Class ClientBlob

  • All Implemented Interfaces:
    java.sql.Blob, UnitOfWorkListener

    public class ClientBlob
    extends Lob
    implements java.sql.Blob
    • Field Detail

      • binaryString_

        byte[] binaryString_
      • binaryStream_

        java.io.InputStream binaryStream_
      • dataOffset_

        int dataOffset_
    • Constructor Detail

      • ClientBlob

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

        ClientBlob​(Agent agent,
                   java.io.InputStream binaryStream,
                   int length)
      • ClientBlob

        ClientBlob​(Agent agent,
                   java.io.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 Detail

      • length

        public long length()
                    throws java.sql.SQLException
        Specified by:
        length in interface java.sql.Blob
        Specified by:
        length in class Lob
        Throws:
        java.sql.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 java.sql.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 java.sql.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:
        java.sql.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.
      • getBinaryStream

        public java.io.InputStream getBinaryStream()
                                            throws java.sql.SQLException
        Specified by:
        getBinaryStream in interface java.sql.Blob
        Throws:
        java.sql.SQLException
      • position

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

        public long position​(java.sql.Blob pattern,
                             long start)
                      throws java.sql.SQLException
        Specified by:
        position in interface java.sql.Blob
        Throws:
        java.sql.SQLException
      • setBytes

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

        public int setBytes​(long pos,
                            byte[] bytes,
                            int offset,
                            int len)
                     throws java.sql.SQLException
        Specified by:
        setBytes in interface java.sql.Blob
        Throws:
        java.sql.SQLException
      • setBinaryStream

        public java.io.OutputStream setBinaryStream​(long pos)
                                             throws java.sql.SQLException
        Specified by:
        setBinaryStream in interface java.sql.Blob
        Throws:
        java.sql.SQLException
      • truncate

        public void truncate​(long len)
                      throws java.sql.SQLException
        Specified by:
        truncate in interface java.sql.Blob
        Throws:
        java.sql.SQLException
      • free

        public void free()
                  throws java.sql.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 java.sql.Blob
        Throws:
        java.sql.SQLException - if an error occurs releasing the Blob's resources
      • getBinaryStream

        public java.io.InputStream getBinaryStream​(long pos,
                                                   long length)
                                            throws java.sql.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 java.sql.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:
        java.sql.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)