Class RandomAccessFile

java.lang.Object
org.apache.pdfbox.io.RandomAccessFile
All Implemented Interfaces:
Closeable, AutoCloseable, RandomAccess, RandomAccessRead, RandomAccessWrite

public class RandomAccessFile extends Object implements RandomAccess
A RandomAccess implementation which allows data to be stored in a scratch file on the disk to reduce memory consumption.
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private boolean
     
    private final RandomAccessFile
     
  • Constructor Summary

    Constructors
    Constructor
    Description
    Constructor.
  • Method Summary

    Modifier and Type
    Method
    Description
    int
    Returns an estimate of the number of bytes that can be read.
    private void
    Ensure that the RandomAccessFile is not closed
    void
    Clears all data of the buffer.
    void
     
    long
    Returns offset of next byte to be returned by a read method.
    boolean
    Returns true if this stream has been closed.
    boolean
    A simple test to see if we are at the end of the data.
    long
    The total number of bytes that are available.
    int
    This will peek at the next byte.
    int
    Read a single byte of data.
    int
    read(byte[] b)
    Read a buffer of data.
    int
    read(byte[] b, int offset, int length)
    Read a buffer of data.
    byte[]
    readFully(int length)
    Reads a given number of bytes.
    void
    rewind(int bytes)
    Seek backwards the given number of bytes.
    void
    seek(long position)
    Seek to a position in the data.
    void
    write(byte[] b)
    Write a buffer of data to the stream.
    void
    write(byte[] b, int offset, int length)
    Write a buffer of data to the stream.
    void
    write(int b)
    Write a byte to the stream.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Field Details

  • Constructor Details

  • Method Details

    • close

      public void close() throws IOException
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Throws:
      IOException
    • clear

      public void clear() throws IOException
      Description copied from interface: RandomAccessWrite
      Clears all data of the buffer.
      Specified by:
      clear in interface RandomAccessWrite
      Throws:
      IOException
    • seek

      public void seek(long position) throws IOException
      Description copied from interface: RandomAccessRead
      Seek to a position in the data.
      Specified by:
      seek in interface RandomAccessRead
      Parameters:
      position - The position to seek to.
      Throws:
      IOException - If there is an error while seeking.
    • getPosition

      public long getPosition() throws IOException
      Description copied from interface: RandomAccessRead
      Returns offset of next byte to be returned by a read method.
      Specified by:
      getPosition in interface RandomAccessRead
      Returns:
      offset of next byte which will be returned with next RandomAccessRead.read() (if no more bytes are left it returns a value >= length of source)
      Throws:
      IOException
    • read

      public int read() throws IOException
      Description copied from interface: RandomAccessRead
      Read a single byte of data.
      Specified by:
      read in interface RandomAccessRead
      Returns:
      The byte of data that is being read.
      Throws:
      IOException - If there is an error while reading the data.
    • read

      public int read(byte[] b) throws IOException
      Description copied from interface: RandomAccessRead
      Read a buffer of data.
      Specified by:
      read in interface RandomAccessRead
      Parameters:
      b - The buffer to write the data to.
      Returns:
      The number of bytes that were actually read.
      Throws:
      IOException - If there was an error while reading the data.
    • read

      public int read(byte[] b, int offset, int length) throws IOException
      Description copied from interface: RandomAccessRead
      Read a buffer of data.
      Specified by:
      read in interface RandomAccessRead
      Parameters:
      b - The buffer to write the data to.
      offset - Offset into the buffer to start writing.
      length - The amount of data to attempt to read.
      Returns:
      The number of bytes that were actually read.
      Throws:
      IOException - If there was an error while reading the data.
    • length

      public long length() throws IOException
      Description copied from interface: RandomAccessRead
      The total number of bytes that are available.
      Specified by:
      length in interface RandomAccessRead
      Returns:
      The number of bytes available.
      Throws:
      IOException - If there is an IO error while determining the length of the data stream.
    • checkClosed

      private void checkClosed() throws IOException
      Ensure that the RandomAccessFile is not closed
      Throws:
      IOException
    • isClosed

      public boolean isClosed()
      Description copied from interface: RandomAccessRead
      Returns true if this stream has been closed.
      Specified by:
      isClosed in interface RandomAccessRead
    • write

      public void write(byte[] b, int offset, int length) throws IOException
      Description copied from interface: RandomAccessWrite
      Write a buffer of data to the stream.
      Specified by:
      write in interface RandomAccessWrite
      Parameters:
      b - The buffer to get the data from.
      offset - An offset into the buffer to get the data from.
      length - The length of data to write.
      Throws:
      IOException - If there is an error while writing the data.
    • write

      public void write(byte[] b) throws IOException
      Description copied from interface: RandomAccessWrite
      Write a buffer of data to the stream.
      Specified by:
      write in interface RandomAccessWrite
      Parameters:
      b - The buffer to get the data from.
      Throws:
      IOException - If there is an error while writing the data.
    • write

      public void write(int b) throws IOException
      Description copied from interface: RandomAccessWrite
      Write a byte to the stream.
      Specified by:
      write in interface RandomAccessWrite
      Parameters:
      b - The byte to write.
      Throws:
      IOException - If there is an IO error while writing.
    • peek

      public int peek() throws IOException
      Description copied from interface: RandomAccessRead
      This will peek at the next byte.
      Specified by:
      peek in interface RandomAccessRead
      Returns:
      The next byte on the stream, leaving it as available to read.
      Throws:
      IOException - If there is an error reading the next byte.
    • rewind

      public void rewind(int bytes) throws IOException
      Description copied from interface: RandomAccessRead
      Seek backwards the given number of bytes.
      Specified by:
      rewind in interface RandomAccessRead
      Parameters:
      bytes - the number of bytes to be seeked backwards
      Throws:
      IOException - If there is an error while seeking
    • readFully

      public byte[] readFully(int length) throws IOException
      Description copied from interface: RandomAccessRead
      Reads a given number of bytes.
      Specified by:
      readFully in interface RandomAccessRead
      Parameters:
      length - the number of bytes to be read
      Returns:
      a byte array containing the bytes just read
      Throws:
      IOException - if an I/O error occurs while reading data
    • isEOF

      public boolean isEOF() throws IOException
      Description copied from interface: RandomAccessRead
      A simple test to see if we are at the end of the data.
      Specified by:
      isEOF in interface RandomAccessRead
      Returns:
      true if we are at the end of the data.
      Throws:
      IOException - If there is an error reading the next byte.
    • available

      public int available() throws IOException
      Description copied from interface: RandomAccessRead
      Returns an estimate of the number of bytes that can be read.
      Specified by:
      available in interface RandomAccessRead
      Returns:
      the number of bytes that can be read
      Throws:
      IOException - if this random access has been closed