java.lang.Object
- org.pipecraft.infra.io.FileUtils

```
public class FileUtils
extends Object
```
A set of utility methods for manipulating files

Author:

Eyal Schneider

Field Summary

Fields
Modifier and Type	Field	Description
`static String`	`CSV_EXTENSION`
`static String`	`CSV_GZ_EXTENSION`
`static String`	`CSV_ZSTD_EXTENSION`
`static String`	`GZ_EXTENSION`
`static String`	`NDJSON_EXTENSION`
`static Charset`	`UTF8`
`static String`	`ZSTD_EXTENSION`

Constructor Summary

Constructors
Constructor Description

FileUtils()

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static boolean`	`areIdentical(File file1, File file2)`	Compares two given files
`static void`	`close(Closeable closeable)`	Closes the closeable.
`static void`	`close(Closeable... closeables)`	Closes the resources in the order they are provided.
`static void`	`close(Collection<? extends Closeable> closeables)`	Closes the resources in the order they are provided.
`static void`	`closeSilently(Closeable... closeables)`	Closes the given closeables, in a silent manner (ignoring IOExceptions)
`static void`	`closeSilently(Collection<? extends Closeable> closeables)`	Closes the given closeables, in a silent manner (ignoring IOExceptions)
`static File`	`compress(File inFile, Compression compression)`	Compresses a given file, leaving the original.
`static File`	`compress(File inFile, Compression compression, int compressionLevel)`	Compresses a given file, leaving the original
`static void`	`compressAll(File folder, Compression compression, int parallelism)`	Compresses all files in the given folder, deleting the originals Original file names are appended the corresponding compression suffix (.gz/.zst).
`static void`	`compressAll(File folder, Compression compression, int compressionLevel, int parallelism)`	Compresses all files in the given folder, deleting the originals Original file names are appended the corresponding compression suffix (.gz/.zst).
`static void`	`copyFile(File src, File dst)`	Copies a file from one location to the other
`static void`	`copyFileToFolder(File src, File dstFolder)`	Copies a file from one location to the other, keeping the filename
`static File`	`createFolder(File parentFolder, String folderPath)`	creates a folder
`static File`	`createFolder(String folderPath)`	creates a folder, or keeps it if exists
`static File`	`createTempFile(String prefix, String suffix)`	Creates a unique temp file in the system's default tmp folder.
`static File`	`createTempFile(String prefix, String suffix, File folder)`	Creates a unique temp file in the given folder.
`static File`	`createTempFolder(String prefix)`	creates a temp folder under the system's default tmp folder
`static File`	`createTempFolder(String prefix, File parentFolder)`	creates a temp folder under a given parent folder
`static File`	`createUniqueFile(String prefix, String suffix)`	Creates a unique file in the system's default tmp folder.
`static File`	`createUniqueFile(String prefix, String suffix, File folder)`	Creates a unique file in the given folder.
`static File`	`createUniqueFolder(String prefix)`	creates a unique folder under the system's default tmp folder
`static File`	`createUniqueFolder(String prefix, File parentFolder)`	creates a unique folder under a given parent folder
`static File`	`decompress(File inFile, Compression compression)`	Decompresses a given file, leaving the original
`static void`	`decompressAll(File folder, Compression compression, int parallelism)`	Decompresses all files in the given folder, deleting the originals File names are removed the relevant extension (.gz/.zst), and if not found, the name is appended with ".decompressed".
`static void`	`deleteFile(File f, org.slf4j.Logger logger)`	Deletes a file/folder, ignoring failures.
`static void`	`deleteFiles(File... files)`	Deletes a set of files/folders, ignoring failures.
`static void`	`deleteFiles(org.slf4j.Logger logger, File... files)`	Deletes a set of files/folders, ignoring failures.
`static InputStream`	`getCompressionInputStream(InputStream is, Compression compression)`
`static OutputStream`	`getCompressionOutputStream(OutputStream os, Compression compression)`
`static OutputStream`	`getCompressionOutputStream(OutputStream os, Compression compression, int compressionLevel)`
`static String`	`getDotlessExtension(String name)`
`static String`	`getExtension(String name)`
`static BufferedInputStream`	`getInputStream(File f, FileReadOptions options)`	Creates an input stream that reads from a file, using the given `FileReadOptions`.
`static BufferedInputStream`	`getInputStream(InputStream is, FileReadOptions options)`	Wraps an input stream, adding the features defined by the given `FileReadOptions`.
`static InputStream`	`getInputStreamFromClasspath(String path)`	Return the input stream of the given resource path
`static net.minidev.json.JSONObject`	`getJSONFromClasspath(String filename)`	Utility for loading JSON objects from classpath files
`static net.minidev.json.JSONObject`	`getJSONFromFile(File file)`
`static net.minidev.json.JSONObject`	`getJSONFromInpuStream(InputStream is)`
`static List<net.minidev.json.JSONObject>`	`getJSONListFromClasspath(String filename)`	Utility for loading a list of JSON objects from classpath files, assuming that every line has one JSON object.
`static List<net.minidev.json.JSONObject>`	`getJSONListFromFile(File file)`	Utility for loading a list of JSON objects from a file, assuming that every line has one JSON object.
`static List<String>`	`getLinesFromClasspath(String filename)`	Utility for loading the lines of a classpath file (UTF8).
`static List<String>`	`getLinesFromFile(File file)`	Utility for loading the lines of a local text file (UTF8).
`static List<String>`	`getLinesFromFile(File file, Charset charset, FileReadOptions options)`	Utility for loading the lines of a local text file
`static Set<String>`	`getLinesFromFileAsSet(File file)`	Utility for loading the lines of a local text file (UTF8) into a set
`static Set<String>`	`getLinesFromFileAsSet(File file, Charset charset, FileReadOptions options)`	Utility for loading the lines of a local text file into a set
`static List<String>`	`getListFromReader(Reader reader)`	Utility for loading the lines from a reader
`static BufferedOutputStream`	`getOutputStream(File f, FileWriteOptions options)`	Creates an output stream that writes into a file, using the given `FileWriteOptions`.
`static BufferedOutputStream`	`getOutputStream(OutputStream os, FileWriteOptions options)`	Wraps an output stream, adding it options by the given `FileWriteOptions`.
