Package org.apache.derby.impl.io

Class InputStreamFile<F extends BaseStorageFactory>

  • 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 java.lang.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 Detail

      • path

        final java.lang.String path

      • nameStart

        final int nameStart

    • Constructor Detail

      • InputStreamFile

        InputStreamFile​(F storageFactory,
                java.lang.String path)

      • InputStreamFile

        InputStreamFile​(F storageFactory,
                java.lang.String parent,
                java.lang.String name)

      • InputStreamFile

        InputStreamFile​(InputStreamFile<F> dir,
                java.lang.String name)

      • InputStreamFile

        InputStreamFile​(F storageFactory,
                java.lang.String child,
                int pathLen)

    • Method Detail

      • equals

        public boolean equals​(java.lang.Object other)
        Overrides:
        equals in class java.lang.Object

      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class java.lang.Object

      • list

        public java.lang.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 java.lang.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:
        StorageFactory.getSeparator()

      • getCanonicalPath

        public java.lang.String getCanonicalPath()
                                  throws java.io.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:
        java.io.IOException - if an I/O error occurred while finding the canonical name

      • getName

        public java.lang.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 java.io.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:
        java.io.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 java.io.OutputStream getOutputStream()
                                     throws java.io.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:
        java.io.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 java.io.OutputStream getOutputStream​(boolean append)
                                     throws java.io.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:
        java.io.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 java.io.InputStream getInputStream()
                                            throws java.io.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:
        java.io.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

      • getRandomAccessFile

        public StorageRandomAccessFile getRandomAccessFile​(java.lang.String mode)
                                            throws java.io.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:
        java.lang.IllegalArgumentException - if the mode argument is not equal to one of "r", "rw", "rws", or "rwd".
        java.io.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:
        java.io.RandomAccessFile

      • toString

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