blobfromlocator.java

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            if (blobRs.next()) {
                return ((com.mysql.jdbc.ResultSet) blobRs).getBytes(1, true);
            }

            throw new SQLException("BLOB data not found! Did primary keys change?",
                SQLError.SQL_STATE_GENERAL_ERROR);
        } finally {
            if (blobRs != null) {
                try {
                    blobRs.close();
                } catch (SQLException sqlEx) {
                    ; // do nothing
                }

                blobRs = null;
            }

            if (pStmt != null) {
                try {
                    pStmt.close();
                } catch (SQLException sqlEx) {
                    ; // do nothing
                }

                pStmt = null;
            }
        }
    }

    /**
     * Returns the number of bytes in the BLOB value designated by this Blob
     * object.
     *
     * @return the length of this blob
     *
     * @throws SQLException if a database error occurs
     */
    public long length() throws SQLException {
        java.sql.ResultSet blobRs = null;
        java.sql.PreparedStatement pStmt = null;

        // FIXME: Needs to use identifiers for column/table names
        StringBuffer query = new StringBuffer("SELECT LENGTH(");
        query.append(this.blobColumnName);
        query.append(") FROM ");
        query.append(this.tableName);
        query.append(" WHERE ");

        query.append((String) this.primaryKeyColumns.get(0));
        query.append(" = ?");

        for (int i = 1; i < this.numPrimaryKeys; i++) {
            query.append(" AND ");
            query.append((String) this.primaryKeyColumns.get(i));
            query.append(" = ?");
        }

        try {
            // FIXME: Have this passed in instead
            pStmt = this.creatorResultSet.connection.prepareStatement(query.toString());

            for (int i = 0; i < this.numPrimaryKeys; i++) {
                pStmt.setString(i + 1, (String) this.primaryKeyValues.get(i));
            }

            blobRs = pStmt.executeQuery();

            if (blobRs.next()) {
                return blobRs.getLong(1);
            }

            throw new SQLException("BLOB data not found! Did primary keys change?",
                SQLError.SQL_STATE_GENERAL_ERROR);
        } finally {
            if (blobRs != null) {
                try {
                    blobRs.close();
                } catch (SQLException sqlEx) {
                    ; // do nothing
                }

                blobRs = null;
            }

            if (pStmt != null) {
                try {
                    pStmt.close();
                } catch (SQLException sqlEx) {
                    ; // do nothing
                }

                pStmt = null;
            }
        }
    }

    /**
     * Finds the position of the given pattern in this BLOB.
     *
     * @param pattern the pattern to find
     * @param start where to start finding the pattern
     *
     * @return the position where the pattern is found in the BLOB, -1 if not
     *         found
     *
     * @throws SQLException if a database error occurs
     */
    public long position(java.sql.Blob pattern, long start)
        throws SQLException {
        return position(pattern.getBytes(0, (int) pattern.length()), start);
    }

    /**
     * @see java.sql.Blob#position(byte[], long)
     */
    public long position(byte[] pattern, long start) throws SQLException {
        java.sql.ResultSet blobRs = null;
        java.sql.PreparedStatement pStmt = null;

        // FIXME: Needs to use identifiers for column/table names
        StringBuffer query = new StringBuffer("SELECT LOCATE(");
        query.append("?, ");
        query.append(this.blobColumnName);
        query.append(", ");
        query.append(start);
        query.append(") FROM ");
        query.append(this.tableName);
        query.append(" WHERE ");

        query.append((String) this.primaryKeyColumns.get(0));
        query.append(" = ?");

        for (int i = 1; i < this.numPrimaryKeys; i++) {
            query.append(" AND ");
            query.append((String) this.primaryKeyColumns.get(i));
            query.append(" = ?");
        }

        try {
            // FIXME: Have this passed in instead
            pStmt = this.creatorResultSet.connection.prepareStatement(query.toString());
            pStmt.setBytes(1, pattern);

            for (int i = 0; i < this.numPrimaryKeys; i++) {
                pStmt.setString(i + 2, (String) this.primaryKeyValues.get(i));
            }

            blobRs = pStmt.executeQuery();

            if (blobRs.next()) {
                return blobRs.getLong(1);
            }

            throw new SQLException("BLOB data not found! Did primary keys change?",
                SQLError.SQL_STATE_GENERAL_ERROR);
        } finally {
            if (blobRs != null) {
                try {
                    blobRs.close();
                } catch (SQLException sqlEx) {
                    ; // do nothing
                }

                blobRs = null;
            }

            if (pStmt != null) {
                try {
                    pStmt.close();
                } catch (SQLException sqlEx) {
                    ; // do nothing
                }

                pStmt = null;
            }
        }
    }

    /**
     * @see Blob#truncate(long)
     */
    public void truncate(long length) throws SQLException {
        java.sql.PreparedStatement pStmt = null;

        // FIXME: Needs to use identifiers for column/table names
        StringBuffer query = new StringBuffer("UPDATE ");
        query.append(this.tableName);
        query.append(" SET ");
        query.append(this.blobColumnName);
        query.append(" = LEFT(");
        query.append(this.blobColumnName);
        query.append(", ");
        query.append(length);
        query.append(") WHERE ");

        query.append((String) this.primaryKeyColumns.get(0));
        query.append(" = ?");

        for (int i = 1; i < this.numPrimaryKeys; i++) {
            query.append(" AND ");
            query.append((String) this.primaryKeyColumns.get(i));
            query.append(" = ?");
        }

        try {
            // FIXME: Have this passed in instead
            pStmt = this.creatorResultSet.connection.prepareStatement(query.toString());

            for (int i = 0; i < this.numPrimaryKeys; i++) {
                pStmt.setString(i + 1, (String) this.primaryKeyValues.get(i));
            }

            int rowsUpdated = pStmt.executeUpdate();

            if (rowsUpdated != 1) {
                throw new SQLException("BLOB data not found! Did primary keys change?",
                    SQLError.SQL_STATE_GENERAL_ERROR);
            }
        } finally {
            if (pStmt != null) {
                try {
                    pStmt.close();
                } catch (SQLException sqlEx) {
                    ; // do nothing
                }

                pStmt = null;
            }
        }
    }
}