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Provide log if the two files are identical and has same contents in Java

I have below code where i am reading the file from particular directory, processing it and once processed i am moving the file to archive directory. This is working fine. I am receiving new file everyday and i am using Control-M scheduler job to run this process.
Now in next run i am reading the new file from that particularly directory again and checking this file with the file in the archive directory and if the content is different then only process the file else dont do anything. There is shell script written to do this job and we dont see any log for this process.
Now i want to produce log message in my java code if the files are identical from the particular directory and in the archive directory then generate log that 'files are identical'. But i dont know exactly how to do this. I dont want to write the the logic to process or move anything in the file ..i just need to check the files are equal and if it is then
produce log message. The file which i recieve are not very big and the max size can be till 10MB.
Below is my code:
for(Path inputFile : pathsToProcess) {
// read in the file:
readFile(inputFile.toAbsolutePath().toString());
// move the file away into the archive:
Path archiveDir = Paths.get(applicationContext.getEnvironment().getProperty(".archive.dir"));
Files.move(inputFile, archiveDir.resolve(inputFile.getFileName()),StandardCopyOption.REPLACE_EXISTING);
}
return true;
}
private void readFile(String inputFile) throws IOException, FileNotFoundException {
log.info("Import " + inputFile);
try (InputStream is = new FileInputStream(inputFile);
Reader underlyingReader = inputFile.endsWith("gz")
? new InputStreamReader(new GZIPInputStream(is), DEFAULT_CHARSET)
: new InputStreamReader(is, DEFAULT_CHARSET);
BufferedReader reader = new BufferedReader(underlyingReader)) {
if (isPxFile(inputFile)) {
Importer.processField(reader, tablenameFromFilename(inputFile));
} else {
Importer.processFile(reader, tablenameFromFilename(inputFile));
}
}
log.info("Import Complete");
}
}

Based on the limited information about the size of file or performance needs, something like this can be done. This may not be 100% optimized, but just an example. You may also have to do some exception handling in the main method, since the new method might throw an IOException:
import org.apache.commons.io.FileUtils; // Add this import statement at the top
// Moved this statement outside the for loop, as it seems there is no need to fetch the archive directory path multiple times.
Path archiveDir = Paths.get(applicationContext.getEnvironment().getProperty("betl..archive.dir"));
for(Path inputFile : pathsToProcess) {
// Added this code
if(checkIfFileMatches(inputFile, archiveDir); {
// Add the logger here.
}
//Added the else condition, so that if the files do not match, only then you read, process in DB and move the file over to the archive.
else {
// read in the file:
readFile(inputFile.toAbsolutePath().toString());
Files.move(inputFile, archiveDir.resolve(inputFile.getFileName()),StandardCopyOption.REPLACE_EXISTING);
}
}
//Added this method to check if the source file and the target file contents are same.
// This will need an import of the FileUtils class. You may change the approach to use any other utility file, or read the data byte by byte and compare. If the files are very large, probably better to use Buffered file reader.
private boolean checkIfFileMatches(Path sourceFilePath, Path targetDirectoryPath) throws IOException {
if (sourceFilePath != null) { // may not need this check
File sourceFile = sourceFilePath.toFile();
String fileName = sourceFile.getName();
File targetFile = new File(targetDirectoryPath + "/" + fileName);
if (targetFile.exists()) {
return FileUtils.contentEquals(sourceFile, targetFile);
}
}
return false;
}

Wrong filepath in java

So we got this assignment in a basic java programming course and we're supposed to implement a kind of card deck. To help us with this they have given us resources that will present a GUI on the screen, but when running my program I get a IOException that says that it can't read the input file, most likely since the pathname is wrong. And I dont know how to fix it, we're not even supposed to be in meddling with this code. The error is thrown in this method:
private Image getImg(Card aCard) {
File pathToFile = null;
if (aCard == null) {
pathToFile = new File("cardset-oxymoron/shade.gif");
} else {
String suits = "cdhs";
char c = suits.charAt(aCard.getSuit());
String fileName = String.format("%s/%02d%c.gif", "cardset-oxymoron", aCard.getRank(), c);
pathToFile = new File(fileName);
}
Image img = null;
try {
img = ImageIO.read(pathToFile);
} catch (IOException ex) {
System.err.println("Failed to create image");
ex.printStackTrace();
}
return img;
}
And according to the error stack(?) it is at line 99, which is the
img = ImageIO.read(pathToFile);
line
The folder that the cards are in is inside the project folder, right in between bin and src. using IntelliJ debugger I can see that the the pathToFile is "cardset-oxymoron\02d.gif". The filename is correct as all the cards are "[01-13][c/d/h/s].gif". When I rightclicked and copied the path to the files inside IntelliJ it was using forwardsslashes and not backslashes. But then I checked in explorer and it was the other way around... I have no idea where this is going wrong, any input would be greatly appreciated!

