科技行者

行者学院 转型私董会 科技行者专题报道 网红大战科技行者

知识库

知识库 安全导航

至顶网软件频道Java实现POP3服务器

Java实现POP3服务器

  • 扫一扫
    分享文章到微信

  • 扫一扫
    关注官方公众号
    至顶头条

  //write --1998

作者:中国IT实验室 来源:中国IT实验室 2007年9月9日

关键字: 69826 编程 java

  • 评论
  • 分享微博
  • 分享邮件

  //write --1998.6
  
  import java.net.*;
  
  import java.util.*;
  
  public class pop3server{
  
  private static final int SERVER_PORT=110;
  
  private static final int MAX_CLIENT=500;
  
  private ServerSocket listenSocket=null;
  
  private boolean keeprunning=true;
  
  private InetAddress ip;
  
  public static void main(String[] args){
  
  pop3server server=new pop3server();
  
  server.impserver();
  
  }
  
  public void impserver(){
  
  Socket clientSocket=null;
  
  try{
  
  while(keeprunning){
  
  clientSocket=listenSocket.accept();
  
  int numThreads=Thread.activeCount();
  
  System.out.println(numThreads);
  
  manageconnection newhandle=new manageconnection(clientSocket);
  
  Thread newhandlethread=new Thread(newhandle);
  
  newhandlethread.start();
  
  System.out.println("hello");
  
  }
  
  }
  
  catch(IOException excpt){
  
  System.err.println("Sorry ,Failed I/O:"+excpt);
  
  }
  
  }
  
  public pop3server()
  
  {
  
  try{
  
  listenSocket=new ServerSocket(SERVER_PORT,MAX_CLIENT);
  
  }catch(IOException excpt){
  
  System.err.println("SOrry to open port "+SERVER_PORT+":"+excpt);
  
  System.exit(1);
  
  }
  
  }
  
  }
  
  /*follow is manage and process command class*/
  
  class manageconnection implements Runnable{
  
  private static final boolean AUTOFLUSH=true;
  
  private Socket mySocket=null;
  
  private PrintWriter out=null;
  
  private BufferedReader in=null;
  
  private boolean checkedpass=false;
  
  private int msgnum=0;
  
  private long[] msgsize=new long[100];
  
  private long totalsize=0;
  
  private String username=null;
  
  public manageconnection(Socket newSocket){
  
  mySocket=newSocket;
  
  }
  
  public void run(){
  
  String nextline=null;
  
  String password;
  
  int check=0;
  
  int strlen;
  
  String content="Subject:hello";
  
  String command=null;
  
  String auth_user="user";
  
  String arg1;
  
  int arg2=0;
  
  String arg3;
  
  int i=0;
  
  int count=0;
  
  int time=0;
  
  try{Thread.currentThread().sleep(10);
  
  }catch(Exception e){
  
  System.out.println(e);
  
  }
  
  try{
  
  mySocket.setTcpNoDelay(true);
  
  time=mySocket.getSoTimeout();
  
  }catch(SocketException excpt){
  
  System.out.println(excpt);
  
  }
  
  try{
  
  out=new PrintWriter(mySocket.getOutputStream(),AUTOFLUSH);
  
  in=new BufferedReader(new InputStreamReader(mySocket.getInputStream())
  
  
  );
  
  /*System.out.println("hello thread1");*/
  
  out.println("+OK"+" TianHua's pop3 server");
  
  try{
  
  while(true){
  
  if(check!=3){
  
  try{
  
  nextline=in.readLine();}catch(Exception excpt){
  
  System.out.println("sorry:"+excpt);
  
  break;
  
  }
  
  System.out.println(count+" "+nextline);
  
  if(nextline.length()<4){
  
  out.println("-ERR");
  
  }else{
  
  command=nextline.substring(0,4);
  
  if(command.equalsIgnoreCase("user")){
  
  i=1;
  
  }
  
  if(command.equalsIgnoreCase("pass")){
  
  i=2;
  
