Package nl.cwi.monetdb.jdbc

Class MonetBlob

java.lang.Object
nl.cwi.monetdb.jdbc.MonetBlob
All Implemented Interfaces:
Serializable, Comparable<MonetBlob>, Blob
public final class MonetBlob
extends Object
implements Blob, Serializable, Comparable<MonetBlob>
The MonetBlob class implements the Blob interface. Because MonetDB/SQL currently has no support for streams, this class is a shallow wrapper of a byte[]. It is more or less supplied to enable an application that depends on it to run. It may be obvious that it is a real resource expensive workaround that contradicts the benefits for a Blob: avoidance of huge resource consumption. Use of this class is highly discouraged.
Author:
Fabian Groffen
See Also:
Serialized Form

  • Constructor Summary

    Constructors 
    Constructor Description
    MonetBlob​(byte[] buf)  

  • Method Summary

    Modifier and Type Method Description
    int compareTo​(MonetBlob o)  
    boolean equals​(Object obj)
    Overriding the equals method for the byte array.
    void free()
    This method frees the Blob object and releases the resources that it holds.
    InputStream getBinaryStream()
    Retrieves the BLOB value designated by this Blob instance as a stream.
    InputStream getBinaryStream​(long pos, long length)
    Returns an InputStream object that contains a partial Blob value, starting with the byte specified by pos, which is length bytes in length.
    byte[] getBuffer()  
    byte[] getBytes​(long pos, int length)
    Retrieves all or part of the BLOB value that this Blob object represents, as an array of bytes.
    int hashCode()
    Overriding the hashCode method for the byte array.
    long length()
    Returns the number of bytes in the BLOB value designated by this Blob object.
    long position​(byte[] pattern, long start)
    Retrieves the byte position at which the specified byte array pattern begins within the BLOB value that this Blob object represents.
    long position​(Blob pattern, long start)
    Retrieves the byte position in the BLOB value designated by this Blob object at which pattern begins.
    OutputStream setBinaryStream​(long pos)
    Retrieves a stream that can be used to write to the BLOB value that this Blob object represents.
    int setBytes​(long pos, byte[] bytes)
    Writes the given array of bytes to the BLOB value that this Blob object represents, starting at position pos, and returns the number of bytes written.
    int setBytes​(long pos, byte[] bytes, int offset, int len)
    Writes all or part of the given byte array to the BLOB value that this Blob object represents and returns the number of bytes written.
    String toString()
    Overriding the toString method for the byte array.
    void truncate​(long len)
    Truncates the BLOB value that this Blob object represents to be len bytes in length.

    Methods inherited from class java.lang.Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait

  • Constructor Details

    • MonetBlob

      public MonetBlob​(byte[] buf)

  • Method Details

    • getBuffer

      public byte[] getBuffer()

    • 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. After free has been called, any attempt to invoke a method other than free will result in a SQLException being thrown. 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() throws SQLException
      Retrieves the BLOB value designated by this Blob instance as a stream.
      Specified by:
      getBinaryStream in interface Blob
      Returns:
      a stream containing the BLOB data
      Throws:
      SQLException - if there is an error accessing the BLOB value

    • 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 the number of bytes in the Blob

    • getBytes

      public byte[] getBytes​(long pos, int length) throws SQLException
      Retrieves all or part of the BLOB value that this Blob object represents, as an array of bytes. This byte array contains up to length consecutive bytes starting at position pos.
      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 - 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 pos.
      Throws:
      SQLException - if there is an error accessing the BLOB value

    • length

      public long length() throws SQLException
      Returns the number of bytes in the BLOB value designated by this Blob object.
      Specified by:
      length in interface Blob
      Returns:
      length of the BLOB in bytes
      Throws:
      SQLException - if there is an error accessing the length of the BLOB value

    • position

      public long position​(Blob pattern, long start) throws SQLException
      Retrieves the byte position in the BLOB value designated by this Blob object at which pattern begins. The search begins at position start.
      Specified by:
      position in interface Blob
      Parameters:
      pattern - the Blob object designating the BLOB value for which to search
      start - the position in the BLOB value at which to begin searching; the first position is 1
      Returns:
      the position at which the pattern begins, else -1
      Throws:
      SQLException - if there is an error accessing the BLOB value

    • position

      public long position​(byte[] pattern, long start) throws SQLException
      Retrieves the byte position at which the specified byte array pattern begins within the BLOB value that this Blob object represents. The search for pattern begins at position start.
      Specified by:
      position in interface Blob
      Parameters:
      pattern - the byte array for which to search
      start - the position at which to begin searching; the first position is 1
      Returns:
      the position at which the pattern appears, else -1
      Throws:
      SQLException - if there is an error accessing the BLOB value

    • setBinaryStream

      public OutputStream setBinaryStream​(long pos) throws SQLException
      Retrieves a stream that can be used to write to the BLOB value that this Blob object represents. The stream begins at position pos. The bytes written to the stream will overwrite the existing bytes in the Blob object starting at the position pos. If the end of the Blob value is reached while writing to the stream, then the length of the Blob value will be increased to accomodate the extra bytes.
      Specified by:
      setBinaryStream in interface Blob
      Parameters:
      pos - the position in the BLOB value at which to start writing; the first position is 1
      Returns:
      a java.io.OutputStream object to which data can be written
      Throws:
      SQLException - if there is an error accessing the BLOB value or if pos is less than 1
      SQLFeatureNotSupportedException - if the JDBC driver does not support this method

    • setBytes

      public int setBytes​(long pos, byte[] bytes) throws SQLException
      Writes the given array of bytes to the BLOB value that this Blob object represents, starting at position pos, and returns the number of bytes written.
      Specified by:
      setBytes in interface Blob
      Parameters:
      pos - the position in the BLOB object at which to start writing
      bytes - the array of bytes to be written to the BLOB value that this Blob object represents
      Returns:
      the number of bytes written
      Throws:
      SQLException - if there is an error accessing the BLOB value or if pos is less than 1

    • setBytes

      public int setBytes​(long pos, byte[] bytes, int offset, int len) throws SQLException
      Writes all or part of the given byte array to the BLOB value that this Blob object represents and returns the number of bytes written. Writing starts at position pos in the BLOB value; len bytes from the given byte array are written.
      Specified by:
      setBytes in interface Blob
      Parameters:
      pos - the position in the BLOB object at which to start writing
      bytes - the array of bytes to be written to this BLOB object
      offset - the offset into the array bytes at which to start reading the bytes to be set
      len - the number of bytes to be written to the BLOB value from the array of bytes bytes
      Returns:
      the number of bytes written
      Throws:
      SQLException - if there is an error accessing the BLOB value or if pos is less than 1

    • truncate

      public void truncate​(long len) throws SQLException
      Truncates the BLOB value that this Blob object represents to be len bytes in length.
      Specified by:
      truncate in interface Blob
      Parameters:
      len - the length, in bytes, to which the BLOB value should be truncated
      Throws:
      SQLException - if there is an error accessing the BLOB value

    • equals

      public boolean equals​(Object obj)
      Overriding the equals method for the byte array.
      Overrides:
      equals in class Object

    • hashCode

      public int hashCode()
      Overriding the hashCode method for the byte array.
      Overrides:
      hashCode in class Object

    • toString

      public String toString()
      Overriding the toString method for the byte array.
      Overrides:
      toString in class Object

    • compareTo

      public int compareTo​(MonetBlob o)
      Specified by:
      compareTo in interface Comparable<MonetBlob>