一个简单的网络机器人例子(Java)
import java.awt.*;
import java.net.*;
import java.io.*;
import java.lang.*;
import java.util.*;
class node{
private Object data;
private node next;
private node prev;
public node(Object o){
data = o;
prev = next = null;
}
public String toString(){
if(next!=null)return data.toString() + " "+ next.toString();
return data.toString();
}
public node getNext(){return next;}
public void setNext(node n){next = n;}
public node getPrev(){return prev;}
public void setPrev(node n){prev = n;}
public Object getData(){return data;}
}
class linkedlist{
node head;
node tail;
public linkedlist(){
tail = head = null;
}
public String toString(){
if(head==null)return "Empty list";
return head.toString();
}
public void insert(Object o){
if(tail==null){
head = tail = new node(o);
}else{
node nn = new node(o);
tail.setNext(nn);
tail=nn;
}
}
public boolean contains(Object o){
for(node n = head;n!=null;n=n.getNext()){
if(o.equals(n.getData()))return true;
}
return false;
}
public Object pop(){
if(head==null)return null;
Object ret = head.getData();
head = head.getNext();
if(head==null)tail = null;
return ret;
}
public boolean isEmpty(){
return head==null;
}
}
class list{
protected node tail;
protected node ptr;
private boolean stop;
public list(){
ptr=tail=null;
stop=false;
}
public boolean isEmpty(){return tail==null;}
public void reset(){
stop=false;
ptr=tail;
}
public String toString(){
if(tail==null)return "Empty list";
String ret="";
for(node n = tail.getNext();n!=tail;n=n.getNext())ret+=n.getData().toString()+" ";
ret+=tail.getData().toString();
return ret;
}
public Object get(){
if(ptr==null)return null;
ptr = ptr.getNext();
if(ptr==tail.getNext()){
if(stop)return null;
stop=true;
return tail.getNext().getData();
}
return ptr.getData();
}
public void insert(Object o, boolean attail){
node nn = new node(o);
if(tail==null){
nn.setNext(nn);
nn.setPrev(nn);
ptr=tail=nn;
return;
}
if(attail){
tail.getNext().setPrev(nn);
nn.setNext(tail.getNext());
tail.setNext(nn);
nn.setPrev(tail);
tail=nn;
}else{
nn.setNext(tail.getNext());
nn.setPrev(tail);
tail.setNext(nn);
nn.getNext().setPrev(nn);
}
}
public void insert(Object o){}
}
class stack extends list{
public stack(){super();}
public void insert(Object o){insert(o, false);}
}
class queue extends list{
public queue(){super();}
public void insert(Object o){insert(o, true);}
public String peek(){
if(tail==null)return "";
return tail.getNext().getData().toString();
}
public Object pop(){
if(tail==null)return null;
Object ret = tail.getNext().getData();
if(tail.getNext()==tail){
tail=ptr=null;
}else{
if(tail.getNext()==ptr)ptr=ptr.getNext();
tail.setNext(tail.getNext().getNext());
}
return ret;
}
}
class hashtable{
private Vector table;
private int size;
public hashtable(){
size = 991;
table = new Vector();
for(int i=0;i<size;i++){
table.add(new linkedlist());
}
}
public void insert(Object o){
int index = o.hashCode();
index = index % size;
if(index<0)index+=size;
linkedlist ol = (linkedlist)table.get(index);
ol.insert(o);
}
public boolean contains(Object o){
int index = o.hashCode();
index = index % size;
if(index<0)index+=size;
return ((linkedlist)(table.get(index))).contains(o);
}
public String toString(){
String ret ="";
for(int i=0;i<size;i++){
if(!((linkedlist)(table.get(i))).isEmpty()){
ret+=" ";
ret+=table.get(i).toString();
}
}
return ret;
}
}
问题点数：0、回复次数：4Top
1 楼xiao7cn（o(∩_∩)o... 哈哈!）回复于 2006-11-06 17:24:59 得分 0
class spider implements Runnable{
public queue todo;
public stack done;
public stack errors;