`static BufferedReader`	`getReader(File f)`	Creates a new buffered reader from a given file, using UTF8.
`static BufferedReader`	`getReader(File f, Charset charset)`	Creates a new buffered reader from a given file.
`static BufferedReader`	`getReader(File f, Charset charset, FileReadOptions options)`	Creates a new buffered reader from a given file.
`static BufferedReader`	`getReader(File f, FileReadOptions options)`	Creates a new buffered reader from a given file, using UTF8.
`static BufferedReader`	`getReader(InputStream is)`	Wraps an input stream and converts it to a reader.
`static BufferedReader`	`getReader(InputStream is, Charset charset, FileReadOptions options)`	Wraps an input stream and converts it to a reader.
`static BufferedReader`	`getReaderFromClasspath(String path)`	Creates a new buffered reader from a given file, using UTF8.
`static BufferedReader`	`getReaderFromClasspath(String path, Charset charset)`	Creates a new buffered reader from a given file.
`static BufferedReader`	`getReaderFromClasspath(String path, Charset charset, FileReadOptions options)`	Creates a new buffered reader from a given file.
`static BufferedReader`	`getReaderFromClasspath(String path, FileReadOptions options)`	Creates a new buffered reader from a given file, using UTF8.
`static Set<String>`	`getSetFromReader(Reader reader)`	Utility for loading the lines from a reader, into a deduped set
`static String`	`getStringFromClasspath(String filename)`	Utility for loading string from classpath files
`static File`	`getSystemDefaultTmpFolder()`
`static long`	`getTotalSizeRecursive(File folder)`
`static BufferedWriter`	`getWriter(File f)`	Creates a new buffered writer for a given file, using UTF8 and default file writing settings (See `FileWriteOptions`).
`static BufferedWriter`	`getWriter(File f, Charset charset)`	Creates a new buffered writer for a given file, using default file writing settings (See `FileWriteOptions`).
`static BufferedWriter`	`getWriter(File f, Charset charset, FileWriteOptions options)`	Creates a new buffered writer for a given file.
`static BufferedWriter`	`getWriter(File f, FileWriteOptions options)`	Creates a new buffered writer for a given file, using UTF8.
`static BufferedWriter`	`getWriter(OutputStream os, Charset charset, FileWriteOptions options)`	Wraps a gives output stream, setting the requires write options It's recommended to call this method from within a try-with-resources block.
`static File`	`gunzip(File inFile)`	Decompresses a given file (from gz), leaving the original
`static File`	`gzip(File inFile)`	Compresses a given file (to gz), leaving the original
`static String`	`joinPaths(String prefixPath, String suffixPath)`
`static int`	`lineCount(File source)`	Counts lines in a file, which is assumed to be UTF8, not compressed.
`static int`	`lineCount(File source, FileReadOptions options)`
`static List<List<String>>`	`readCSV(File file)`	Reads and parses a CSV file with no headers.
`static List<List<String>>`	`readCSV(File file, Charset charset, FileReadOptions options)`	Reads and parses a CSV file with no headers.
`static List<List<String>>`	`readCSV(File file, FileReadOptions options)`	Reads and parses a CSV file with no headers.
`static List<List<String>>`	`readCSV(Reader csvReader)`	Reads and parses a CSV file with no headers.
`static String`	`removeCSVExtension(String fileName)`
`static String`	`removeDotlessExtension(String name)`
`static String`	`removeExtension(String name)`
`static void`	`sampleLines(File srcFile, int srcSize, File dstFile, int toSample)`	Uses a streaming sampling algorithm to select M lines from a given file, guaranteeing equal probability for all subsets of the requested sample size (See https://eyalsch.wordpress.com/2010/04/01/random-sample/ for details).
`static void`	`saveFileHead(File file, int lineCountToCopy, File outputFile)`	Saves the head of a given file in another new file/
`static void`	`sort(File srcDir, FilenameFilter fnameFilter, File trgt, File tmpDir, int memLimit)`	Same as {@link this#sort(File, FilenameFilter, File, File, int)}, but enables to supply a `FilenameFilter` to exclude files from the provided directory from being sorted.
`static void`	`sort(File src, File trgt, File tmpDir, int memLimit)`	Serves for sorting large files on the file system, limiting the memory used in the process.
`static void`	`validateFolderNotEmpty(File folder)`	throws exception if folder is invalid or empty.
`static <T> void`	`writeCSV(Collection<T> lines, File f, Function<T,Object[]> toLineTransformer)`	Writes CSV file with no headers.
`static <T> void`	`writeCSV(Collection<T> lines, File f, Function<T,Object[]> toLineTransformer, FileWriteOptions options)`	Writes CSV file with no headers.
`static <T> void`	`writeCSV(Iterator<T> iterator, File file, Function<T,Object[]> toLineTransformer, FileWriteOptions options, String... headers)`	Writes items from iterator into the given csv file.
`static void`	`writeCSV(List<List<String>> lines, File f)`	Writes CSV file with no headers.
`static void`	`writeJSONListToFile(List<net.minidev.json.JSONObject> jsonList, File file)`
`static void`	`writeJSONToFile(net.minidev.json.JSONObject json, File file)`
`static void`	`writeLines(Collection<String> lines, File f)`	Writes the given lines to a file, using default file write options
`static void`	`writeLines(Collection<String> lines, File f, FileWriteOptions options)`	Writes the given lines to a file.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - CSV_GZ_EXTENSION
```
public static final String CSV_GZ_EXTENSION
```
    See Also:
    
    Constant Field Values
  - CSV_ZSTD_EXTENSION
```
public static final String CSV_ZSTD_EXTENSION
```
    See Also:
    
    Constant Field Values
  - ZSTD_EXTENSION
```
public static final String ZSTD_EXTENSION
```
  - CSV_EXTENSION
```
public static final String CSV_EXTENSION
```
    See Also:
    
    Constant Field Values
  - NDJSON_EXTENSION
```
public static final String NDJSON_EXTENSION
```
    See Also:
    
    Constant Field Values
  - GZ_EXTENSION
```
public static final String GZ_EXTENSION
```
  - UTF8
```
public static final Charset UTF8
```
- Constructor Detail
  - FileUtils
```
public FileUtils()
```
- Method Detail
  - getLinesFromClasspath
```
public static List<String> getLinesFromClasspath(String filename)
                                          throws IOException
```
    Utility for loading the lines of a classpath file (UTF8).
    
