Programming data interface

Question

Hello,
I am pretty new at java programming and I have to write an interface with an external system sending data to our system in some ValueObject formats. I want to create my own Object for interface purposes, but I
don't have a clue what to use: Vector, HashTable, Array???
The structure I would like to have is as follows:
OBJECT: -> tableName (String)
-> Records -> Record1 ->Field1 ->fieldName
->fieldValue
->fieldType
->fieldFormat
->Field2 ->fieldName
->fieldValue
->fieldType
->fieldFormat
->...
->Fieldn
-> Record2 ->Field1...
-> Record3
-> ...
-> Recordn
So, the number of records is unknown and the number of fields is also
unknown as this can be for different database tables.
If anybody could help me with this I would be really greatful...
Or if somebody already did something like this and can give me some
example code, also very helpful!
Or maybe if you would have a better idea than my structure to create
an object containing data that has to be inserted in a database table
let me know!
Thanks a lot,
Sven

Answer 1

The following is a fairly simple way of doing something similar to what you want to do. However it assumes that you are being sent an ObjectStream (If not then the AField will have to change so that it reads the different types of data and then converts to a string)
It also depends on the mark operation which I fear may not be suppprted for ObjectInputStreams.
This code probably won't do what you want it to do, but I hope it should give a good starting point.
-Philip.
import java.util.*;
import java.io.*;
class AField {
    String name;
    String value;
    String type;
    String format;
    public int hashCode(){
        return name.hashCode();
    public static AField readAField(ObjectInputStream in){
        AField toReturn = new AField();
        try{
            toReturn.name = (String)in.readObject();
            toReturn.value = (String)in.readObject();
            toReturn.type = (String)in.readObject();
            toReturn.format = (String)in.readObject();
            return toReturn;
        }catch (Exception e){
            return null;
class ARecord{
    Set fields = new HashSet();
    public static ARecord readARecord(ObjectInputStream in){
        ARecord toReturn = new ARecord();
        boolean finished = false;
        try{
            while (!finished){
                in.mark(4096);
                AField temp = AField.readAField(in);
                if (toReturn.fields.contains(temp)){
                    in.reset();
                    finished = true;
                } else
                    toReturn.fields.add(temp);
        }catch (Exception e) {}
        return toReturn;
class Table {
    ArrayList records = new ArrayList();
    String name;
    public static Table readTable(ObjectInputStream in){
        Table toReturn = new Table();
        try{
            toReturn.name = (String)in.readObject();
            while (in.available() !=0){
                toReturn.records.add(ARecord.readARecord(in));
        }catch (Exception e){}
        return toReturn;