I'm looking for an elegant way to remove all files in a folder that have the extension .jpg
I have the following to count the total jpg files in a folder:
Option(new File(path).list).map(_.filter(_.endsWith(".jpg")).size).getOrElse(0)
Thanks in advance, any help much appreciated :)
for {
files <- Option(new File(path).listFiles)
file <- files if file.getName.endsWith(".jpg")
} file.delete()
Some extra comment,
To extend #Debilski's answer:
Touching files obviously causes side effects. To make this functionally effectfull, please do something like:
def deleteFilesBySuffix[G[_]: Sync](suffix: String)(dirName: String): G[Unit] =
Sync[G].suspend(Sync[G].fromTry(Try(for {
files <- Option(new File(dirName).listFiles)
file <- files if file.getName.endsWith(suffix)
} file.delete())))
Then,
You'll have to run this code with an effect which can delay the
execution of this method like:
import cats.IO
import cats.syntax.foldable._
val r = deleteFilesBySuffix[IO]("jpg")("/tmp")
//Still nothing happened
//Another example with multiple dirs:
val dirNames = List("/tmp", "/tmp/myDir")
val res = dirNames.traverse_(deleteFilesBySuffix[IO]("jpg"))
//Actually run it..
r.unsafeRunSunc()
//Now files are deleted..
In my opinion this is much safer, and uses Scala's power of effects
os-lib lets you delete all files with a certain extension with a one liner:
os.list(os.pwd/"pics").filter(_.ext == "jpg").map(os.remove)
As described here, os-lib is the easiest way to perform filesystem operations with Scala. It lets you write beautiful, concise, Scala code without dealing with ugliness of the underlying Java libs.
Here's some setup code if you'd like to test this out on your machine:
os.makeDir(os.pwd/"pics")
os.write(os.pwd/"pics"/"family.jpg", "")
os.write(os.pwd/"pics"/"cousins.txt", "")
os.write(os.pwd/"pics"/"gf.jpg", "")
os.write(os.pwd/"pics"/"friend.gif", "")
Related
I need to read a text file with readLines() and I've already found this question, but the code in the answers always uses some variation of javaClass; it seems to work only inside a class, while I'm using just a simple Kotlin file with no declared classes. Writing it like this is correct syntax-wise but it looks really ugly and it always returns null, so it must be wrong:
val lines = object {}.javaClass.getResource("file.txt")?.toURI()?.toPath()?.readLines()
Of course I could just specify the raw path like this, but I wonder if there's a better way:
val lines = File("src/main/resources/file.txt").readLines()
Thanks to this answer for providing the correct way to read the file. Currently, reading files from resources without using javaClass or similar constructs doesn't seem to be possible.
// use this if you're inside a class
val lines = this::class.java.getResourceAsStream("file.txt")?.bufferedReader()?.readLines()
// use this otherwise
val lines = object {}.javaClass.getResourceAsStream("file.txt")?.bufferedReader()?.readLines()
According to other similar questions I've found, the second way might also work within a lambda but I haven't tested it. Notice the need for the ?. operator and the lines?.let {} syntax needed from this point onward, because getResourceAsStream() returns null if no resource is found with the given name.
Kotlin doesn't have its own means of getting a resource, so you have to use Java's method Class.getResource. You should not assume that the resource is a file (i.e. don't use toPath) as it could well be an entry in a jar, and not a file on the file system. To read a resource, it is easier to get the resource as an InputStream and then read lines from it:
val lines = this::class.java.getResourceAsStream("file.txt").bufferedReader().readLines()
I'm not sure if my response attempts to answer your exact question, but perhaps you could do something like this:
I'm guessing in the final use case, the file names would be dynamic - Not statically declared. In which case, if you have access to or know the path to the folder, you could do something like this:
// Create an extension function on the String class to retrieve a list of
// files available within a folder. Though I have not added a check here
// to validate this, a condition can be added to assert if the extension
// called is executed on a folder or not
fun String.getFilesInFolder(): Array<out File>? = with(File(this)) { return listFiles() }
// Call the extension function on the String folder path wherever required
fun retrieveFiles(): Array<out File>? = [PATH TO FOLDER].getFilesInFolder()
Once you have a reference to the List<out File> object, you could do something like this:
// Create an extension function to read
fun File.retrieveContent() = readLines()
// You can can further expand this use case to conditionally return
// readLines() or entire file data using a buffered reader or convert file
// content to a Data class through GSON/whatever.
