Class ClientBlob

java.lang.Object
org.apache.derby.client.am.Lob
org.apache.derby.client.am.ClientBlob
All Implemented Interfaces:
Blob, UnitOfWorkListener
public class ClientBlob extends Lob implements Blob

  • Field Details

    • binaryString_

      byte[] binaryString_

    • binaryStream_

      InputStream binaryStream_

    • dataOffset_

      int dataOffset_

  • Constructor Details

    • ClientBlob

      public ClientBlob(byte[] binaryString, Agent agent, int dataOffset)

    • ClientBlob

      ClientBlob(Agent agent, InputStream binaryStream, int length)

    • ClientBlob

      ClientBlob(Agent agent, InputStream binaryStream)
      Create a new Blob from a stream with unknown length. Important: This constructor is a temporary solution for implementing lengthless overloads in the JDBC4 API. Before a proper solution can be implemented, we need to enable streaming without having to know the stream length in the DRDA protocol. See Jira DERBY-1471 and DERBY-1417 for more details. Shortcomings: This constructor will cause the whole stream to be materialized to determine its length. If the stream is big enough, the client will fail with an OutOfMemoryError. Since this is a temporary solution, state checking is not added to all methods as it would clutter up the class severely. After using the constructor, the length-method must be called, which will materialize the stream and determine the length. Do not pass a Blob object created with this constructor to the user!
      Parameters:
      agent -
      binaryStream - the stream to get data from

    • ClientBlob

      public ClientBlob(Agent agent, int locator)
      Create a Blob object for a Blob value stored on the server and indentified by locator.
      Parameters:
      agent - context for this Blob object (incl. connection)
      locator - reference id to Blob value on server

  • Method Details

    • length

      public long length() throws SQLException
      Specified by:
      length in interface Blob
      Specified by:
      length in class Lob
      Throws:
      SQLException

    • getLocatorLength

      long getLocatorLength() throws SqlException
      Get the length in bytes of the Blob value represented by this locator based object. A stored procedure call will be made to get it from the server.
      Overrides:
      getLocatorLength in class Lob
      Returns:
      length of Blob in bytes
      Throws:
      SqlException

    • getBytes

      public byte[] getBytes(long pos, int length) throws SQLException
      Returns as an array of bytes part or all of the BLOB value that this Blob object designates. The byte array contains up to length consecutive bytes starting at position pos. The starting position must be between 1 and the length of the BLOB plus 1. This allows for zero-length BLOB values, from which only zero-length byte arrays can be returned. If a larger length is requested than there are bytes available, characters from the start position to the end of the BLOB are returned.
      Specified by:
      getBytes in interface Blob
      Parameters:
      pos - the ordinal position of the first byte in the BLOB value to be extracted; the first byte is at position 1
      length - is the number of consecutive bytes to be copied
      Returns:
      a byte array containing up to length consecutive bytes from the BLOB value designated by this Blob object, starting with the byte at position startPos.
      Throws:
      SQLException - if there is an error accessing the BLOB NOTE: If the starting position is the length of the BLOB plus 1, zero bytess are returned regardless of the length requested.

    • getBytesX

      private byte[] getBytesX(long pos, int length) throws SqlException
      Throws:
      SqlException

    • getBinaryStream

      public InputStream getBinaryStream() throws SQLException
      Specified by:
      getBinaryStream in interface Blob
      Throws:
      SQLException

    • getBinaryStreamX

      InputStream getBinaryStreamX() throws SqlException
      Throws:
      SqlException

    • position

      public long position(byte[] pattern, long start) throws SQLException
      Specified by:
      position in interface Blob
      Throws:
      SQLException

    • positionX

      private long positionX(byte[] pattern, long start) throws SqlException
      Throws:
      SqlException

    • position

      public long position(Blob pattern, long start) throws SQLException
      Specified by:
      position in interface Blob
      Throws:
      SQLException

    • positionX

      private long positionX(Blob pattern, long start) throws SqlException
      Throws:
      SqlException

    • setBytes

      public int setBytes(long pos, byte[] bytes) throws SQLException
      Specified by:
      setBytes in interface Blob
      Throws:
      SQLException

    • setBytes

      public int setBytes(long pos, byte[] bytes, int offset, int len) throws SQLException
      Specified by:
      setBytes in interface Blob
      Throws:
      SQLException

    • setBytesX

      int setBytesX(long pos, byte[] bytes, int offset, int len) throws SqlException
      Throws:
      SqlException

    • setBinaryStream

      public OutputStream setBinaryStream(long pos) throws SQLException
      Specified by:
      setBinaryStream in interface Blob
      Throws:
      SQLException

    • truncate

      public void truncate(long len) throws SQLException
      Specified by:
      truncate in interface Blob
      Throws:
      SQLException

    • free

      public void free() throws SQLException
      This method frees the Blob object and releases the resources that it holds. The object is invalid once the free method is called. If free is called multiple times, the subsequent calls to free are treated as a no-op.
      Specified by:
      free in interface Blob
      Throws:
      SQLException - if an error occurs releasing the Blob's resources

    • getBinaryStream

      public InputStream getBinaryStream(long pos, long length) throws SQLException
      Returns an InputStream object that contains a partial Blob value, starting with the byte specified by pos, which is length bytes in length.
      Specified by:
      getBinaryStream in interface Blob
      Parameters:
      pos - the offset to the first byte of the partial value to be retrieved. The first byte in the Blob is at position 1.
      length - the length in bytes of the partial value to be retrieved
      Returns:
      InputStream through which the partial Blob value can be read.
      Throws:
      SQLException - if pos is less than 1 or if pos is greater than the number of bytes in the Blob or if pos + length is greater than Blob.length() +1

    • isBinaryString

      public boolean isBinaryString()

    • isBinaryStream

      public boolean isBinaryStream()

    • binaryStringPosition

      private long binaryStringPosition(byte[] pattern, long start)

    • isSubString

      private boolean isSubString(byte[] pattern, int index)

    • materializeStream

      protected void materializeStream() throws SqlException
      Materialize the stream used for input to the database.
      Specified by:
      materializeStream in class Lob
      Throws:
      SqlException