    Parameters:
    
    filename - A filename (in classpath). Must refer to a textual file in UTF8.
    
    Returns:
    
    The list of strings, each representing a line
    
    Throws:
    
    IOException
  - getLinesFromFile
```
public static List<String> getLinesFromFile(File file,
                                            Charset charset,
                                            FileReadOptions options)
                                     throws IOException
```
    Utility for loading the lines of a local text file
    
    Parameters:
    
    file - The file to read the lines from
    
    charset - The charset the text file is encoded with
    
    options - the file reading options
    
    Returns:
    
    The list of strings, each representing a line
    
    Throws:
    
    IOException
  - getLinesFromFile
```
public static List<String> getLinesFromFile(File file)
                                     throws IOException
```
    Utility for loading the lines of a local text file (UTF8).
    
    Parameters:
    
    file - The file to read the lines from (UTF8)
    
    Returns:
    
    The list of strings, each representing a line
    
    Throws:
    
    IOException
  - getLinesFromFileAsSet
```
public static Set<String> getLinesFromFileAsSet(File file,
                                                Charset charset,
                                                FileReadOptions options)
                                         throws IOException
```
    Utility for loading the lines of a local text file into a set
    
    Parameters:
    
    file - The file to read the lines from
    
    charset - The charset the text file is encoded with
    
    options - the file reading options
    
    Returns:
    
    The set of strings, each representing a unique line value
    
    Throws:
    
    IOException
  - getLinesFromFileAsSet
```
public static Set<String> getLinesFromFileAsSet(File file)
                                         throws IOException
```
    Utility for loading the lines of a local text file (UTF8) into a set
    
    Parameters:
    
    file - The file to read the lines from (UTF8)
    
    Returns:
    
    The set of strings, each representing a unique line value
    
    Throws:
    
    IOException
  - getListFromReader
```
public static List<String> getListFromReader(Reader reader)
                                      throws IOException
```
    Utility for loading the lines from a reader
    
    Parameters:
    
    reader - The reader to read from. No need to be a buffered reader. Closed at the end of this call, regardless of IO exceptions.
    
    Returns:
    
    The list of strings, each representing a line
    
    Throws:
    
    IOException
  - getSetFromReader
```
public static Set<String> getSetFromReader(Reader reader)
                                    throws IOException
```
    Utility for loading the lines from a reader, into a deduped set
    
    Parameters:
    
    reader - The reader to read from. No need to be a buffered reader. Closed at the end of this call, regardless of IO exceptions.
    
    Returns:
    
    The set of strings, each representing a line
    
    Throws:
    
    IOException
  - getJSONFromClasspath
```
public static net.minidev.json.JSONObject getJSONFromClasspath(String filename)
                                                        throws IOException,
                                                               net.minidev.json.parser.ParseException
```
    Utility for loading JSON objects from classpath files
    
    Parameters:
    
    filename - A filename (in classpath)
    
    Returns:
    
    The json object as read from the given file
    
    Throws:
    
    IOException
    
    net.minidev.json.parser.ParseException
  - getJSONListFromClasspath
```
public static List<net.minidev.json.JSONObject> getJSONListFromClasspath(String filename)
                                                                  throws IOException,
                                                                         net.minidev.json.parser.ParseException
```
    Utility for loading a list of JSON objects from classpath files, assuming that every line has one JSON object.
    
    Parameters:
    
    filename - A filename (in classpath)
    
    Returns:
    
    The list of json objects, one per line in the file
    
    Throws:
    
    IOException
    
    net.minidev.json.parser.ParseException
  - getStringFromClasspath
```
public static String getStringFromClasspath(String filename)
                                     throws IOException
```
    Utility for loading string from classpath files
    
    Parameters:
    
    filename - A filename (in classpath)
    
    Returns:
    
    The string as read from the given file
    
    Throws:
    
    IOException
  - getJSONFromInpuStream
```
public static net.minidev.json.JSONObject getJSONFromInpuStream(InputStream is)
                                                         throws IOException,
                                                                net.minidev.json.parser.ParseException
```
    Parameters:
    
    is - An input stream to read the json from. Expected to have a single valid json object. The stream is closed by this method.
    
    Returns:
    
    The json object as read from the given stream
    
    Throws:
    
    IOException
    
    net.minidev.json.parser.ParseException
  - getJSONFromFile
```
public static net.minidev.json.JSONObject getJSONFromFile(File file)
                                                   throws IOException,
                                                          net.minidev.json.parser.ParseException
```
    Parameters:
    
    file - A file to read as json. Expected to have one valid json object.
    
    Returns:
    
    The json object as read from the given file
    
    Throws:
    
    IOException
    
    net.minidev.json.parser.ParseException
  - getJSONListFromFile
```
public static List<net.minidev.json.JSONObject> getJSONListFromFile(File file)
                                                             throws IOException,
                                                                    net.minidev.json.parser.ParseException
```
    Utility for loading a list of JSON objects from a file, assuming that every line has one JSON object.
    
    Parameters:
    
    file - The file to read from
    
    Returns:
    
    The list of json objects, each one read from one line in the file
    
    Throws:
    
    IOException
    
    net.minidev.json.parser.ParseException
  - writeJSONToFile
```
public static void writeJSONToFile(net.minidev.json.JSONObject json,
                                   File file)
                            throws IOException
```
    Parameters:
    
    json - The json object to write
    
    file - A file to write the json to. The file is being overridden.
    