// You can use Generic Constraints
// Refer this article for possibilities
// https://kotlinlang.org/docs/generics.html#generic-constraints
// Then simply call this extension function after retrieving files in the folder.
listOfFiles?.forEach { singleFile -> println(singleFile.retrieveContent()) }
In order to have the same url that work for both Jar or in local, the url (or path) needs to be a relative path from the repository root.
..meaning, the location of your file or folder from your src folder.
could be "/main/resources/your-folder/" or "/client/notes/somefile.md"
The url must be a relative path from the repository root.
it must be "src/main/resources/your-folder/" or "src/client/notes/somefile.md"
Now you get the drill, and luckily for Intellij Idea users, you can get the correct path with a right-click on the folder or file -> copy Path/Reference.. -> Path From Repository Root (this is it)
Last, paste it and do your thing.
I am new to jmeter & I am looking for an option to compare two files using Jmeter. Both the files are generated using Save Response to file in jmeter. Also both files contain response to a jdbc request, with 100s of values across multiple columns & rows. I am using __FileToString() function in my response assertion to compare the two files. But this fails if my file has data with some special chars. Any tips how could I handle this ? OR any other ways to compare two Jmeter created files ? I would also want to know the records that are different in both files.
I know files could be compared using a lot of other tools, but I would really want to do this using Jmeter please. Thank you!
You can do it using JSR223 Sampler and Groovy language. For example this code allows comparison of two text files:
def file1 = new File('/path/to/file1')
def file2 = new File('/path/to/file2')
def file1Lines = file1.readLines('UTF-8')
def file2Lines = file2.readLines('UTF-8')
if (file1Lines.size() != file2Lines.size()) {
SampleResult.setSuccessful(false)
SampleResult.setResponseMessage('Files size is different, omitting line-by-line compare')
} else {
def differences = new StringBuilder()
file1Lines.eachWithIndex { String file1Line, int number ->
String file2Line = file2Lines.get(number)
if (!file1Line.equals(file2Line)) {
differences.append('Difference # ').append(number).append('. Expected: ')
.append(file1Line).append('. Actual: ' + file2Line)
differences.append(System.getProperty('line.separator'))
}
}
if (differences.toString().length() > 0) {
SampleResult.setSuccessful(false)
SampleResult.setResponseMessage(differences.toString())
}
}
In case of any differences, the sampler will fail and you will see the information about deltas in the "Response Message" section:
Not that this will not necessary work for all types of files, for example, binary files.
References:
Groovy: reading files
SampleResult class JavaDoc
Apache Groovy - Why and How You Should Use It
Trying to put together a file diff route... could someone help? here is what I have ->
CsvDataFormat csv = new CsvDataFormat();
csv.setDelimiter(",");
from("file:inputdir?delete=true&sortBy=ignoreCase:file:name")
.unmarshal(csv)
.pollEnrich("file:backup?fileName=test.csv&sendEmptyMessageWhenIdle=true")
.unmarshal(csv)
// Need to aggregate here!!!!
.log("test");
A csv file gets dropped in the /input directory and then a backup file is consumed from the /backup directory. I would like to compare these two files and output the difference.
This is not a specific Camel problem. In order to solve this problem you may implement a diff functionality on your own, or you may use an existing library such as java-diff-utils.
