.txt");
System.out.println("File absolute path : " + f.getAbsolutePath());
System.out.println("File name : " + f.getName());
System.out.println("Does it exist ? " + f.exists());
System.out.println("Is it a directory? " + f.isDirectory());
System.out.println("Is it a file ? " + f.isFile());
}
The problem is f.exists() and f.isFile()return false
How is that even possible ?

File f = new File("test.txt");
The above line doesn't create an physical file on the disk. it only creates a file object, with the name 'test.txt', thus File#exits() returns false.
You need to create an actual physical file in number of ways.
Using File
file.createNewFile()
using FileWriter
FileWriter writer = new FileWriter(f);
PS: same applies for File#isFile() returning false as well.

File is not a file—it is just a descriptor of a native filesystem resource that may or may not exist. For example, you can do new File(path).createNewFile().

new File("test.txt") It creates a new File instance by converting the given pathname string into an abstract pathname not physical file.
you can call File#createNewFile(). It atomically creates a new, empty file named by this abstract pathname if and only if a file with this name does not yet exist.

there is nothing wrong with the program except the file location
there are two solutions
1 : you can store the file in the project directory , parallel to src folder
2 you can create the file with full path specified
File f = new File("D:/folder1/folder2/applicationname/src/test.txt");

Can't delete file after being renamed (file is opened)

I am using icefaces to upload files to relative path in my web app (mywebapp/audio), then after the file is getting uploaded I rename it to save its extension as follows:
public static File changeExtToWav(FileInfo fileInfo,
StringBuffer originalFileName) {
log.debug("changeExtToWav");
int mid = fileInfo.getFile().getName().lastIndexOf(".");
String fileName = fileInfo.getFile().getName().substring(0, mid);
originalFileName.append(fileName);
log.debug("originalFileName: " + originalFileName);
String newFileName = fileName + "_" + new Date().getTime() + "."
+ "wav";
File newFile = new File(fileInfo.getFile().getParent() + "/"
+ newFileName);
log.debug("newFileName: " + newFile.getName());
fileInfo.getFile().renameTo(newFile);
return newFile;
}
after the file is getting uploaded, sometimes I want to delete it from UI button as follows:
try {
File fileToDelete = new File(filePath); // correct file path
log.debug("file exists: " + fileToDelete.exists()); // true
fileToDelete.delete();
} catch (Exception e) {
e.printStackTrace();
}
the file path is correct, and I get no exceptions, but the file is not deleted (I am using java 6 btw).
please advise how to fix this issue.
UPDATE: using the following useful method, I can get that the file is opened, any ideas how to close it ?
public String getReasonForFileDeletionFailureInPlainEnglish(File file) {
try {
if (!file.exists())
return "It doesn't exist in the first place.";
else if (file.isDirectory() && file.list().length > 0)
return "It's a directory and it's not empty.";
else
return "Somebody else has it open, we don't have write permissions, or somebody stole my disk.";
} catch (SecurityException e) {
return "We're sandboxed and don't have filesystem access.";
}
}

Well if the file is open, then there is two solutions :
You have a stream in your program open on this file. Note that afaik it's a problem on Windows, with Unix I can delete a File even if a stream is opened on it.
You have an other process using this file. So in this case you can't do anything from Java.
In the log it tells also that it can be a permission problem, are you sure you have enough privileges?
You can also use Files#delete(Path path) (jdk7) to have more details about the issue.