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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.

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.

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.

  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.

  public File(String path,
              String name)

Creates a File object from the specified directory.

Parameters:

path - the directory path

name - the file name

  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.

  public String getPath()

Gets the path of the file.

Returns:

the file path.

  public String getAbsolutePath()

Gets the absolute path of the file.

Returns:

the absolute file path.

  public String getParent()

Gets the name of the parent directory.

Returns:

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

  public boolean exists()

Returns a boolean indicating whether or not a file exists.

  public boolean canWrite()

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

  public boolean canRead()

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

  public boolean isFile()

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

  public boolean isDirectory()

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

  public boolean isAbsolute()

Returns a boolean indicating whether the file name is absolute.

  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.

  public long length()

Returns the length of the file.

  public boolean mkdir()

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

  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

  public boolean mkdirs()

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

  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 ".." .

  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

  public boolean delete()

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

  public int hashCode()

Computes a hashcode for the file.

Overrides:

hashCode in class Object

  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

  public String toString()

Returns a String object representing this file's path.

Overrides:

toString in class Object

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