    Throws:
    
    IOException
  - writeJSONListToFile
```
public static void writeJSONListToFile(List<net.minidev.json.JSONObject> jsonList,
                                       File file)
                                throws IOException,
                                       net.minidev.json.parser.ParseException
```
    Parameters:
    
    jsonList - The list of json objects to write, one per line
    
    file - A file to write the json objects to
    
    Throws:
    
    IOException
    
    net.minidev.json.parser.ParseException
  - readCSV
```
public static List<List<String>> readCSV(File file)
                                  throws IOException
```
    Reads and parses a CSV file with no headers. Supports null values.
    
    Parameters:
    
    file - The CSV file to read from
    
    Returns:
    
    A list of lines, each composed of a list of parsed columns
    
    Throws:
    
    IOException
  - readCSV
```
public static List<List<String>> readCSV(File file,
                                         Charset charset,
                                         FileReadOptions options)
                                  throws IOException
```
    Reads and parses a CSV file with no headers. Supports null values.
    
    Parameters:
    
    file - The CSV file to read from
    
    options - (allows reading compressed CSVs for example)
    
    Returns:
    
    A list of lines, each composed of a list of parsed columns
    
    Throws:
    
    IOException
  - readCSV
```
public static List<List<String>> readCSV(Reader csvReader)
                                  throws IOException
```
    Reads and parses a CSV file with no headers. Supports null values.
    
    Parameters:
    
    csvReader - The CSV file reader
    
    Returns:
    
    A list of lines, each composed of a list of parsed columns
    
    Throws:
    
    IOException
  - readCSV
```
public static List<List<String>> readCSV(File file,
                                         FileReadOptions options)
                                  throws IOException
```
    Reads and parses a CSV file with no headers. Supports null values.
    
    Parameters:
    
    file - The CSV file to read from
    
    options - (allows reading compressed CSVs for example)
    
    Returns:
    
    A list of lines, each composed of a list of parsed columns
    
    Throws:
    
    IOException
  - writeCSV
```
public static void writeCSV(List<List<String>> lines,
                            File f)
                     throws IOException
```
    Writes CSV file with no headers. Supports null values.
    
    Parameters:
    
    lines - the lines to write. The iteration order defines the line write order.
    
    f - The file to write to
    
    Throws:
    
    IOException
  - writeCSV
```
public static <T> void writeCSV(Collection<T> lines,
                                File f,
                                Function<T,Object[]> toLineTransformer,
                                FileWriteOptions options)
                         throws IOException
```
    Writes CSV file with no headers. Supports null values. receives the toLineTransformer and applies it on each line.
    
    Parameters:
    
    lines - the lines to write. The iteration order defines the line write order.
    
    toLineTransformer - transformer of each object into csv columns
    
    f - The file to write to
    
    options - The file writing options
    
    Throws:
    
    IOException
  - writeCSV
```
public static <T> void writeCSV(Iterator<T> iterator,
                                File file,
                                Function<T,Object[]> toLineTransformer,
                                FileWriteOptions options,
                                String... headers)
                         throws IOException
```
    Writes items from iterator into the given csv file. Including headers.
    
    Type Parameters:
    
    T - the entity type
    
    Parameters:
    
    iterator - the objects to write in each row
    
    file - the file to write
    
    toLineTransformer - transformer of each object into csv columns
    
    options - file write options
    
    headers - the csv file headers. optional - if null/empty - ignored
    
    Throws:
    
    IOException - on failure
  - writeCSV
```
public static <T> void writeCSV(Collection<T> lines,
                                File f,
                                Function<T,Object[]> toLineTransformer)
                         throws IOException
```
    Writes CSV file with no headers. Supports null values. receives the toLineTransformer and applies it on each line.
    
    Parameters:
    
    lines - the lines to write. The iteration order defines the line write order.
    
    f - The file to write to
    
    Throws:
    
    IOException
  - writeLines
```
public static void writeLines(Collection<String> lines,
                              File f,
                              FileWriteOptions options)
                       throws IOException
```
    Writes the given lines to a file.
    
    Parameters:
    
    lines - the lines to write. The iteration order defines the line write order.
    
    f - The file to write to
    
    options - The file writing options
    
    Throws:
    
    IOException
  - writeLines
```
public static void writeLines(Collection<String> lines,
                              File f)
                       throws IOException
```
    Writes the given lines to a file, using default file write options
    
    Parameters:
    
    lines - the lines to write. The iteration order defines the line write order.
    
    f - The file to write to
    
    Throws:
    
    IOException
  - createFolder
```
public static File createFolder(String folderPath)
                         throws IOException
```
    creates a folder, or keeps it if exists
    
    Parameters:
    
    folderPath - - path (including the name) of the folder
    
    Returns:
    
    The new created folder
    
    Throws:
    
    IOException
  - createFolder
```
public static File createFolder(File parentFolder,
                                String folderPath)
                         throws IOException
```
    creates a folder
    
    Parameters:
    
    parentFolder - the parent folder that should contain the folder
    
    folderPath - path (including the name) of the folder
    
    Returns:
    
    The new requested folder (existing or created), after verifying its existence
    
    Throws:
    
    IOException
  - sort
```
public static void sort(File src,
                        File trgt,
                        File tmpDir,
                        int memLimit)
                 throws IOException,
                        InterruptedException
```
    Serves for sorting large files on the file system, limiting the memory used in the process. NOTE: this method is not cross-platform, and uses linux' sort command. Use with care.
    
    Throws:
    
    IOException
    
    InterruptedException
  - sort
```
public static void sort(File srcDir,
                        FilenameFilter fnameFilter,
                        File trgt,
                        File tmpDir,
                        int memLimit)
                 throws IOException,
                        InterruptedException
```
    Same as {@link this#sort(File, FilenameFilter, File, File, int)}, but enables to supply a FilenameFilter to exclude files from the provided directory from being sorted.
    
