Compressed objects over socket

Question

The simplest example on a tutorial http://java.sun.com/developer/technicalArticles/Programming/compression/ does work:
// write to client
GZIPOutputStream gzipout = new
  GZIPOutputStream(socket.getOutputStream());
ObjectOutputStream oos = new
  ObjectOutputStream(gzipout);
oos.writeObject(obj);
gzipout.finish();However, what shoul be the correct way for sending/receiving multiple objects in a socket write/read loop?
Here's an SSCCE that fails with every conceivable tweak, conceived by my weak brain.
/* server */
import java.net.*;
import java.io.*;
import java.util.*;
import java.util.zip.*;
public class LoopServer{
  public static void main(String[] args) throws Exception{
    ServerSocket ss = new ServerSocket(9999);
    Socket cs = ss.accept();
    System.out.println("client accepted");
    GZIPOutputStream gos =  new GZIPOutputStream(cs.getOutputStream());
    ObjectOutputStream oos = new ObjectOutputStream(gos);
    ObjectInputStream ois
      = new ObjectInputStream(new GZIPInputStream(cs.getInputStream()));
    int count = 0;
System.out.println("begin loop"); // never comes here
    while (++count < 30){
      oos.writeObject(new Date());
      gos.finish();
      oos.flush();
      System.out.println((Date)(ois.readObject()));
    cs.close();
/* client */
import java.net.*;
import java.io.*;
import java.util.*;
import java.util.zip.*;
public class LoopClient{
  public static void main(String[] args) throws Exception{
    Socket cs = new Socket("localhost", 9999);
    GZIPOutputStream gos =  new GZIPOutputStream(cs.getOutputStream());
    ObjectOutputStream oos = new ObjectOutputStream(gos);
    ObjectInputStream ois
      = new ObjectInputStream(new GZIPInputStream(cs.getInputStream()));
      System.out.println((Date)(ois.readObject()));
    int count = 0;
System.out.println("begin loop"); // never comes here
    while (++count < 30){
      System.out.println((Date)(ois.readObject()));
      oos.writeObject(new Date());
      gos.finish();
      oos.flush();
    cs.close();
}

Answer 1

ejp wrote:
Isn't there a way to prevent that? Not unless you write a subclass of OOS which breaks the rules for writing finalizers, which you don't want to do either ...OK. I think I have come up with a sound hack that can avert the finalizer risk of socket closing.
According to another thread:
http://forum.java.sun.com/thread.jspa?threadID=5274508
Ejp's recommended method did work for receiving a single byte array while my method which uses ByteArrayOutputStream and its toByteArray() didn't.
Question: When the sender has sent a single byte array at a burst, should the receiver not use fragmentary read() or read(byte[smallsize])?. Should the receiver only use read(byte[fullsize])? If the answer is yes, then it would explain the cause of the above 'didn't work' failure.
/* server */
import java.net.*;
import java.io.*;
import java.util.*;
import java.util.zip.*;
public class LoopServer5{
  public static void main(String[] args) throws Exception{
    OutputStream os;
    InputStream is;
    ByteArrayOutputStream baos;
    ByteArrayInputStream bais;
    GZIPOutputStream gos;
    ObjectOutputStream oos;
    ObjectInputStream ois;
    DataOutputStream dos;
    DataInputStream dis;
    ServerSocket ss = new ServerSocket(9999);
    Socket cs = ss.accept();
    System.out.println("client accepted");
    os = cs.getOutputStream();
    is = cs.getInputStream();
    dos = new DataOutputStream(os);
    dis = new DataInputStream(is);
    int count = 0;
    int d;
    while (++count <= 10){
      /* in order to avert using multiple disposable OOS
       * wrapping a GOS wrapping the Socket OS in turn,
       * the Socket OS simply send a byte array as a DOS
       * thereby averting the risk of Socket OS finalization
      baos = new ByteArrayOutputStream();
      gos = new GZIPOutputStream(baos);
      oos = new ObjectOutputStream(gos);
      oos.writeObject(new Date());
      gos.finish();
      oos.close();
      byte[] ba = baos.toByteArray();
      dos.writeInt(ba.length); // ejp's recommended way of doing things  marked #
      dos.write(ba);                // #
      dos.flush();                    // #
      int size = dis.readInt();  // #
      byte[] buf = new byte[size]; // #
      dis.readFully(buf); // # simply read a byte array, not an Object
      bais = new ByteArrayInputStream(buf);
      // create an OIS from the byte array received
      // what a clever hack! ...self-praise!
      ois = new ObjectInputStream(new GZIPInputStream(bais));
      System.out.println
        ("from client: " + (Date)(ois.readObject()) + " " + count);
    cs.close();
/* client */
import java.net.*;
import java.io.*;
import java.util.*;
import java.util.zip.*;
public class LoopClient5{
  public static void main(String[] args) throws Exception{
    OutputStream os;
    InputStream is;
    ByteArrayOutputStream baos;
    ByteArrayInputStream bais;
    GZIPOutputStream gos;
    ObjectOutputStream oos;
    ObjectInputStream ois;
    DataOutputStream dos;
    DataInputStream dis;
    Socket cs = new Socket("localhost", 9999);
    os = cs.getOutputStream();
    is = cs.getInputStream();
    dos = new DataOutputStream(os);
    dis = new DataInputStream(is);
    int count = 0;
    int d;
    while (++count <= 10){
      int size = dis.readInt();
      byte[] buf = new byte[size];
      dis.readFully(buf);
      bais = new ByteArrayInputStream(buf);
      ois = new ObjectInputStream(new GZIPInputStream(bais));
      System.out.println
        ("from server: " + (Date)(ois.readObject()) + " " + count);
      baos = new ByteArrayOutputStream();
      gos = new GZIPOutputStream(baos);
      oos = new ObjectOutputStream(gos);
      oos.writeObject(new Date());
      gos.finish();
      oos.close();
      byte[] ba = baos.toByteArray();
      dos.writeInt(ba.length);
      dos.write(ba);
      dos.flush();
    cs.close();
}