Programming Languages Research Group: Git - IRC.git/blob

   1 public class QueryThread extends Thread {
   2     QueryQueue toprocess;
   3     QueryList ql;
   4     public QueryThread(QueryQueue qq, QueryList ql) {
   5         toprocess=qq;
   6         this.ql=ql;
   7     }
   8
   9     public void run() {
  10         while(true) {
  11             Query q=null;
  12             while(q==null) {
  13                 q=toprocess.getQuery();
  14                 if (q==null)
  15                     Thread.sleep(2);
  16             }
  17             String hostname=q.getHostName();
  18             System.printString("Processing ");
  19             System.printString(hostname);
  20             System.printString(" ");
  21             System.printString(q.getPath());
  22             System.printString("\n");
  23             Socket s=new Socket(hostname, 80);
  24             requestQuery(q, s);
  25             readResponse(q, s);
  26             q.outputFile();
  27             processPage(q, ql);
  28             s.close();
  29         }
  30     }
  31
  32     void requestQuery(Query q, Socket sock) {
  33         StringBuffer req=new StringBuffer("GET ");
  34         req.append("/");
  35         req.append(q.getPath());
  36         req.append(" HTTP/1.1\r\nHost:");
  37         req.append(q.getHostName());
  38         req.append("\r\n\r\n");
  39         sock.write(req.toString().getBytes());
  40     }
  41
  42     void readResponse(Query q, Socket sock) {
  43         //    state 0 - nothing
  44         //    state 1 - \r
  45         //    state 2 - \r\n
  46         //    state 3 - \r\n\r
  47         //    state 4 - \r\n\r\n
  48         int state=0;
  49         while(true) {
  50             if (state<4) {
  51                 if (state==0) {
  52                     byte[] b=new byte[1];
  53                     int numchars=sock.read(b);
  54                     if ((numchars==1)) {
  55                         if (b[0]=='\r') {
  56                             state++;
  57                         }
  58                     } else
  59                         return;
  60                 } else if (state==1) {
  61                     byte[] b=new byte[1];
  62                     int numchars=sock.read(b);
  63                     if (numchars==1) {
  64                         if (b[0]=='\n')
  65                             state++;
  66                         else
  67                             state=0;
  68                     } else return;
  69                 } else if (state==2) {
  70                     byte[] b=new byte[1];
  71                     int numchars=sock.read(b);
  72                     if (numchars==1) {
  73                         if (b[0]=='\r')
  74                             state++;
  75                         else
  76                             state=0;
  77                     } else return;
  78                 } else if (state==3) {
  79                     byte[] b=new byte[1];
  80                     int numchars=sock.read(b);
  81                     if (numchars==1) {
  82                         if (b[0]=='\n')
  83                             state++;
  84                         else
  85                             state=0;
  86                     } else return;
  87                 }
  88             } else {
  89                 byte[] buffer=new byte[1024];
  90                 int numchars=sock.read(buffer);
  91                 if (numchars==0)
  92                     return;
  93                 else {
  94                     String curr=(new String(buffer)).subString(0,numchars);
  95                     q.response.append(curr);
  96                 }
  97             }
  98         }
  99     }
 100
 101     void processPage(Query q, QueryList ql) {
 102         int index=0;
 103         String href=new String("href=\"");
 104         String searchstr=q.response.toString();
 105         boolean cont=true;
 106         while(cont) {
 107             int mindex=searchstr.indexOf(href,index);
 108             if (mindex!=-1) {
 109
 110                 int endquote=searchstr.indexOf('"', mindex+href.length());
 111                 if (endquote!=-1) {
 112                     String match=searchstr.subString(mindex+href.length(), endquote);
 113                     String match2=q.makewebcanonical(match);
 114                     if (match2!=null&&!ql.checkQuery(match2)) {
 115                         ql.addQuery(match2);
 116                         System.printString(q.getHostName(match));
 117                         System.printString("        ");
 118                         System.printString(q.getPathName(match));
 119                         System.printString("\n");
 120                         Query newq=new Query(q.getHostName(match), q.getPathName(match));
 121                         toprocess.addQuery(newq);
 122                     }
 123                     index=endquote;
 124                 } else cont=false;
 125             } else cont=false;
 126         }
 127     }
 128
 129 }