public stack omittions;
private hashtable allsites;
private String last="";
int maxsites;
int visitedsites;
int TIMEOUT;
String base;
String []badEndings2 = {"ps", "gz"};
String []badEndings3 = {"pdf", "txt", "zip", "jpg", "mpg", "gif", "mov", "tut", "req", "abs", "swf", "tex", "dvi", "bin", "exe", "rpm"};
String []badEndings4 = {"jpeg", "mpeg"};
public spider(String starturl, int max, String b){
TIMEOUT = 5000;
base = b;
allsites = new hashtable();
todo = new queue();
done = new stack();
errors = new stack();
omittions = new stack();
try{
URL u = new URL(starturl);
todo.insert(u);
}catch(Exception e){
System.out.println(e);
errors.insert("bad starting url "+starturl+", "+e.toString());
}
maxsites = max;
visitedsites = 0;
}
/*
* how many millisec to wait for each page
*/
public void setTimer(int amount){
TIMEOUT = amount;
}
/*
* strips the ′#′ anchor off a url
*/
private URL stripRef(URL u){
try{
return new URL(u.getProtocol(), u.getHost(), u.getPort(), u.getFile());
}catch(Exception e){return u;}
}
/*
* adds a url for future processing
*/
public void addSite(URL toadd){
if(null!=toadd.getRef())toadd = stripRef(toadd);
if(!allsites.contains(toadd)){
allsites.insert(toadd);
if(!toadd.toString().startsWith(base)){
omittions.insert("foreign URL: "+toadd.toString());
return;
}
if(!toadd.toString().startsWith("http") && !toadd.toString().startsWith("HTTP")){
omittions.insert("ignoring URL: "+toadd.toString());
return;
}
String s = toadd.getFile();
String last="";
String []comp={};
if(s.charAt(s.length()-3)==′.′){
last = s.substring(s.length()-2);
comp = badEndings2;
}else if(s.charAt(s.length()-4)==′.′){
last = s.substring(s.length()-3);
comp = badEndings3;
}else if(s.charAt(s.length()-5)==′.′){
last = s.substring(s.length()-4);
comp = badEndings4;
}
for(int i=0;i<comp.length;i++){
if(last.equalsIgnoreCase(comp[i])){//loop through all bad extensions
omittions.insert("ignoring URL: "+toadd.toString());
return;
}
}
todo.insert(toadd);
}
}
/*
* true if there are pending urls and the maximum hasn′t been reached
*/
public boolean hasMore(){
return !todo.isEmpty() && visitedsites<maxsites;
}
/*
* returns the next site, works like enumeration, will return new values each time
*/
private URL getNextSite(){
last = todo.peek();
visitedsites++;
return (URL)todo.pop();
}
/*
* Just to see what we are doing now...
*/
public String getCurrent(){
return last;
}
/*
* process the next site
*/
public void doNextSite(){
URL current = getNextSite();
if(current==null)return;
try{
//System.err.println("Processing #"+visitedsites+": "+current);
parse(current);
done.insert(current);
}
catch(Exception e){
errors.insert("Bad site: "+current.toString()+", "+e.toString());
}
}
public void run(){
while(hasMore())doNextSite();
}
/*
* to print out the internal data structures
*/
public String toString(){return getCompleted()+getErrors();}
private String getErrors(){
if(errors.isEmpty())return "No errors ";
else return "Errors: "+errors.toString()+" End of errors ";
}
private String getCompleted(){
return "Completed Sites: "+done.toString()+" End of completed sites ";
}
/*
* Parses a web page at (site) and adds all the urls it sees
*/
private void parse(URL site) throws Exception{
String source=getText(site);
String title=getTitle(source);
if(title.indexOf("404")!=-1 ||
title.indexOf("Error")!=-1 ||
title.indexOf("Not Found")!=-1){
throw new Exception (("404, Not Found: "+site));
}
int loc, beg;
boolean hasLT=false;
boolean hasSp=false;
boolean hasF=false;
boolean hasR=false;
boolean hasA=false;
boolean hasM=false;