    Parameters:
    
    srcDir - The file/folder to sort. The file/s are assumed to be CSV, and lines are sorted lexicographically. If a folder is used, all files inside it are sorted as into one output file. Lines are being deduped.
    
    fnameFilter - a predicate for including files in the sort operation
    
    trgt - The target file to write to
    
    tmpDir - The temp folder to use for intermediate sorting results. Note that a new temp subfolder is created under this folder, and finally is cleaned up.
    
    memLimit - The limit of memory usage, in megabytes
    
    Throws:
    
    IOException
    
    InterruptedException
  - lineCount
```
public static int lineCount(File source,
                            FileReadOptions options)
                     throws IOException
```
    Parameters:
    
    source - The file to examine
    
    options - File reading options
    
    Returns:
    
    The number of lines in the file
    
    Throws:
    
    IOException
  - lineCount
```
public static int lineCount(File source)
                     throws IOException
```
    Counts lines in a file, which is assumed to be UTF8, not compressed.
    
    Parameters:
    
    source - The file to examine
    
    Returns:
    
    The number of lines in the file
    
    Throws:
    
    IOException
  - joinPaths
```
public static String joinPaths(String prefixPath,
                               String suffixPath)
```
    Parameters:
    
    prefixPath - The path to serve as a prefix. May be empty. May end with '/'.
    
    suffixPath - A path to serve as a suffix. May be empty. May start with '/'.
    
    Returns:
    
    The concatenated path, using '/' as path separator.
  - deleteFile
```
public static void deleteFile(File f,
                              org.slf4j.Logger logger)
```
    Deletes a file/folder, ignoring failures. In case of a failure reports to the log.
    
    Parameters:
    
    f - The file to delete. May be null. May be a folder. In case of a folder, the complete folder is deleted, recursively.
    
    logger - The logger to log to in case deletion fails (as warning). Use null for no logging.
  - deleteFiles
```
public static void deleteFiles(org.slf4j.Logger logger,
                               File... files)
```
    Deletes a set of files/folders, ignoring failures.
    
    Parameters:
    
    logger - The logger to log to in case deletion fails (as warning). Use null for no logging.
    
    files - The files to delete. Null files are ignored. File objects may be folders - In this case, the complete folder is deleted, recursively.
  - deleteFiles
```
public static void deleteFiles(File... files)
```
    Deletes a set of files/folders, ignoring failures.
    
    Parameters:
    
    files - The files to delete. Null files are ignored. File objects may be folders - In this case, the complete folder is deleted, recursively.
  - sampleLines
```
public static void sampleLines(File srcFile,
                               int srcSize,
                               File dstFile,
                               int toSample)
                        throws IOException
```
    Uses a streaming sampling algorithm to select M lines from a given file, guaranteeing equal probability for all subsets of the requested sample size (See https://eyalsch.wordpress.com/2010/04/01/random-sample/ for details). Time complexity: Linear in size of the input file Space complexity: O(1)
    
    Parameters:
    
    srcFile - The file to sample lines from. Assumed to be textual, UTF8.
    
    srcSize - The number of lines in srcFile.
    
    dstFile - The destination file to contain the produced sample
    
    toSample - The number of lines to sample.
    
    Throws:
    
    IOException - In case of read/write error
  - saveFileHead
```
public static void saveFileHead(File file,
                                int lineCountToCopy,
                                File outputFile)
                         throws IOException
```
    Saves the head of a given file in another new file/
    
    Parameters:
    
    file - The input text file
    
    lineCountToCopy - The number of lines to copy from the input file. Less lines may be copied if the file line count is lower than this number.
    
    outputFile - The output file
    
    Throws:
    
    IOException
  - gzip
```
public static File gzip(File inFile)
                 throws IOException
```
    Compresses a given file (to gz), leaving the original
    
    Parameters:
    
    inFile - The file to compress
    
    Returns:
    
    The new compressed file, created in the same folder, with the same name as the original, but with the ".gz" suffix
    
    Throws:
    
    IOException - If reading/writing fails
  - compress
```
public static File compress(File inFile,
                            Compression compression)
                     throws IOException
```
    Compresses a given file, leaving the original. Uses the default compression level of the chosen compression.
    
    Parameters:
    
    inFile - The file to compress
    
    compression - The compression to use. Using Compression.NONE does nothing and returns the input file.
    
    Returns:
    
    The new compressed file, created in the same folder, with the same name as the original, but with the suffix corresponding to the selected compression.
    
    Throws:
    
    IOException - If reading/writing fails
  - compress
```
public static File compress(File inFile,
                            Compression compression,
                            int compressionLevel)
                     throws IOException
```
    Compresses a given file, leaving the original
    
    Parameters:
    
    inFile - The file to compress
    
    compression - The compression to use. Using Compression.NONE does nothing and returns the input file.
    
    compressionLevel - The compression level to use. Specific to the chosen compression scheme and should be used with caution.
    
    Returns:
    
    The new compressed file, created in the same folder, with the same name as the original, but with the suffix corresponding to the selected compression.
    
    Throws:
    
    IOException - If reading/writing fails
  - compressAll
```
public static void compressAll(File folder,
                               Compression compression,
                               int parallelism)
                        throws IOException
```
    Compresses all files in the given folder, deleting the originals Original file names are appended the corresponding compression suffix (.gz/.zst).
    
    Parameters:
    
    folder - The input folder
    
    compression - The compression to use. NONE is illegal.
    
    parallelism - The number of threads to use
    
    Throws:
    
    IOException
  - compressAll
```
public static void compressAll(File folder,
                               Compression compression,
                               int compressionLevel,
                               int parallelism)
                        throws IOException
```
    Compresses all files in the given folder, deleting the originals Original file names are appended the corresponding compression suffix (.gz/.zst).
    
