Class InputStreamFile<F extends BaseStorageFactory>

java.lang.Object
org.apache.derby.impl.io.InputStreamFile<F>
Type Parameters:
F - the storage factory class used by the subsubprotocol
All Implemented Interfaces:
StorageFile
Direct Known Subclasses:
CPFile, JarDBFile, URLFile
abstract class InputStreamFile<F extends BaseStorageFactory> extends Object implements StorageFile
This class provides the base for read-only stream implementations of the StorageFile interface. It is used with the classpath, jar, http, and https subsubprotocols

  • Field Details

    • path

      final String path

    • nameStart

      final int nameStart

    • storageFactory

      final F extends BaseStorageFactory storageFactory

  • Constructor Details

    • InputStreamFile

      InputStreamFile(F storageFactory, String path)

    • InputStreamFile

      InputStreamFile(F storageFactory, String parent, String name)

    • InputStreamFile

      InputStreamFile(InputStreamFile<F> dir, String name)

    • InputStreamFile

      InputStreamFile(F storageFactory, String child, int pathLen)

  • Method Details

    • equals

      public boolean equals(Object other)
      Overrides:
      equals in class Object

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object

    • list

      public String[] list()
      Get the names of all files and sub-directories in the directory named by this path name.
      Specified by:
      list in interface StorageFile
      Returns:
      An array of the names of the files and directories in this directory denoted by this abstract pathname. The returned array will have length 0 if this directory is empty. Returns null if this StorageFile is not a directory, or if an I/O error occurs.

    • canWrite

      public boolean canWrite()
      Determine whether the named file is writable.
      Specified by:
      canWrite in interface StorageFile
      Returns:
      true if the file exists and is writable, false if not.

    • exists

      public abstract boolean exists()
      Tests whether the named file exists.
      Specified by:
      exists in interface StorageFile
      Returns:
      true if the named file exists, false if not.

    • isDirectory

      public boolean isDirectory()
      Tests whether the named file is a directory, or not. This is only called in writable storage factories.
      Specified by:
      isDirectory in interface StorageFile
      Returns:
      true if named file exists and is a directory, false if not. The return value is undefined if the storage is read-only.

    • delete

      public boolean delete()
      Deletes the named file or empty directory. This method does not delete non-empty directories.
      Specified by:
      delete in interface StorageFile
      Returns:
      true if the named file or directory is successfully deleted, false if not

    • deleteAll

      public boolean deleteAll()
      Deletes the named file and, if it is a directory, all the files and directories it contains.
      Specified by:
      deleteAll in interface StorageFile
      Returns:
      true if the named file or directory is successfully deleted, false if not

    • getPath

      public String getPath()
      Converts this StorageFile into a pathname string. The character returned by StorageFactory.getSeparator() is used to separate the directory and file names in the sequence.

      The returned path may include the database directory. Therefore it cannot be directly used to make an StorageFile equivalent to this one.

      Specified by:
      getPath in interface StorageFile
      Returns:
      The pathname as a string.
      See Also:

    • getCanonicalPath

      public String getCanonicalPath() throws IOException
      Description copied from interface: StorageFile
      Converts this StorageFile into a canonical pathname string. The form of the canonical path is system dependent.
      Specified by:
      getCanonicalPath in interface StorageFile
      Returns:
      The pathname as a string.
      Throws:
      IOException - if an I/O error occurred while finding the canonical name

    • getName

      public String getName()
      Specified by:
      getName in interface StorageFile
      Returns:
      The last segment in the path name, "" if the path name sequence is empty.

    • createNewFile

      public boolean createNewFile() throws IOException
      If the named file does not already exist then create it as an empty normal file. The implementation must synchronize with other threads accessing the same file (in the same or a different process). If two threads both attempt to create a file with the same name at the same time then at most one should succeed.
      Specified by:
      createNewFile in interface StorageFile
      Returns:
      true if this thread's invocation of createNewFile successfully created the named file; false if not, i.e. false if the named file already exists or if another concurrent thread created it.
      Throws:
      IOException - - If the directory does not exist or some other I/O error occurred

    • renameTo

      public boolean renameTo(StorageFile newName)
      Rename the file denoted by this name. Note that StorageFile objects are immutable. This method renames the underlying file, it does not change this StorageFile object. The StorageFile object denotes the same name as before, however the exists() method will return false after the renameTo method executes successfully.

      It is not specified whether this method will succeed if a file already exists under the new name.

      Specified by:
      renameTo in interface StorageFile
      Parameters:
      newName - the new name.
      Returns:
      true if the rename succeeded, false if not.