Pseudocode:
// read file 1 into a list "list1"
// read file 2 into a list "list2"
// use java-diff-utils to calculate the difference
Patch patch = DiffUtils.diff(list1, list2);
Does Octave have a good way to let the user select an input file? I've seen code like this for Matlab, but doesn't work in Octave.
A gui based method would be preferred, but some sort of command-line choice would work also. It would be great if there were some way to do this that would work in both Matlab and Octave.
I found this for Matlab but it does not work in Octave, even when you install Octave Forge Java package for the listdlg function. In Octave, dir() gives you:
647x1 struct array containing the fields:
name
date
bytes
isdir
datenum
statinfo
but I don't know how to convert this to an array of strings listdlg expects.
You have already the Octave Forge java package installed, so you can create instances of any java class and call any java method.
For example to create a JFileChooser and call the JFileChooser.showOpenDialog(Component parent) method:
frame = javaObject("javax.swing.JFrame");
frame.setBounds(0,0,100,100);
frame.setVisible(true);
fc = javaObject ("javax.swing.JFileChooser")
returnVal = fc.showOpenDialog(frame);
file = fc.getSelectedFile();
file.getName()
Btw. I had some troubles installing the package.
Here is a fix for Ubuntu. that worked also for my Debian Testing.
EDIT
#NoBugs In reply to your comment:
If you need to use listdlg you can do the following:
d = dir;
str = {d.name};
[sel,ok] = listdlg('PromptString','Select a file:',...
'SelectionMode','single',...
'ListString',str);
if ok == 1
disp(str{sel(1)});
end
This should be compatible with matlab, by I cannot test it right now.
If you want to select multiple files use this:
d = dir;
str = {d.name};
[sel,ok] = listdlg('PromptString','Select a file:',...
'SelectionMode','multiple',...
'ListString',str);
if ok == 1
imax = length(sel);
for i=1:1:imax
disp(str{sel(i)});
end
end
I never came across an open-file-dialog in octave.
If you are looking for a gui based method maybe guioctave can help you. I never used it, because it appears only be available for windows machines.
A possible solution would be to write a little script in octave, that would allow the user to parse through the directories and select a file like that.
Thought I'd provide an updated answer to this old question, since it is appearing in the 'related questions' field for other questions.
Octave provides the uigetdir and uigetfile functions, which do what you expect.
I would like to get all the files that a sub-folder holds in a string array.
So, I have tried something like the following:
var IOstore = IsolatedStorageFile.GetUserStoreForApplication();
string searchpath = System.IO.Path.Combine("product", ProductName);
string filesInSubDirs[] = IOstore.GetFileNames(searchpath);
But I got all the files in the "product" folder. I have also tried with "productname" only as the parameter.
Thanks for your help.
The search pattern for a sub-folder needs to include "*.*" at the end to pattern match any file, which would make your code something like the following:
var IOstore = IsolatedStorageFile.GetUserStoreForApplication();
string searchpath = System.IO.Path.Combine("product", ProductName);
searchpath = string.Format("{0}\\*.*", searchpath);
string filesInSubDirs[] = IOstore.GetFileNames(searchpath);
Something you might want to try. (this is sort of a left field answer, sorry). In my dropbox client http://sharpdropbox.codeplex.com/) I have a set of facades for System.IO.File, System.IO.FileInfo, System.IO.Directory, and System.IO.DirectoryInfo. They work pretty good and I have tested them.
Basically, you add a Using or Import for System.IO.IsolatedStorage and then PSFile, PSDirectory, PSFileInfo, or PSDirectoryInfo. It's saved me from having to remember all the nuances... for instance if you are querying a directory, it knows to add a slash, etc. BTW, the "PS" prefix stands for "Persisted Storage" which is what IsolatedStorage is sometimes called (starting them with an "I" implies they are interfaces.. and having no prefix makes things even more confusing).
Anyway, you can grab the code from source or I believe the last release had the DLLs for them (it's called something like "IsolatedStorageFacade-WP7")