    Parameters:
    
    folder - The input folder
    
    compression - The compression to use. NONE is illegal.
    
    compressionLevel - The compression level to use. Specific to the chosen compression scheme and should be used with caution.
    
    parallelism - The number of threads to use
    
    Throws:
    
    IOException - in case of IO error or if the thread is interrupted
  - gunzip
```
public static File gunzip(File inFile)
                   throws IOException
```
    Decompresses a given file (from gz), leaving the original
    
    Parameters:
    
    inFile - The file to decompress
    
    Returns:
    
    The new decompressed file, in the same folder as the input file. The name will be the same as the original, with the ".gz" suffix removed. In case of no such suffix of the original file, the suffix ".decompressed" is added to the target file
    
    Throws:
    
    IOException - If reading/writing fails
  - decompress
```
public static File decompress(File inFile,
                              Compression compression)
                       throws IOException
```
    Decompresses a given file, leaving the original
    
    Parameters:
    
    inFile - The file to decompress
    
    compression - The compression to assume
    
    Returns:
    
    The new decompressed file, in the same folder as the input file. The name will be the same as the original, with the corresponding suffix removed (.gz, or .zst) In case of no such suffix of the original file, the suffix ".decompressed" is added to the target file.
    
    Throws:
    
    IOException - If reading/writing fails
  - decompressAll
```
public static void decompressAll(File folder,
                                 Compression compression,
                                 int parallelism)
                          throws IOException
```
    Decompresses all files in the given folder, deleting the originals File names are removed the relevant extension (.gz/.zst), and if not found, the name is appended with ".decompressed".
    
    Parameters:
    
    folder - The input folder
    
    compression - The compression to assume. NONE is illegal.
    
    parallelism - The number of threads to use
    
    Throws:
    
    IOException - in case of IO error or if the thread is interrupted
  - areIdentical
```
public static boolean areIdentical(File file1,
                                   File file2)
                            throws IOException
```
    Compares two given files
    
    Parameters:
    
    file1 - File #1
    
    file2 - File #2
    
    Returns:
    
    True if and only if the byte sequences of the two files are identical
    
    Throws:
    
    IOException
  - createTempFile
```
public static File createTempFile(String prefix,
                                  String suffix,
                                  File folder)
                           throws IOException
```
    Creates a unique temp file in the given folder. The file is deleted automatically when the JVM exits.
    
    Parameters:
    
    prefix - The name prefix of the temp file. Must be at least 3 char long.
    
    suffix - The name suffix of the temp file (e.g. ".csv").
    
    folder - The folder where to create the temp file, or null for default temp folder.
    
    Returns:
    
    A new temp file in the given folder. The file is set to be deleted at JVM shutdown, but it's recommended to delete it explicitly when not used anymore.
    
    Throws:
    
    IOException
  - createTempFile
```
public static File createTempFile(String prefix,
                                  String suffix)
                           throws IOException
```
    Creates a unique temp file in the system's default tmp folder. The file is deleted automatically when the JVM exits.
    
    Parameters:
    
    prefix - The name prefix of the temp file. Must be at least 3 char long. Must not include path separators.
    
    prefix - The name suffix of the temp file (e.g. ".csv").
    
    Returns:
    
    A new temp file in the system's temp folder. The file is set to be deleted at JVM shutdown, but it's recommended to delete it explicitly when not used anymore.
    
    Throws:
    
    IOException
  - createUniqueFile
```
public static File createUniqueFile(String prefix,
                                    String suffix,
                                    File folder)
                             throws IOException
```
    Creates a unique file in the given folder. The file is not deleted automatically when the JVM exits.
    
    Parameters:
    
    prefix - The name prefix of the temp file. Must be at least 3 char long. Must not include path separators.
    
    suffix - The name suffix of the temp file (e.g. ".csv").
    
    folder - The folder where to create the temp file
    
    Returns:
    
    A new file in the given folder
    
    Throws:
    
    IOException
  - createUniqueFile
```
public static File createUniqueFile(String prefix,
                                    String suffix)
                             throws IOException
```
    Creates a unique file in the system's default tmp folder. The file is not deleted automatically when the JVM exits.
    
    Parameters:
    
    prefix - The name prefix of the temp file. Must be at least 3 char long. Must not include path separators.
    
    prefix - The name suffix of the temp file (e.g. ".csv").
    
    Returns:
    
    A new file in the system's temp folder
    
    Throws:
    
    IOException
  - createTempFolder
```
public static File createTempFolder(String prefix,
                                    File parentFolder)
                             throws IOException
```
    creates a temp folder under a given parent folder
    
    Parameters:
    
    prefix - The name prefix for the temp folder
    
    parentFolder - The parent folder under which to create the temp folder
    
    Returns:
    
    A new temp folder under the given parent folder. The folder is set to be deleted at JVM shutdown
    
    Throws:
    
    IOException
  - getSystemDefaultTmpFolder
```
public static File getSystemDefaultTmpFolder()
```
    Returns:
    
    the tmp folder on the local machine
  - createUniqueFolder
```
public static File createUniqueFolder(String prefix,
                                      File parentFolder)
                               throws IOException
```
    creates a unique folder under a given parent folder
    
    Parameters:
    
    prefix - The name prefix for the folder
    
    parentFolder - The parent folder under which to create the folder
    
    Returns:
    
    A new folder with unique name under the given parent folder. The folder is not set to be deleted at JVM shutdown
    
    Throws:
    
    IOException
  - createTempFolder
```
public static File createTempFolder(String prefix)
                             throws IOException
```
    creates a temp folder under the system's default tmp folder
    
    Parameters:
    
    prefix - The name prefix for the temp folder
    
    Returns:
    
    A new temp folder under the system's tmp folder. The folder is set to be deleted at JVM shutdown, provided that it's empty or all files in it are also created as temporary.
    
    Throws:
    
    IOException
  - createUniqueFolder
```
public static File createUniqueFolder(String prefix)
                               throws IOException
```
    creates a unique folder under the system's default tmp folder
    
    Parameters:
    
    prefix - The name prefix for the folder
    
    Returns:
    
    A new folder under the system's tmp folder. The folder is not set to be deleted at JVM shutdown
    
    Throws:
    
    IOException
  - getOutputStream
```
public static BufferedOutputStream getOutputStream(OutputStream os,
                                                   FileWriteOptions options)
                                            throws IOException
```
    Wraps an output stream, adding it options by the given FileWriteOptions.
    
