Storing Java objects into a Derby db

Question

Hi, Im new to Apache Derby, Id like to know how store a Java Object into a db field.
Im working with the JPCap library and the Packet class has many attributes and values, it will be easier if I could save the complete object in a just one field.
Thanks in advantage.

Answer 1

DB script:
"Create Table APP.PACKETS (ID INTEGER not null primary key, PACKET LONG VARCHAR FOR BIT DATA)"
Test:
import jpcap.packet.TCPPacket;
import java.io.ByteArrayOutputStream;
import java.io.ObjectOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ObjectInputStream;
import java.io.IOException;
private static int increment;
public static void addPacket() {
System.out.println("Inserting...");
TCPPacket packet = new TCPPacket(12, 8080, 56, 78, false, false, false, false, true, true, true, true, 10, 10);
try {
ByteArrayOutputStream byteOutStream = new ByteArrayOutputStream();
ObjectOutputStream objOutStream = new ObjectOutputStream(byteOutStream);
objOutStream.writeObject(packet);
objOutStream.flush();
objOutStream.close();
byteOutStream.close();
PreparedStatement pstmt = conn.prepareStatement("Insert Into APP.PACKETS Values(?, ?)");
pstmt.setInt(1, ++increment) ;
pstmt.setBytes(2, byteOutStream.toByteArray());
pstmt.execute();
conn.commit() ;
System.out.println("Inserted!");
} catch(IOException e) {
e.printStackTrace();
} catch(SQLException e) {
e.printStackTrace();
public static void showPackets() {
String query = "Select * From APP.PACKETS ";
Statement st = null;
ResultSet rs = null;
int id = -1;
byte[] data = null;
try {
st = conn.createStatement();
rs = st.executeQuery(query);
while (rs.next()) {
id = rs.getInt("id") ;
          data = rs.getBytes("packet") ;
ByteArrayInputStream byteInStream = new ByteArrayInputStream(data);
ObjectInputStream objInStream = new ObjectInputStream(byteInStream);
Object obj = objInStream.readObject();
objInStream.close();
byteInStream.close();
if (obj instanceof TCPPacket) {
TCPPacket p = (TCPPacket)obj;
System.out.println(p.dst_port); // Print anything
} else {
System.out.println("No Found!");
} catch(IOException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch(SQLException e) {
e.printStackTrace();
Thats one of several ways to insert Java Objects...