netc.java

Java程序设计技巧与开发实例附书源代码。

import java.net.*;
import java.io.*;
import java.awt.*;
import java.lang.*;

public class Netc
{
   static Socket sock[]; //define an arrary of socket
   static InetAddress Serveraddr[];
   // define an arrary to hold the IP address of
   // all the servers
   static DataInputStream datain[]; //define an arrary of input stream
   static DataOutputStream dataout[];
   static int NumServers;

   public static void main(String args[]) throws IOException
   {
      int i;
      DataInputStream ServerConfigFile; /* for server config file */
      String IntString = null, Servernames[];

      ServerConfigFile = new DataInputStream(new FileInputStream("srvcfg.txt"));

      try
      {
         IntString = ServerConfigFile.readLine();
      }
      catch (IOException ioe)
      {
         System.out.println("Error reading the # servers");
         System.exit(1);
      }

      try
      {
         NumServers = Integer.parseInt(IntString); //string to int
      }
      catch (NumberFormatException nfe)
      {
         System.out.println(" r servers is not an interger.");
         System.exit(1);
      }

      // now we know number of servers, we can instantiate the arrarys
      Servernames = new String[NumServers];
      sock = new Socket[NumServers];
      Serveraddr = new InetAddress[NumServers];
      datain = new DataInputStream[NumServers];
      dataout = new DataOutputStream[NumServers];

      for (i = 0; i < NumServers; i++)
      {
         try
         {
            Servernames[i] = ServerConfigFile.readLine();
         }
         catch (IOException e)
         {
            System.out.println("Error reading server names");
            System.exit(1);
         }
         Servernames[i] = Servernames[i].trim();
      }

      try
      {
         ServerConfigFile.close();
      }
      catch (IOException e)
      {
         System.out.println("Error reading server names");
         System.exit(1);
      }

      // open socket to the server and setup the stream
      try
      {
         for (i = 0; i < NumServers; i++)
         { //get IP address
            Serveraddr[i] = InetAddress.getByName(Servernames[i]);
            sock[i] = new Socket(Serveraddr[i], 1237);
            datain[i] = new DataInputStream(
                new BufferedInputStream(sock[i].getInputStream()));
            dataout[i] = new DataOutputStream(
                new BufferedOutputStream(sock[i].getOutputStream()));
         }
         ;
      }
      catch (IOException E)
      {
         System.out.println("I/O Error openning stream sockets.");
         System.exit(1);
      }
      //call the client body procedure to solve problem
      ClientBody();
      try
      { //close all streams and sockets
         for (i = 0; i < NumServers; i++)
         {
            dataout[i].close();
            datain[i].close();
            sock[i].close();
         }
         ;
      }
      catch (IOException E)
      {
         System.out.println("error closing streams and Sockets");
         System.exit(1);
      }
   }

   public static void ClientBody() throws IOException
   {

      int i, j, k;
      int TotNum = 0, NumRows = 0;
      int A[][], B[][], C[][];

      DataInputStream ClientConfigFile;
      String IntString = null;

      ClientConfigFile = new DataInputStream(
          new FileInputStream("clicfg.txt"));

      try
      {
         IntString = ClientConfigFile.readLine();
      }
      catch (IOException ioe)
      {
         System.out.println("error reading N from file.");
         System.exit(1);
      }

      try
      {
         TotNum = Integer.parseInt(IntString); //string to integer
      }
      catch (NumberFormatException nfe)
      {
         System.out.println("the value for N is not an integer.");
         System.exit(1);
      }

      try
      {
         ClientConfigFile.close();
      }
      catch (IOException e)
      {
         System.out.println("I/O error closing config file.");
         System.exit(1);
      }

      NumRows = TotNum / NumServers;

      A = new int[TotNum][TotNum];
      B = new int[TotNum][TotNum];
      C = new int[TotNum][TotNum];

      for (i = 0; i < TotNum; i++)
      {
         for (j = 0; j < TotNum; j++)
         {
            A[i][j] = i;
            B[i][j] = j;
            C[i][j] = 0;
         }
      }

      System.out.println("Sending information to servers.");

      try
      {
         for (i = 0; i < NumServers; i++)
         {
            dataout[i].write(TotNum);
            dataout[i].write(NumRows);
            dataout[i].flush();

            for (j = NumRows * i; j < NumRows * (i + 1); j++)
            {
               for (k = 0; k < TotNum; k++)
               {
                  dataout[i].writeInt(A[j][k]);
               }
            }
            dataout[i].flush();

            for (j = 0; j < TotNum; j++)
            {
               for (k = 0; k < TotNum; k++)
               {
                  dataout[i].writeInt(B[j][k]);
               }
            }
            dataout[i].flush();
         }
         ;
      }
      catch (IOException ioe)
      {
         System.out.println("I/O error reading matrix to server");
         System.exit(1);
      }

      try
      {
         for (i = 0; i < NumServers; i++)
         {
            for (j = NumRows * i; j < NumRows * (i + 1); j++)
            {
               for (k = 0; k < TotNum; k++)
               {
                  C[j][k] = datain[i].readInt();
               }
            }
         }
      }
      catch (IOException ioe)
      {
         System.out.println("I/O error receiving result from server");
         System.exit(1);
      }
      System.out.println();
      System.out.println("Resultant Matrix");
      System.out.println();

      for (i = 0; i < TotNum; i++)
      {
         for (j = 0; j < TotNum; j++)
         {
            System.out.print(C[i][j] + " ");
         }
         System.out.println();
      }
   }
}