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Class java.io.File

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

public class File

extends Object

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.

Version:

1.34, 10/22/95

Author:

Jonathan Payne, Arthur van Hoff

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(String)

Creates a File object.

File(String, String)

Creates a File object from the specified directory.

File(File, String)

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

canRead()

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

canWrite()

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

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.

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 if 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.

  public final static String separator

The system dependent file separator String.

  public final static char separatorChar

The system dependent file separator character.

  public final static String pathSeparator

The system dependent path separator string.

  public final static char pathSeparatorChar

The system dependent path separator character.

  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

  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.

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 if the file name is absolute.

lastModified

  public long lastModified() throws IOException

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() throws IOException

Returns the length of the file.

mkdir

  public boolean mkdir() throws IOException

Creates a directory and returns a boolean indicating the success of the creation.

renameTo

  public boolean renameTo(File dest) throws IOException

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() throws IOException

Creates all directories in this path. This method returns true if all directories in this path are created.

list

  public String[] list() throws IOException

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) throws IOException

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

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

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