Interface FileSystem

All Known Implementing Classes:
BasedFileSystem, LocalFileSystem

public interface FileSystem
The FileSystem interface is an abstraction of a virtual file system. The similarities of its method names with with the methods of the java.io.File class are intentional.
Implementations of this interface expose a file system-like resource. File system-like resources include WebDAV-enabled servers, local file systems, and so forth.
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final String
    File separator
    static final char
    File separator character
  • Method Summary

    Modifier and Type
    Method
    Description
    void
    Close the file system.
    void
    createFolder(String folderPath)
    Creates the folder named by this path, including any necessary but nonexistent parent folders.
    void
    deleteFile(String filePath)
    Deletes the file denoted by this path.
    void
    deleteFolder(String folderPath)
    Deletes the folder denoted by this path.
    boolean
    exists(String path)
    Tests whether the file system entry denoted by this path exists.
    Returns an input stream of the contents of the file denoted by this path.
    Returns an output stream for writing bytes to the file denoted by this path.
    boolean
    Tests whether the file system entry denoted by this path has child entries.
    void
    Initialize the file system
    boolean
    isFile(String path)
    Tests whether the file system entry denoted by this path exists and is a file.
    boolean
    Tests whether the file system entry denoted by this path exists and is a folder.
    long
    Returns the time that the file system entry denoted by this path was last modified.
    long
    length(String filePath)
    Returns the length of the file denoted by this path.
    list(String folderPath)
    Returns an array of strings naming the files and folders in the folder denoted by this path.
    listFiles(String folderPath)
    Returns an array of strings naming the files in the folder denoted by this path.
    listFolders(String folderPath)
    Returns an array of strings naming the folders in the folder denoted by this path.
  • Field Details

  • Method Details

    • init

      void init() throws FileSystemException
      Initialize the file system
      Throws:
      FileSystemException - if the file system initialization fails
    • close

      void close() throws FileSystemException
      Close the file system. After calling this method, the file system is no longer accessible.
      Throws:
      FileSystemException
    • getInputStream

      InputStream getInputStream(String filePath) throws FileSystemException
      Returns an input stream of the contents of the file denoted by this path.
      Parameters:
      filePath - the path of the file.
      Returns:
      an input stream of the contents of the file.
      Throws:
      FileSystemException - if the file does not exist or if it cannot be read from
    • getOutputStream

      OutputStream getOutputStream(String filePath) throws FileSystemException
      Returns an output stream for writing bytes to the file denoted by this path. The file will be created if it doesn't exist. If the file exists, its contents will be overwritten.
      Parameters:
      filePath - the path of the file.
      Returns:
      an output stream for writing bytes to the file.
      Throws:
      FileSystemException - if the file cannot be written to or created
    • createFolder

      void createFolder(String folderPath) throws FileSystemException
      Creates the folder named by this path, including any necessary but nonexistent parent folders. Note that if this operation fails it may have succeeded in creating some of the necessary parent folders.
      Parameters:
      folderPath - the path of the folder to be created.
      Throws:
      FileSystemException - if a file system entry denoted by path already exists or if another error occurs.
    • exists

      boolean exists(String path) throws FileSystemException
      Tests whether the file system entry denoted by this path exists.
      Parameters:
      path - the path of a file system entry.
      Returns:
      true if the file system entry at path exists; false otherwise.
      Throws:
      FileSystemException
    • isFile

      boolean isFile(String path) throws FileSystemException
      Tests whether the file system entry denoted by this path exists and is a file.
      Parameters:
      path - the path of a file system entry.
      Returns:
      true if the file system entry at path is a file; false otherwise.
      Throws:
      FileSystemException
    • isFolder

      boolean isFolder(String path) throws FileSystemException
      Tests whether the file system entry denoted by this path exists and is a folder.
      Parameters:
      path - the path of a file system entry.
      Returns:
      true if the file system entry at path is a folder; false otherwise.
      Throws:
      FileSystemException
    • hasChildren

      boolean hasChildren(String path) throws FileSystemException
      Tests whether the file system entry denoted by this path has child entries.
      Parameters:
      path - the path of a file system entry.
      Returns:
      true if the file system entry at path has child entries; false otherwise.
      Throws:
      FileSystemException
    • length

      long length(String filePath) throws FileSystemException
      Returns the length of the file denoted by this path.
      Parameters:
      filePath - the path of the file.
      Returns:
      The length, in bytes, of the file denoted by this path, or -1L if the length can't be determined.
      Throws:
      FileSystemException - if the path does not denote an existing file.
    • lastModified

      long lastModified(String path) throws FileSystemException
      Returns the time that the file system entry denoted by this path was last modified.
      Parameters:
      path - the path of a file system entry.
      Returns:
      A long value representing the time the file system entry was last modified, measured in milliseconds since the epoch (00:00:00 GMT, January 1, 1970), or 0L if the modification time can't be determined.
      Throws:
      FileSystemException - if the file system entry does not exist.
    • list

      String[] list(String folderPath) throws FileSystemException
      Returns an array of strings naming the files and folders in the folder denoted by this path.
      Parameters:
      folderPath - the path of the folder whose contents is to be listed.
      Returns:
      an array of strings naming the files and folders in the folder denoted by this path.
      Throws:
      FileSystemException - if this path does not denote a folder or if another error occurs.
    • listFiles

      String[] listFiles(String folderPath) throws FileSystemException
      Returns an array of strings naming the files in the folder denoted by this path.
      Parameters:
      folderPath - the path of the folder whose contents is to be listed.
      Returns:
      an array of strings naming the files in the folder denoted by this path.
      Throws:
      FileSystemException - if this path does not denote a folder or if another error occurs.
    • listFolders

      String[] listFolders(String folderPath) throws FileSystemException
      Returns an array of strings naming the folders in the folder denoted by this path.
      Parameters:
      folderPath - the path of the folder whose contents is to be listed.
      Returns:
      an array of strings naming the folders in the folder denoted by this path.
      Throws:
      FileSystemException - if this path does not denote a folder or if another error occurs.
    • deleteFile

      void deleteFile(String filePath) throws FileSystemException
      Deletes the file denoted by this path.
      Parameters:
      filePath - the path of the file to be deleted.
      Throws:
      FileSystemException - if this path does not denote a file or if another error occurs.
    • deleteFolder

      void deleteFolder(String folderPath) throws FileSystemException
      Deletes the folder denoted by this path. Any contents of this folder (folders and files) will be deleted recursively.
      Parameters:
      folderPath - the path of the folder to be deleted.
      Throws:
      FileSystemException - if this path does not denote a folder or if another error occurs.