Package org.postgresql.largeobject

Class BlobInputStream

java.lang.Object
java.io.InputStream
org.postgresql.largeobject.BlobInputStream
All Implemented Interfaces:
Closeable, AutoCloseable
public class BlobInputStream extends InputStream
This is an implementation of an InputStream from a large object.

  • Constructor Details

    • BlobInputStream

      public BlobInputStream(LargeObject lo)
      Parameters:
      lo - LargeObject to read from

    • BlobInputStream

      public BlobInputStream(LargeObject lo, int bsize)
      Parameters:
      lo - LargeObject to read from
      bsize - buffer size

    • BlobInputStream

      public BlobInputStream(LargeObject lo, int bsize, long limit)
      Parameters:
      lo - LargeObject to read from
      bsize - buffer size
      limit - max number of bytes to read

  • Method Details

    • read

      public int read() throws IOException
      The minimum required to implement input stream.
      Specified by:
      read in class InputStream
      Throws:
      IOException

    • read

      public int read(byte[] dest, int off, int len) throws IOException
      Overrides:
      read in class InputStream
      Throws:
      IOException

    • close

      public void close() throws IOException
      Closes this input stream and releases any system resources associated with the stream.

      The close method of InputStream does nothing.

      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Overrides:
      close in class InputStream
      Throws:
      IOException - if an I/O error occurs.

    • mark

      public void mark(int readlimit)
      Marks the current position in this input stream. A subsequent call to the reset method repositions this stream at the last marked position so that subsequent reads re-read the same bytes.

      The readlimit arguments tells this input stream to allow that many bytes to be read before the mark position gets invalidated.

      The general contract of mark is that, if the method markSupported returns true, the stream somehow remembers all the bytes read after the call to mark and stands ready to supply those same bytes again if and whenever the method reset is called. However, the stream is not required to remember any data at all if more than readlimit bytes are read from the stream before reset is called.

      Marking a closed stream should not have any effect on the stream.

      Overrides:
      mark in class InputStream
      Parameters:
      readlimit - the maximum limit of bytes that can be read before the mark position becomes invalid.
      See Also:

    • reset

      public void reset() throws IOException
      Repositions this stream to the position at the time the mark method was last called on this input stream. NB: If mark is not called we move to the beginning.
      Overrides:
      reset in class InputStream
      Throws:
      IOException
      See Also:

    • markSupported

      public boolean markSupported()
      Tests if this input stream supports the mark and reset methods. The markSupported method of InputStream returns false.
      Overrides:
      markSupported in class InputStream
      Returns:
      true if this true type supports the mark and reset method; false otherwise.
      See Also:

    • skip

      public long skip(long n) throws IOException
      Skips over and discards n bytes of data from this input stream.

      Unlike the default implementation, this seeks instead of reading and discarding the bytes, so the cost does not grow with n.

      Large objects are sparse, so the stream allows skipping past the current end of the object. Subsequent reads then return -1, and the skipped count still reflects the requested distance, as the InputStream.skip(long) contract permits.

      Overrides:
      skip in class InputStream
      Parameters:
      n - the number of bytes to be skipped
      Returns:
      the actual number of bytes skipped, which may be zero
      Throws:
      IOException - if the underlying seek fails, in particular when the target position exceeds the maximum large object size the server accepts
      See Also: