Interacting with Networks and Databases - Beginning Java 7 - page 887

}

}

}

}
catch (SQLException sqlex)
{

while (sqlex != null)
{

System.err.println("sql error :

"+sqlex.getMessage());
System.err.println("sql

state :

"+sqlex.getSQLState());
System.err.println("error

code:

"+sqlex.getErrorCode());
System.err.println("cause: "+sqlex.getCause());
sqlex = sqlex.getNextException();

}

}

}

Thismethodmostimportantlydemonstrateshowtoserializean ImageIcon object
to a java.sql.Blob object, and then store the Blob object in a table column of
BLOB type.
Youfirstinvoke Connection 's Blob createBlob() methodtocreateanobject
that implements the Blob interface. Because the returned object initially contains no
data,youneedtocall Blob 's OutputStream setBinaryStream(long pos)
method( pos ispassedthe1-basedstartingpositionwithintheblobwherewritingbe-
gins) or one of its overloaded setBytes() methods.
Ifyouchoose setBinaryStream() ,youwouldthenuseobjectserialization(see
Chapter 8 ) to serialize the object to the blob. Don't forget to close the object output
streamwhenyou'refinished—thetry-with-resourcesstatementnicelyhandlesthistask
for you.
After the Blob object has been created and populated, call one of Pre-
paredStatement 's setBlob() methods (e.g., void setBlob(int para-
meterIndex, Blob x) )topasstheblobtothepreparedstatementbeforeitsexe-
cution. Following this execution, the blob must be freed and its resources released.
Consider the following loadDB() source code: