Our AJC member CTC(ITOCHU TECHNO-SCIENCE Corporation) reports
us a strange phenomenon which happens on Java socket under Solaris and Windows.
We guess it may be a bug.

[Background ]
CTC is planing to develop a 3-tier system using Java socket.
The structure is as following:
Clients <-----> Server <-----> Oracle/Sybase

Before they start the developing, they test a small program to
measure performances of Java socket under both OS Solaris and Windows.

They design two patterns which call pattern A (1 client access/ 1 socket create ) and
pattern B (keep socket) and test them between Solaris and the Windows.

pattern A: Socket is created once ServerSocket accepts the client's request, and the server
           will close the socket for every request.

pattern B: Socket is created when the first request is accepted, and the server will keep
           the socket until the whole requests end.

[Phenomenon]
The following is the results under different environments and patterns A, B.

The strange phenomenon is "Test One", because the response time of pattern B
is longer than pattern A.

#The problem is that the results show Sparc/Solaris is not suitable as a Server site
 for 3-tier structure in this case.

The test Java sources are attached at the last. Here is the test steps:
[Step1] Compile the Server.java and Client.java,
[Step2] java Server &
[Step3] java Client aaa ----> if you test pattern A
        java Client ----> if you test oattern B
[Step4] Just view the response time.
        [Step3] will display the time.

Since I test it one my machine called "speed" as the server site, you should change it to
your test machine name at the source Client.java.

(1) Case One
[Environment]
Server: Solaris 8, "Solaris_JDK_1.2.1_04c"
Client: Windows 95, java full version "1.3.0-c"

[Results]
            pattern A (1 client access/ 1 socket create ) pattern B case (keep socket)
test 1 16260 (msec) 101010 (msec)
test 2 15650 100900
test 3 14780 100950

--------------------------------------------------------------------------
(2) Case Two
[Environment]
Server: Solaris 8, Solaris_JDK_1.2.1_04c
Client: Solaris 8, Solaris_JDK_1.2.1_04c

[Results]
            pattern A (1 client access/ 1 socket create ) pattern B case (keep socket)
test 1 5064 2038
test 2 4866 2044
test 3 4898 2065
   
---------------------------------------------------------------------------
(3) Case Three
[Environment]
Server: Windows 95, java full version "1.3.0-c"
Client: Solaris 8, "Solaris_JDK_1.2.1_04c"

[Results]
            pattern A (1 client access/ 1 socket create ) pattern B case (keep socket)
test 1 11396 6216
test 2 11415 5807
test 3 11901 5857
---------------------------------------------------------------------------


//Client.java start--------------------------------------------------------------------------------

import java.io.*;
import java.net.*;
import java.util.*;

public class Client {

  private String server = "speed"; // ---> You should change it to your server name.
  private int port = 4567;
  private int timeout = 0;

  // Socket
  private Socket socket;
  private BufferedReader is;
  private BufferedWriter os;

  public Client() {
    try {
      socket = new Socket(server, port);
      os = new BufferedWriter(
new OutputStreamWriter(socket.getOutputStream()));
      is = new BufferedReader(
new InputStreamReader(socket.getInputStream()));
      if (timeout > 0)
socket.setSoTimeout(timeout * 1000);
    } catch (UnknownHostException e) {
      e.printStackTrace();
    } catch (UnknownServiceException e) {
      e.printStackTrace();
    } catch (SocketException e) {
      e.printStackTrace();
    } catch (IOException e) {
      e.printStackTrace();
    }
// System.out.println("Local Port " + socket.getLocalPort());
  }

  private void close() {
// System.out.println("Client close()");
    try {
      os.write("close()\n", 0, 8);
      os.flush();
      is.close();
      os.close();
      socket.close();
      is = null;
      os = null;
      socket = null;
    } catch (IOException e) {}
  }

  /*
   * Send command string to server, and receive the data from server.
   * @param sbuff Buffer contain the send data
   * @param rbuff Buffer contain the received data
   * @return status.
   */
  public void send() {
    // Send request to server and receive the return data.
    try {
      String s = "Send request to server.";
      for (int i = 0; i < 100; ++i)
os.write(s, 0, s.length());
      os.write("\n", 0, 1);
      os.flush();
      String r = is.readLine();
// System.out.println(r);
    } catch (InterruptedIOException e) {
      System.out.println(e);
    } catch (IOException e) {
      System.out.println(e);
    }
  }

  public static void main(String [] args) {
    int count = 1000;
    Date s1 = new Date();
    if (args.length <= 0) {
      System.out.println("pattern B case (keep socket): count = " + count);
      Client client = new Client();
      for (int i = 0; i < count; ++i) {
client.send();
      }
      client.close();
    } else {
      System.out.println("pattern A (1 client access/ 1 socket create ): count = " + count);
      for (int i = 0; i < count; ++i) {
Client client = new Client();
client.send();
client.close();
      }
    }
    Date s2 = new Date();
    System.out.println("Time " + String.valueOf(s2.getTime()-s1.getTime()));
  }
}
// Client.java end------------------------------------------------------------------------------


// Server.java start------------------------------------------------------------------------------
import java.util.Date;
import java.io.IOException;
import java.net.*;
import java.io.*;

public class Server extends Thread {
  private int id;
  private Socket socket;
  private BufferedReader is;
  private BufferedWriter os;

  public Server(Socket sock, int no) throws IOException {
// System.out.println("Open server " + no);
    id = no;
    socket = sock;
    is = new BufferedReader(
      new InputStreamReader(socket.getInputStream()));
    os = new BufferedWriter(
new OutputStreamWriter(socket.getOutputStream()));
// System.out.println("rec=" + socket.getReceiveBufferSize() +
// " Send=" + socket.getSendBufferSize());
  }

  /**
   * Run thread
   */
  public void run() {
// Date t1 = new Date();
// Date t2 = t1;
    int i = 0;
    for (;;) {
      try {
++i;
        Thread.yield();
String r = is.readLine();
// System.out.println("ID=" + id + " I=" + i + " Length=" + r.length());
if ("close()".equals(r))
break;
String s = String.valueOf(id) + "\n";
os.write(s, 0, s.length());
os.flush();
// Date t3 = new Date();
// System.out.println("T=" + (t3.getTime()-t2.getTime()));
// t2 = t3;
      } catch (IOException e) {
e.printStackTrace();
      }
    }
    try {
      socket.close();
    } catch (IOException e) {
      e.printStackTrace();
    }
// t2 = new Date();
// System.out.println("Time=" + (t2.getTime()-t1.getTime()));
 // System.out.println("Server closed " + id);
  } // run

  public static void main(String [] args) {
    try {
      int no = 0;
      int port = 4567;
      ServerSocket server = new ServerSocket(port);
      System.out.println(" Port: " + server.getLocalPort());

      while (true) {
try {
          Thread.yield();
Server ss = new Server(server.accept(), no);
no++;
ss.start();
} catch (IOException e) {
e.printStackTrace();
}
      }
    } catch (IOException e) {
      e.printStackTrace();
    }
  }

} // class Server
// Server.java end------------------------------------------------------------------------------