    • mkdir

      public boolean mkdir()
      Creates the named directory.
      Specified by:
      mkdir in interface StorageFile
      Returns:
      true if the directory was created; false if not.

    • mkdirs

      public boolean mkdirs()
      Creates the named directory, and all nonexistent parent directories.
      Specified by:
      mkdirs in interface StorageFile
      Returns:
      true if the directory was created, false if not

    • getParentDir

      public StorageFile getParentDir()
      Get the name of the parent directory if this name includes a parent.
      Specified by:
      getParentDir in interface StorageFile
      Returns:
      An StorageFile denoting the parent directory of this StorageFile, if it has a parent, null if it does not have a parent.

    • getParentDir

      abstract StorageFile getParentDir(int pathLen)
      Get the parent of this file.
      Parameters:
      pathLen - the length of the parent's path name.

    • setReadOnly

      public boolean setReadOnly()
      Make the named file or directory read-only. This interface does not specify whether this also makes the file undeletable.
      Specified by:
      setReadOnly in interface StorageFile
      Returns:
      true if the named file or directory was made read-only, or it already was read-only; false if not.

    • getOutputStream

      public OutputStream getOutputStream() throws FileNotFoundException
      Creates an output stream from a file name. If a normal file already exists with this name it will first be truncated to zero length.
      Specified by:
      getOutputStream in interface StorageFile
      Returns:
      an output stream suitable for writing to the file.
      Throws:
      FileNotFoundException - if the file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason.

    • getOutputStream

      public OutputStream getOutputStream(boolean append) throws FileNotFoundException
      Creates an output stream from a file name. If a normal file already exists with this name it will first be truncated to zero length.
      Specified by:
      getOutputStream in interface StorageFile
      Parameters:
      append - If true then data will be appended to the end of the file, if it already exists. If false and a normal file already exists with this name the file will first be truncated to zero length.
      Returns:
      an output stream suitable for writing to the file.
      Throws:
      FileNotFoundException - if the file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason.

    • getInputStream

      public abstract InputStream getInputStream() throws FileNotFoundException
      Creates an input stream from a file name.
      Specified by:
      getInputStream in interface StorageFile
      Returns:
      an input stream suitable for reading from the file.
      Throws:
      FileNotFoundException - if the file is not found.

    • getExclusiveFileLock

      public int getExclusiveFileLock() throws StandardException
      Get an exclusive lock with this name. This is used to ensure that two or more JVMs do not open the same database at the same time.
      Specified by:
      getExclusiveFileLock in interface StorageFile
      Returns:
      EXCLUSIVE_FILE_LOCK_NOT_AVAILABLE if the lock cannot be acquired because it is already held.
      EXCLUSIVE_FILE_LOCK if the lock was successfully acquired.
      NO_FILE_LOCK_SUPPORT if the system does not support exclusive locks.
      Throws:
      StandardException

    • releaseExclusiveFileLock

      public void releaseExclusiveFileLock()
      Release the resource associated with an earlier acquired exclusive lock
      Specified by:
      releaseExclusiveFileLock in interface StorageFile
      See Also:

    • getRandomAccessFile

      public StorageRandomAccessFile getRandomAccessFile(String mode) throws FileNotFoundException
      Get a random access file.
      Specified by:
      getRandomAccessFile in interface StorageFile
      Parameters:
      mode - "r", "rw", "rws", or "rwd". The "rws" and "rwd" modes specify that the data is to be written to persistent store, consistent with the java.io.RandomAccessFile class ("synchronized" with the persistent storage, in the file system meaning of the word "synchronized"). However the implementation is not required to implement the "rws" or "rwd" modes. The implementation may treat "rws" and "rwd" as "rw". It is up to the user of this interface to call the StorageRandomAccessFile.sync method. However, if the "rws" or "rwd" modes are supported and the RandomAccessFile was opened in "rws" or "rwd" mode then the implementation of StorageRandomAccessFile.sync need not do anything.
      Returns:
      an object that can be used for random access to the file.
      Throws:
      IllegalArgumentException - if the mode argument is not equal to one of "r", "rw", "rws", or "rwd".
      FileNotFoundException - if the file exists but is a directory rather than a regular file, or cannot be opened or created for any other reason .
      See Also:

    • toString

      public String toString()
      Get the file name for diagnostic purposes. Usually the same as getPath().
      Overrides:
      toString in class Object
      Returns:
      the file name

    • limitAccessToOwner

      public void limitAccessToOwner()
      Description copied from interface: StorageFile
      Use when creating a new file. By default, a file created in an underlying file system, if applicable, will have read and write access for the file owner unless the property derby.useDefaultFilePermissions is set to true.
      Specified by:
      limitAccessToOwner in interface StorageFile