Java writes blob to the Oracle database

Package com. test;

Import java. NiO. bytebuffer;
Import java. SQL. connection;
Import java. SQL. drivermanager;
Import java. SQL. preparedstatement;
Import java. SQL. resultset;
Import java. SQL. sqlexception;
Import java. SQL. statement;

Public class writeblob {

Private connection conn = NULL;

Private Final Static string Psql = "insert into testblob (numcontentid, blobcontent )"
+ "Values (?, Empty_blob ())";

Private Final Static string ssql = "select blobcontent from testblob where numcontentid =? For Update ";

Private Final Static string usql = "Update testblob set blobcontent =? Where numcontentid =? ";

// Public static string SQL _blobid = "select testblob_seq.nextval from dual ";

Public writeblob () throws exception {
Connection conn = NULL;
Try {
Conn = getconnection ();
Conn. setautocommit (false );

Bytebuffer BB = bytebuffer. Allocate (10836 );
BB. Position (0 );
BB. putint (1 );

// The contentid that calls the insertblob method should use the sequence. In this case, it is simply written to death.

// The following insert method should be the method you want. In the database, 0000 0001 0000 0000 0000 will be displayed ....
// But it does not seem that you actually use bytebuffer
Byte [] b1 = BB. Array ();
Insertblob (Conn, 1, B1 );

// The following figure shows 0000 0001 after the bytebuffer is inserted into the database.
// You do not know what you want.
BB. Flip ();
Byte [] b2 = new byte [BB. Remaining ()];
BB. Get (B2 );
Insertblob (Conn, 2, B2 );

} Catch (exception ex ){
Ex. printstacktrace ();
Conn. rollback ();
} Finally {
If (Conn! = NULL)
Conn. Close ();
}
}

Public void insertblob (connection Conn, int contentid, byte [] content)
Throws exception {
Preparedstatement pstmt = NULL;
Preparedstatement pstmt2 = NULL;
Int id = contentid;
Try {

Pstmt = conn. preparestatement (Psql );
Pstmt2 = conn. preparestatement (usql );

Pstmt. setint (1, ID );
Try {
Pstmt.exe cuteupdate (); // insert an empty object into the database
} Catch (sqlexception ex ){
Ex. printstacktrace ();
}
Pstmt = conn. preparestatement (ssql );
Pstmt. setint (1, ID );
Resultset rs = pstmt.exe cutequery (); // query newly inserted records

Oracle. SQL. Blob Pc = NULL;
While (Rs. Next ()){
PC = (Oracle. SQL. Blob) Rs. getblob (1 );
}
Byte [] DATA = content;
PC. putbytes (1, data );

Pstmt2.setblob (1, PC );
Pstmt2.setint (2, ID );
Pstmt2.executeupdate ();

} Finally {
Try {
Pstmt. Close ();
Pstmt2.close ();
} Catch (exception ee ){
}
}
Return;
}

Public static connection getconnection () throws exception {
Connection conn = NULL;
Statement stmttemp = NULL;
Class. forname ("oracle. JDBC. Driver. oracledriver ");
Conn = drivermanager. getconnection (
"JDBC: oracle: thin: @ 192.168.1.26: 1521: orcl", "Hangzhou L", "123456 ");
Stmttemp = conn. createstatement ();
Return conn;
}

Public static void main (string [] ARGs ){
Try {
Writeblob WB = new writeblob ();
} Catch (exception ex ){
Ex. printstacktrace ();
}
}
}