Read Unknown File Names from Directory
I Would Like to Read a File from a Directory. in This Directory There Are Eight Additional Files with the Same Extension (. Csv). Likewise, the File Name Is...
I would like to read a file from a directory. In this directory there are eight additional files with the same extension (.csv). Likewise, the file name is not directly known. The name of the file looks like this:
test_file_1_2017_06_24.csv
It can change however, if I call the directory the next day . Then the file name is:
test_file_2_2017_06_25.csv or test_file_1_2017_06_25.
The name of the file and the date change. Is there a way to read the file "variable" in Java or to read the file but don´t know the exactly name? The directory is always the same ("H:/) (After the file read, then the file respectively the resulting string is furtherprocessed with split() ). Thanks for helpfull answers!
Edit: Read the directory and shows only csv-Files
File dir = new File("H:/");
File[] fileArray = dir.listFiles(new FilenameFilter() {
public boolean accept(File dir, String name) {
return name.endsWith(".csv");
}
});
for(File f: fileArray){
System.out.println(f.getName());
}
2 Answers
File directory = new File("H:/");
File[] allFilesInDir = directory.listFiles();
See ().
You can also provide a FilenameFilter to get only .csv files:
File[] allCsvFiles = directory.listFiles( new FilenameFilter() {
public boolean accept(File dir, String name) {
if ( name.toUpperCase().endsWith(".CSV") ) {
return new File(dir,name).isFile(); // Make sure we don't accept sub-directories ending in .csv
}
}
});
You can use the following code to go through a folder, check for csv files and work with it. Hope it helps.
File folder = new File("H:/"); /*path to your folder*/
String[] filesPresent = folder.list();
if(filesPresent.length==0){
System.out.println("Nothing to delete");
}else{
for(String fileName : filesPresent){ // looping through files in the directory
if(fileName.toLowerCase().endsWith(".csv") && (new File(fileName).isFile())){
//this is a csv file.
//you can do your operations here
File file = new File(fileName);
//now you can do any file operations required with the file object
}
}
}
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