Package com.adobe.internal.io

Class RandomAccessFileByteReader

  • All Implemented Interfaces:
    ByteReader
    public class RandomAccessFileByteReader
extends java.lang.Object
    An implementation of the ByteReader interface that provides access to a RandomAccessFile. This implementation uses buffering to limit the number of calls to the methods of the RandomAccessFile class. This is because such methods use JNI and any calls to native code from Java are very slow. This class is not threadsafe. It is not safe to pass an instance of this class to multiple threads. It is not safe to pass an instance of this class to multiple users even if in the same thread. It is not safe to give the same RandomAccessFile to multiple instances of this class.

    • Field Summary

      • Fields inherited from interface com.adobe.internal.io.ByteReader

        EOF

    • Constructor Summary

      Constructors 
      Constructor Description
      RandomAccessFileByteReader​(java.io.RandomAccessFile file)
      Constructor.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void close()
      Closes this ByteReader and releases any system resources associated with this stream.
      long length()
      Returns the number of total bytes in the repository that are visible through this API.
      int read​(long position)
      Read a single byte from the underlying bytes at the given position.
      int read​(long position, byte[] b, int offset, int length)
      Transfers bytes from the underlying repository into the given destination array.

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • RandomAccessFileByteReader

        public RandomAccessFileByteReader​(java.io.RandomAccessFile file)
        Constructor.
        Parameters:
        file - the file to wrap.

    • Method Detail

      • read

        public int read​(long position)
         throws java.io.IOException
        Description copied from interface: ByteReader
        Read a single byte from the underlying bytes at the given position.
        Specified by:
        read in interface ByteReader
        Parameters:
        position - the position to read the byte from.
        Returns:
        the byte at the postion or EOF if the position is outside of the legal range.
        Throws:
        java.io.IOException - if an error occurs during the read operation
        See Also:
        ByteReader.read(long)

      • read

        public int read​(long position,
                byte[] b,
                int offset,
                int length)
         throws java.io.IOException
        Description copied from interface: ByteReader
        Transfers bytes from the underlying repository into the given destination array. Copy up to length bytes from the repository starting at the postion given into the given array starting at the given offset.
        Specified by:
        read in interface ByteReader
        Parameters:
        position - the position to read the byte from.
        b - the array to write the bytes into.
        offset - the offset in the array at which the first byte is written.
        length - the maximum number of bytes to write into the array.
        Returns:
        the number of bytes actually written to the array.
        Throws:
        java.io.IOException - if an error occurs during the read operation
        See Also:
        ByteReader.read(long, byte[], int, int)

      • length

        public long length()
            throws java.io.IOException
        Description copied from interface: ByteReader
        Returns the number of total bytes in the repository that are visible through this API.
        Specified by:
        length in interface ByteReader
        Returns:
        the number of bytes in the repository.
        Throws:
        java.io.IOException - if an error occurs while trying to determine the length
        See Also:
        ByteReader.length()

      • close

        public void close()
           throws java.io.IOException
        Description copied from interface: ByteReader
        Closes this ByteReader and releases any system resources associated with this stream.
        Specified by:
        close in interface ByteReader
        Throws:
        java.io.IOException - if an error occurs while trying to close
        See Also:
        ByteReader.close()