    Parameters:
    
    os - The stream to wrap
    
    options - The write options
    
    Returns:
    
    The resulting output stream (buffered)
    
    Throws:
    
    IOException
  - getOutputStream
```
public static BufferedOutputStream getOutputStream(File f,
                                                   FileWriteOptions options)
                                            throws IOException
```
    Creates an output stream that writes into a file, using the given FileWriteOptions.
    
    Parameters:
    
    f - The file to write to
    
    options - The write options
    
    Returns:
    
    The resulting output stream (buffered)
    
    Throws:
    
    IOException
  - getInputStream
```
public static BufferedInputStream getInputStream(InputStream is,
                                                 FileReadOptions options)
                                          throws IOException
```
    Wraps an input stream, adding the features defined by the given FileReadOptions.
    
    Parameters:
    
    is - The input stream to wrap
    
    options - The read options
    
    Returns:
    
    The resulting input stream (Buffered)
    
    Throws:
    
    IOException
  - getInputStream
```
public static BufferedInputStream getInputStream(File f,
                                                 FileReadOptions options)
                                          throws IOException
```
    Creates an input stream that reads from a file, using the given FileReadOptions.
    
    Parameters:
    
    f - The file to read from
    
    options - The read options
    
    Returns:
    
    The resulting input stream (Buffered)
    
    Throws:
    
    IOException
  - getWriter
```
public static BufferedWriter getWriter(OutputStream os,
                                       Charset charset,
                                       FileWriteOptions options)
                                throws IOException
```
    Wraps a gives output stream, setting the requires write options It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    os - The output stream to wrap
    
    charset - The character encoding to use
    
    options - The write options
    
    Returns:
    
    The new buffered writer. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getWriter
```
public static BufferedWriter getWriter(File f,
                                       Charset charset,
                                       FileWriteOptions options)
                                throws IOException
```
    Creates a new buffered writer for a given file. It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    f - The file
    
    charset - The character encoding to use
    
    options - The file writing options
    
    Returns:
    
    The new buffered writer. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getWriter
```
public static BufferedWriter getWriter(File f,
                                       FileWriteOptions options)
                                throws IOException
```
    Creates a new buffered writer for a given file, using UTF8. It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    f - The file
    
    options - The file writing options
    
    Returns:
    
    The new buffered writer. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getWriter
```
public static BufferedWriter getWriter(File f,
                                       Charset charset)
                                throws IOException
```
    Creates a new buffered writer for a given file, using default file writing settings (See FileWriteOptions). It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    f - The file
    
    charset - The character encoding to use
    
    Returns:
    
    The new buffered writer. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getWriter
```
public static BufferedWriter getWriter(File f)
                                throws IOException
```
    Creates a new buffered writer for a given file, using UTF8 and default file writing settings (See FileWriteOptions). It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    f - The file
    
    Returns:
    
    The new buffered writer. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getCompressionInputStream
```
public static InputStream getCompressionInputStream(InputStream is,
                                                    Compression compression)
                                             throws IOException
```
    Parameters:
    
    is - The input stream to wrap
    
    compression - Compression of the data supplied by the given input stream
    
    Returns:
    
    The decompressing input stream
    
    Throws:
    
    IOException
  - getCompressionOutputStream
```
public static OutputStream getCompressionOutputStream(OutputStream os,
                                                      Compression compression)
                                               throws IOException
```
    Parameters:
    
    os - The output stream to wrap
    
    compression - The required compression to apply
    
    Returns:
    
    The compressing output stream
    
    Throws:
    
    IOException
  - getCompressionOutputStream
```
public static OutputStream getCompressionOutputStream(OutputStream os,
                                                      Compression compression,
                                                      int compressionLevel)
                                               throws IOException
```
    Parameters:
    
    os - Output stream
    
    compression - The required compression to apply
    
    compressionLevel - The compression level to use. Specific to the chosen compression scheme.
    
    Returns:
    
    The compressing output stream
    
    Throws:
    
    IOException
  - getReader
```
public static BufferedReader getReader(InputStream is,
                                       Charset charset,
                                       FileReadOptions options)
                                throws IOException
```
    Wraps an input stream and converts it to a reader. It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    is - The input stream
    
    charset - The character encoding to use
    
    options - The read options
    
    Returns:
    
    The new buffered reader. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getReader
```
public static BufferedReader getReader(InputStream is)
                                throws IOException
```
    Wraps an input stream and converts it to a reader. It's recommended to call this method from within a try-with-resources block. Assumes UTF8, no compression and default buffer size.
    
    Parameters:
    
    is - The input stream
    
    Returns:
    
    The new buffered reader. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getReader
```
public static BufferedReader getReader(File f,
                                       Charset charset,
                                       FileReadOptions options)
                                throws IOException
```
    Creates a new buffered reader from a given file. It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    f - The file
    
    charset - The character encoding to use
    
    options - The file read options
    
    Returns:
    
    The new buffered reader. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getReader
```
public static BufferedReader getReader(File f,
                                       FileReadOptions options)
                                throws IOException
```
    Creates a new buffered reader from a given file, using UTF8. It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    f - The file
    
    options - The file read options
    
    Returns:
    
    The new buffered reader. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getReader
```
public static BufferedReader getReader(File f,
                                       Charset charset)
                                throws IOException
```
    Creates a new buffered reader from a given file. It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    f - The file
    
    charset - The character encoding to use
    
    Returns:
    
    The new buffered reader. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getReader
```
public static BufferedReader getReader(File f)
                                throws IOException
```
    Creates a new buffered reader from a given file, using UTF8. It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    f - The file
    
    Returns:
    
    The new buffered reader. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getInputStreamFromClasspath
```
public static InputStream getInputStreamFromClasspath(String path)
```
    Return the input stream of the given resource path
    
    Parameters:
    
    path - the resource path
    
    Returns:
    
    resource's input stream
  - getReaderFromClasspath
```
public static BufferedReader getReaderFromClasspath(String path,
                                                    Charset charset,
                                                    FileReadOptions options)
                                             throws IOException
```
    Creates a new buffered reader from a given file. It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    path - The path in classpath
    
    charset - The character encoding to use
    
    options - The file read options
    
    Returns:
    
    The new buffered reader. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getReaderFromClasspath
```
public static BufferedReader getReaderFromClasspath(String path,
                                                    FileReadOptions options)
                                             throws IOException
```
    Creates a new buffered reader from a given file, using UTF8. It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    path - The path in classpath
    
    options - The file read options
    
    Returns:
    
    The new buffered reader. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getReaderFromClasspath
```
public static BufferedReader getReaderFromClasspath(String path,
                                                    Charset charset)
                                             throws IOException
```
    Creates a new buffered reader from a given file. It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    path - The path in classpath
    
    charset - The character encoding to use
    
    Returns:
    
    The new buffered reader. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - getReaderFromClasspath
```
public static BufferedReader getReaderFromClasspath(String path)
                                             throws IOException
```
    Creates a new buffered reader from a given file, using UTF8. It's recommended to call this method from within a try-with-resources block.
    
