Package com.itextpdf.io.source

Class WindowRandomAccessSource

  • All Implemented Interfaces:
    IRandomAccessSource
    public class WindowRandomAccessSource
extends java.lang.Object
implements IRandomAccessSource
    A RandomAccessSource that wraps another RandomAccessSource and provides a window of it at a specific offset and over a specific length. Position 0 becomes the offset position in the underlying source.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private long length
      The length
      private long offset
      The amount to offset the source by
      private IRandomAccessSource source
      The source

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void close()
      Closes this source.
      int get​(long position)
      Gets a byte at the specified position
      int get​(long position, byte[] bytes, int off, int len)
      Read an array of bytes of specified length from the specified position of source to the buffer applying the offset.
      long length()
      Gets the length of the source

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • offset

        private final long offset
        The amount to offset the source by

      • length

        private final long length
        The length

    • Constructor Detail

      • WindowRandomAccessSource

        public WindowRandomAccessSource​(IRandomAccessSource source,
                                long offset)
        Constructs a new OffsetRandomAccessSource that extends to the end of the underlying source
        Parameters:
        source - the source
        offset - the amount of the offset to use

      • WindowRandomAccessSource

        public WindowRandomAccessSource​(IRandomAccessSource source,
                                long offset,
                                long length)
        Constructs a new OffsetRandomAccessSource with an explicit length
        Parameters:
        source - the source
        offset - the amount of the offset to use
        length - the number of bytes to be included in this RAS

    • Method Detail

      • get

        public int get​(long position)
        throws java.io.IOException
        Gets a byte at the specified position Note that the position will be adjusted to read from the corrected location in the underlying source
        Specified by:
        get in interface IRandomAccessSource
        Parameters:
        position - byte position
        Returns:
        the byte, or -1 if EOF is reached
        Throws:
        java.io.IOException - in case of any reading error.

      • get

        public int get​(long position,
               byte[] bytes,
               int off,
               int len)
        throws java.io.IOException
        Read an array of bytes of specified length from the specified position of source to the buffer applying the offset. If the number of bytes requested cannot be read, all the possible bytes will be read to the buffer, and the number of actually read bytes will be returned. Note that the position will be adjusted to read from the corrected location in the underlying source
        Specified by:
        get in interface IRandomAccessSource
        Parameters:
        position - the position in the RandomAccessSource to read from
        bytes - output buffer
        off - offset into the output buffer where results will be placed
        len - the number of bytes to read
        Returns:
        the number of bytes actually read, or -1 if the file is at EOF
        Throws:
        java.io.IOException - in case of any I/O error.

      • length

        public long length()
        Gets the length of the source Note that the length will be adjusted to read from the corrected location in the underlying source
        Specified by:
        length in interface IRandomAccessSource
        Returns:
        the length of this source

      • close

        public void close()
           throws java.io.IOException
        Closes this source. The underlying data structure or source (if any) will also be closed
        Specified by:
        close in interface IRandomAccessSource
        Throws:
        java.io.IOException - in case of any reading error.