According to your code your files are in directory cardset-oxymoron relative to your JVM run directory. I'm not sure about IntelliJ (I work all the time with Eclipse and Maven), but it could be bin directory.
You can check it by put those 2 lines to see what is it actually (somewhere before your actual code)
File currentDir = new File("./");
System.out.println(currentDir.getAbsolutePath());
Then your cardset-oxymoron must be in that directory. Or you can change file path appropriately.
E.g. if currentDir is bin then pathToFile will be
pathToFile = new File("../cardset-oxymoron/shade.gif");
as well as fileName for other case.

reading an external file using TextIO

I don't understand how to use TextIO's readFile(String Filename)
Can someone please explain how can I read an external file?
public static void readFile(String fileName) {
if (fileName == null) // Go back to reading standard input
readStandardInput();
else {
BufferedReader newin;
try {
newin = new BufferedReader( new FileReader(fileName) );
}
catch (Exception e) {
throw new IllegalArgumentException("Can't open file \"" + fileName + "\" for input.\n"
+ "(Error :" + e + ")");
}
if (! readingStandardInput) { // close current input stream
try {
in.close();
}
catch (Exception e) {
}
}
emptyBuffer(); // Added November 2007
in = newin;
readingStandardInput = false;
inputErrorCount = 0;
inputFileName = fileName;
}
}

I had to use TextIO for a school assignment and I got stuck on it too. The problem I had was that using the Scanner class I could just pass the name of the file as long as the file was in the same folder as my class.
Scanner fileScanner = new Scanner("data.txt");
That works fine. But with TextIO, this won't work;
TextIO.readfile("data.txt"); // can't find file
You have to include the path to the file like this;
TextIo.readfile("src/package/data.txt");
Not sure if there is a way to get it to work like the Scanner class or not, but this is what I've been doing in my course at school.

The above answer (about using the correct file name) is correct, however, as a clarification, make sure that you actually use the proper file path. The file path suggested above, i.e. src/package/ will not work in all circumstances. While this will be obvious to some, for those of you who need clarification, keep reading.
For example (and I use NetBeans), if you have already moved the file into NetBeans, and the file is already in the folder you want it to be in, then right click on the folder itself, and click 'properties'. Then expand the 'file path' section by clicking on the three dots next to the hidden file path. You will see the actual file path in its entirety.
For example, if the entire file path is:
C:\Users..\NetBeansProjects\IceCream\src\icecream\icecream.dat
Then, in the java code file itself, you can write:
TextIo.readfile("src/icecream/icecream.dat");
In other words, make sure you include the words 'src' but also everything that follows the src as well. If it's in the same folder as the rest of the files, you won't need anything prior to the 'src'.

How to search for files with a specific extention from a specifically given directory and all subdirectories

Just for my own learning, i am trying to find all mp3 files in my music collection and finding all the tracks which do not have id3v2 tags. My code gives me information about the directory i specify, but it doesn't look for the mp3 files in subdirectories. Although i can see that it recognises the directories as i can print them out. Please see my code below. I am very sorry if the formatting of the code is not correct. I am blind and using a screen reader and the formatter on this site is not very accessible to me.
public static int numberOfUntaggedTracks(String directory) throws UnsupportedTagException, InvalidDataException, IOException {
int untaggedTracks = 0;
File f = new File(directory);
File l[] = f.listFiles();
for (File x: l) {
if (x.isHidden() || !x.canRead())
continue;
if (x.isDirectory()) {
System.out.println("testing" + x.getPath());
numberOfUntaggedTracks(x.getPath());
} else if (x.getName().endsWith(".mp3")) {
Mp3File song = new Mp3File(x.getPath());
if (song.hasId3v1Tag() == false) {
untaggedTracks++;
}
//end of else if checking for .mp3 extension
}
//end of for loop
}
return untaggedTracks;
}