  }
  
  if(command.equalsIgnoreCase("stat")){
  
  i=3;
  
  }
  
  if(command.equalsIgnoreCase("quit")){
  
  i=4;
  
  }
  
  if(command.equalsIgnoreCase("list")){
  
  i=5;
  
  }
  
  if(command.equalsIgnoreCase("retr")){
  
  i=6;
  
  }
  
  if(command.equalsIgnoreCase("dele")){
  
  i=7;
  
  }
  
  switch(i){
  
  case 1:if(check==0){
  
  check=1;
  
  if(nextline.length()<5){
  
  out.println("-ERR");
  
  }else{arg1=nextline.substring(5);
  
  username=arg1;
  
  out.println("+OK");
  
  }
  
  }else{out.println("-ERR");}
  
  i=0;
  
  break;
  
  case 2:if(check==1){
  
  if(nextline.length()<5){
  
  out.println("-ERR");
  
  }else{
  
  arg1=nextline.substring(5);
  
  password=arg1;
  
  if(check(username,password)=='1'){
  
  check=2;
  
  /*msgnum=readmail(username);*/
  
  out.println("+OK");}else{
  
  out.println("-ERR"+" sorry auth failed");
  
  check=0;}
  
  }
  
  }else{out.println("-ERR");}
  
  i=0;
  
  break;
  
  case 3:if(check==2){
  
  msgnum=readmail(username);
  
  out.println("+OK"+" "+msgnum+" "+totalsize);
  
  }else{
  
  out.println("-ERR");
  
  }
  
  i=0;
  
  break;
  
  case 4:out.println("+OK BYE BYE welcome to TianHua's Mail System next
  
  
  time");
  
  check=3;
  
  i=0;
  
  break;
  
  case 5:if(check==2){
  
  out.println("+OK");
  
  out.println(msgnum+" "+totalsize);
  
  int ii,iii=0;
  
  for(ii=1;ii<=msgnum;ii++){
  
  out.println(ii+" "+msgsize[iii]);
  
  iii++;
  
  }
  
  out.println(".");
  
  }else{
  
  out.println("-ERR");
  
  }
  
  i=0;
  
  break;
  
  case 6:if(check==2){
  
  if(nextline.length()<5){
  
  out.println("-ERR");
  
  }else{
  
  arg1=nextline.substring(5);
  
  out.println("+OK");
  
  System.out.println(arg1);
  
  printmail(Integer.parseInt(arg1),username);
  
  out.print("\r\n");
  
  out.print(".");
  
  out.print("\r\n");
  
  boolean st=out.checkError();
  
  System.out.println(st);
  
  /*if(nextline.length()<6){
  
  out.println("-ERR");
  
  }else{
  
  try{
  
  arg2=Integer.parseInt(nextline.substring(5));
  
  }catch(NumberFormatException except)
  
  {
  
  out.println("-ERR");
  
  break;
  
  }
  
  if(msgnum==0){
  
  out.println("-ERR no msg retrived");
  
  }
  
  if(arg2<=msgnum){
  
  out.println("+OK");
  
  out.println(content);
  
  out.println("");
  
  out.print(".");
  
  out.println();
  
  out.println(".");
  
  System.out.println("msg finished");
  
  }else{
  
  out.println("no such msg");
  
  }
  
  }*/
  
  }
  
  }else{out.println("-ERR");
  
  }
  
  i=0;
  
  System.out.println("retr finished");
  
  break;
  
  case 7:if(check==2){
  
  out.println("+OK");
  
  }else{
  
  out.println("-ERR");
  
  }
  
  i=0;
  
  break;
  
  default:out.println("-ERR");
  
  i=0;
  
  break;
  
  }
  

查看本文来源

    • 评论
    • 分享微博
    • 分享邮件
    邮件订阅

    如果您非常迫切的想了解IT领域最新产品与技术信息,那么订阅至顶网技术邮件将是您的最佳途径之一。

    重磅专题
    往期文章
    最新文章