    Parameters:
    
    path - The path in classpath
    
    Returns:
    
    The new buffered reader. The caller should make sure to close it.
    
    Throws:
    
    IOException
  - validateFolderNotEmpty
```
public static void validateFolderNotEmpty(File folder)
                                   throws IOException
```
    throws exception if folder is invalid or empty.
    
    Throws:
    
    IOException - if folder is empty
  - getExtension
```
public static String getExtension(String name)
```
    Parameters:
    
    name - A file name
    
    Returns:
    
    The file extension. The extension is defined here as the suffix starting with the first '.'. If none, null is returned.
  - removeExtension
```
public static String removeExtension(String name)
```
    Parameters:
    
    name - A file name
    
    Returns:
    
    The file name, with the extension removed, if found. The extension is defined as the suffix starting with the first '.'.
  - getDotlessExtension
```
public static String getDotlessExtension(String name)
```
    Parameters:
    
    name - A file name
    
    Returns:
    
    The file extension. The extension is defined here as the suffix starting with the last '.'. If none, null is returned.
  - removeDotlessExtension
```
public static String removeDotlessExtension(String name)
```
    Parameters:
    
    name - A file name
    
    Returns:
    
    The file name, with the extension removed, if found. The extension is defined here as the suffix starting with the last '.'.
  - removeCSVExtension
```
public static String removeCSVExtension(String fileName)
```
    Parameters:
    
    fileName - A file name. May include path.
    
    Returns:
    
    The same name, but with the CSV extension removed (either .csv or .csv.gz or .csv.zst)
  - copyFile
```
public static void copyFile(File src,
                            File dst)
                     throws IOException
```
    Copies a file from one location to the other
    
    Parameters:
    
    src - The file to copy
    
    dst - The destination file
    
    Throws:
    
    IOException
  - copyFileToFolder
```
public static void copyFileToFolder(File src,
                                    File dstFolder)
                             throws IOException
```
    Copies a file from one location to the other, keeping the filename
    
    Parameters:
    
    src - The file to copy
    
    dstFolder - The destination folder
    
    Throws:
    
    IOException
  - getTotalSizeRecursive
```
public static long getTotalSizeRecursive(File folder)
```
    Parameters:
    
    folder - A local folder
    
    Returns:
    
    The total size, in bytes, of all descendant files under the given folder
  - close
```
public static void close(Closeable... closeables)
                  throws IOException
```
    Closes the resources in the order they are provided. Tries to close as much as possible closeables and then throws exception if needs to. Any of the closeables may be null
    
    Parameters:
    
    closeables - the closeables that needs to be closed. Ignores null closeables inside the array.
    
    Throws:
    
    IOException - the IOException that aggregates all the closable IOExceptions
  - close
```
public static void close(Collection<? extends Closeable> closeables)
                  throws IOException
```
    Closes the resources in the order they are provided. Tries to close as much as possible closeables and then throws exception if needs to. Any of the closeables may be null
    
    Parameters:
    
    closeables - the closeables that needs to be closed. Ignores null closeables inside the array.
    
    Throws:
    
    IOException - the IOException that aggregates all the closable IOExceptions
  - close
```
public static void close(Closeable closeable)
                  throws IOException
```
    Closes the closeable.
    
    Parameters:
    
    closeable - the closeable that needs to be closed. May be null.
    
    Throws:
    
    IOException - if an I/O error occurs
  - closeSilently
```
public static void closeSilently(Closeable... closeables)
```
    Closes the given closeables, in a silent manner (ignoring IOExceptions)
    
    Parameters:
    
    closeables - the closeables that needs to be closed. Any of them may be null.
  - closeSilently
```
public static void closeSilently(Collection<? extends Closeable> closeables)
```
    Closes the given closeables, in a silent manner (ignoring IOExceptions)
    
    Parameters:
    
    closeables - the closeables that needs to be closed. Any of them may be null.

Class FileUtils

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

CSV_GZ_EXTENSION

CSV_ZSTD_EXTENSION

ZSTD_EXTENSION

CSV_EXTENSION

NDJSON_EXTENSION

GZ_EXTENSION

UTF8

Constructor Detail

FileUtils

Method Detail

getLinesFromClasspath

getLinesFromFile

getLinesFromFile

getLinesFromFileAsSet

getLinesFromFileAsSet

getListFromReader

getSetFromReader

getJSONFromClasspath

getJSONListFromClasspath

getStringFromClasspath

getJSONFromInpuStream

getJSONFromFile

getJSONListFromFile

writeJSONToFile

writeJSONListToFile

readCSV

readCSV

readCSV

readCSV

writeCSV

writeCSV

writeCSV

writeCSV

writeLines

writeLines

createFolder

createFolder

sort

sort

lineCount

lineCount

joinPaths

deleteFile

deleteFiles

deleteFiles

sampleLines

saveFileHead

gzip

compress

compress

compressAll

compressAll

gunzip

decompress

decompressAll

areIdentical

createTempFile

createTempFile

createUniqueFile

createUniqueFile

createTempFolder

getSystemDefaultTmpFolder

createUniqueFolder

createTempFolder

createUniqueFolder

getOutputStream

getOutputStream

getInputStream

getInputStream

getWriter

getWriter

getWriter

getWriter

getWriter