FileUtils from apatche commons-io has a listFiles method that should do what you need.
The method takes two IOFileFilter instances that you can use to filter files (mp3 files in your case) and to filter sub directories (so you can control which directories to include in your search).
To make your code work just change numberOfUntaggedTracks(x.getPath()); to untaggedTracks += numberOfUntaggedTracks(x.getPath());

Add file to a folder that is inside a zip file java

I am trying to add a txt file into a folder which is inside a zip file.
First, I was extracting all the contents of zip file then adding the txt file and then zipping back.
Then I read about the nio method which I can modify the zip without extracting it. Using this method I can add the txt file to the main folder of zip but I can't go deeper.
testing.zip file has res folder in it.
Here is my code:
Path txtFilePath = Paths.get("\\test\\prefs.txt");
Path zipFilePath = Paths.get("\\test\\testing.zip");
FileSystem fs;
try {
fs = FileSystems.newFileSystem(zipFilePath, null);
Path fileInsideZipPath = fs.getPath("res/prefs.txt"); //when I remover "res/" code works.
Files.copy(txtFilePath, fileInsideZipPath);
fs.close();
} catch (IOException e) {
e.printStackTrace();
}
I get the following exception:
java.nio.file.NoSuchFileException: res/

(edit to give the actual answer)
Do:
fs.getPath("res").resolve("prefs.txt")
instead of:
fs.getPath("res/prefs.txt")
The .resolve() method will do the correct thing with regards to file separators etc.

The fs.getPath("res/prefs.txt") should certainly work and you don't need to split it to fs.getPath("res").resolve("prefs.txt") as the approved answer says.
The exception java.nio.file.NoSuchFileException: res/ is slightly confusing because it mentions file but in fact directory is missing.
I had a similar problem and all I had to do was:
if (fileInsideZipPath.getParent() != null)
Files.createDirectories(fileInsideZipPath.getParent());
See full example:
#Test
public void testAddFileToArchive() throws Exception {
Path fileToAdd1 = rootTestFolder.resolve("notes1.txt");
addFileToArchive(archiveFile, "notes1.txt", fileToAdd1);
Path fileToAdd2 = rootTestFolder.resolve("notes2.txt");
addFileToArchive(archiveFile, "foo/bar/notes2.txt", fileToAdd2);
. . .
}
public void addFileToArchive(Path archiveFile, String pathInArchive, Path srcFile) throws Exception {
FileSystem fs = FileSystems.newFileSystem(archiveFile, null);
Path fileInsideZipPath = fs.getPath(pathInArchive);
if (fileInsideZipPath.getParent() != null) Files.createDirectories(fileInsideZipPath.getParent());
Files.copy(srcFile, fileInsideZipPath, StandardCopyOption.REPLACE_EXISTING);
fs.close();
}
If I remove Files.createDirectories() bit, and ensure clear start with clear test directory, I get:
java.nio.file.NoSuchFileException: foo/bar/
at com.sun.nio.zipfs.ZipFileSystem.checkParents(ZipFileSystem.java:863)
at com.sun.nio.zipfs.ZipFileSystem.newOutputStream(ZipFileSystem.java:528)
at com.sun.nio.zipfs.ZipPath.newOutputStream(ZipPath.java:792)
at com.sun.nio.zipfs.ZipFileSystemProvider.newOutputStream(ZipFileSystemProvider.java:285)
at java.nio.file.Files.newOutputStream(Files.java:216)
at java.nio.file.Files.copy(Files.java:3016)
at java.nio.file.CopyMoveHelper.copyToForeignTarget(CopyMoveHelper.java:126)
at java.nio.file.Files.copy(Files.java:1277)
at my.home.test.zipfs.TestBasicOperations.addFileToArchive(TestBasicOperations.java:111)
at my.home.test.zipfs.TestBasicOperations.testAddFileToArchive(TestBasicOperations.java:51)