    All Packages  Class Hierarchy  This Package  Previous  Next  Index

# Class java.io.File

    java.lang.Object
       |
       +----java.io.File

public class File
extends Object
implements Serializable

This class represents a file name of the host file system. The file name can be relative or absolute. It must use the file name conventions of the host platform.

The intention is to provide an abstraction that deals with most of the system-dependent file name features such as the separator character, root, device name, etc. Not all features are currently fully implemented.

Note that whenever a file name or path is used it is assumed that the host's file name conventions are used.

##

pathSeparator
  The system dependent path separator string.
pathSeparatorChar
  The system dependent path separator character.
separator
  The system dependent file separator String.
separatorChar
  The system dependent file separator character.

##

File(File, String)
  Creates a File object (given a directory File object).
File(String)
  Creates a File object.
File(String, String)
  Creates a File object from the specified directory.

##

canRead()
  Returns a boolean indicating whether or not a readable file exists.
canWrite()
  Returns a boolean indicating whether or not a writable file exists.
delete()
  Deletes the specified file.
equals(Object)
  Compares this object against the specified object.
exists()
  Returns a boolean indicating whether or not a file exists.
getAbsolutePath()
  Gets the absolute path of the file.
getCanonicalPath()
  Gets the official, canonical path of the File.
getName()
  Gets the name of the file.
getParent()
  Gets the name of the parent directory.
getPath()
  Gets the path of the file.
hashCode()
  Computes a hashcode for the file.
isAbsolute()
  Returns a boolean indicating whether the file name is absolute.
isDirectory()
  Returns a boolean indicating whether or not a directory file exists.
isFile()
  Returns a boolean indicating whether or not a normal file exists.
lastModified()
  Returns the last modification time.
length()
  Returns the length of the file.
list()
  Lists the files in a directory.
list(FilenameFilter)
  Uses the specified filter to list files in a directory.
mkdir()
  Creates a directory and returns a boolean indicating the success of the creation.
mkdirs()
  Creates all directories in this path.
renameTo(File)
  Renames a file and returns a boolean indicating whether or not this method was successful.
toString()
  Returns a String object representing this file's path.

##

separator

      public final static String separator

  The system dependent file separator String.

separatorChar

      public final static char separatorChar

  The system dependent file separator character.

pathSeparator

      public final static String pathSeparator

  The system dependent path separator string.

pathSeparatorChar

      public final static char pathSeparatorChar

  The system dependent path separator character.

##

File

      public File(String path)

  Creates a File object.

  Parameters:
    path - the file path
  Throws: NullPointerException
    If the file path is equal to null.

File

      public File(String path,
                  String name)

  Creates a File object from the specified directory.

  Parameters:
    path - the directory path
    name - the file name

File

      public File(File dir,
                  String name)

  Creates a File object (given a directory File object).

  Parameters:
    dir - the directory
    name - the file name

##

getName

      public String getName()

  Gets the name of the file. This method does not include the directory.

  Returns:
    the file name.

getPath

      public String getPath()

  Gets the path of the file.

  Returns:
    the file path.

getAbsolutePath

      public String getAbsolutePath()

  Gets the absolute path of the file.

  Returns:
    the absolute file path.

getCanonicalPath

      public String getCanonicalPath() throws IOException

  Gets the official, canonical path of the File.

  Returns:
    canonical path

getParent

      public String getParent()

  Gets the name of the parent directory.

  Returns:
    the parent directory, or null if one is not found.

exists

      public boolean exists()

  Returns a boolean indicating whether or not a file exists.

canWrite

      public boolean canWrite()

  Returns a boolean indicating whether or not a writable file exists.

canRead

      public boolean canRead()

  Returns a boolean indicating whether or not a readable file exists.

isFile

      public boolean isFile()

  Returns a boolean indicating whether or not a normal file exists.

isDirectory

      public boolean isDirectory()

  Returns a boolean indicating whether or not a directory file exists.

isAbsolute

      public boolean isAbsolute()

  Returns a boolean indicating whether the file name is absolute.

lastModified

      public long lastModified()

  Returns the last modification time. The return value should only be used to compare modification dates. It is meaningless as an absolute time.

length

      public long length()

  Returns the length of the file.

mkdir

      public boolean mkdir()

  Creates a directory and returns a boolean indicating the success of the creation. Will return false if the directory already exists.

renameTo

      public boolean renameTo(File dest)

  Renames a file and returns a boolean indicating whether or not this method was successful.

  Parameters:
    dest - the new file name

mkdirs

      public boolean mkdirs()

  Creates all directories in this path. This method returns true if the target (deepest) directory was created, false if the target directory was not created (e.g., if it existed previously).

list

      public String[] list()

  Lists the files in a directory. Works only on directories.

  Returns:
    an array of file names. This list will include all files in the directory except the equivalent of "." and ".." .

list

      public String[] list(FilenameFilter filter)

  Uses the specified filter to list files in a directory.

  Parameters:
    filter - the filter used to select file names
  Returns:
    the filter selected files in this directory.
  See Also:
    FilenameFilter

delete

      public boolean delete()

  Deletes the specified file. Returns true if the file could be deleted.

hashCode

      public int hashCode()

  Computes a hashcode for the file.

  Overrides:
    hashCode in class Object

equals

      public boolean equals(Object obj)

  Compares this object against the specified object.

  Parameters:
    obj - the object to compare with
  Returns:
    true if the objects are the same; false otherwise.
  Overrides:
    equals in class Object

toString

      public String toString()

  Returns a String object representing this file's path.

  Overrides:
    toString in class Object

    All Packages  Class Hierarchy  This Package  Previous  Next  Index