boolean hasE=false;
for(loc=0;loc<source.length();loc++){
char c = source.charAt(loc);
if(!hasLT){
hasLT = (c==′<′);
}
//search for "<a "
else if(hasLT && !hasA && !hasF){
if(c==′a′ || c==′A′)hasA=true;
else if(c==′f′ || c==′F′)hasF=true;
else hasLT=false;
}else if(hasLT && hasA && !hasF && !hasSp){
if(c==′ ′ || c==′ ′ || c==′ ′)hasSp=true;
else hasLT = hasA = false;
}
//search for "<frame "
else if(hasLT && hasF && !hasA && !hasR){
if(c==′r′ || c==′R′)hasR=true;
else hasLT = hasF = false;
}else if(hasLT && hasF && hasR && !hasA){
if(c==′a′ || c==′A′)hasA=true;
else hasLT = hasF = hasR = false;
}else if(hasLT && hasF && hasR && hasA && !hasM){
if(c==′m′ || c==′M′)hasM=true;
else hasLT = hasF = hasR = hasA = false;
}else if(hasLT && hasF && hasR && hasA && hasM && !hasE){
if(c==′e′ || c==′E′)hasE=true;
else hasLT = hasF = hasR = hasA = hasM = false;
}else if(hasLT && hasF && hasR && hasA && hasM && hasE && !hasSp){
if(c==′ ′ || c==′ ′ || c==′ ′)hasSp=true;
else hasLT = hasF = hasR = hasA = hasM = hasE = false;
}
//found "<frame "
else if(hasLT && hasF && hasR && hasA && hasM && hasE && hasSp){
hasLT = hasF = hasR = hasA = hasM = hasE = hasSp = false;
beg = loc;
loc = source.indexOf(">", loc);
if(loc==-1){
errors.insert("malformed frame at "+site.toString());
loc = beg;
}
else{
try{
parseFrame(site, source.substring(beg, loc));
}
catch(Exception e){
errors.insert("while parsing "+site.toString()+", error parsing frame: "+e.toString());
}
}
}
//found "<a "
else if(hasLT && hasA && hasSp && !hasF){
hasLT = hasA = hasSp = false;
beg = loc;
loc = source.indexOf(">", loc);
if(loc==-1){
errors.insert("malformed linked at "+site.toString());
loc = beg;
}
else{
try{
parseLink(site, source.substring(beg, loc));
}
catch(Exception e){
errors.insert("while parsing "+site.toString()+", error parsing link: "+e.toString());
}
}
}
}
}
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2 楼xiao7cn（o(∩_∩)o... 哈哈!）回复于 2006-11-06 17:25:41 得分 0
/*
* parses a frame
*/
private void parseFrame(URL at_page, String s) throws Exception{
int beg=s.indexOf("src");
if(beg==-1)beg=s.indexOf("SRC");
if(beg==-1)return;//doesn′t have a src, ignore
beg = s.indexOf("=", beg);
if(beg==-1)throw new Exception("while parsing "+at_page.toString()+", bad frame, missing ′=′ after src: "+s);
int start = beg;
for(;beg<s.length();beg++){
if(s.charAt(beg)==′′′)break;
if(s.charAt(beg)==′"′)break;
}
int end=beg+1;
for(;end<s.length();end++){
if(s.charAt(beg)==s.charAt(end))break;
}
beg++;
if(beg>=end){//missing quotes... just take the first token after "src="
for(beg=start+1;beg<s.length() && (s.charAt(beg)==′ ′);beg++){}
for(end=beg+1;end<s.length() && (s.charAt(beg)!=′ ′) && (s.charAt(beg)!=′>′);end++){}
}
if(beg>=end){
errors.insert("while parsing "+at_page.toString()+", bad frame: "+s);
return;
}
String linkto=s.substring(beg,end);
if(linkto.startsWith("mailto:")||linkto.startsWith("Mailto:"))return;
if(linkto.startsWith("javascript:")||linkto.startsWith("javascript:"))return;
if(linkto.startsWith("news:")||linkto.startsWith("javascript:"))return;
try{
addSite(new URL(at_page, linkto));
return;
}catch(Exception e1){}
try{
addSite(new URL(linkto));
return;
}catch(Exception e2){}
try{
URL cp = new URL(at_page.toString()+"/index.html");
System.out.println("attemping to use "+cp);
addSite(new URL(cp, linkto));
return;
}catch(Exception e3){}
errors.insert("while parsing "+at_page.toString()+", bad frame: "+linkto+", formed from: "+s);
}
/*
* given a link at a URL, will parse it and add it to the list of sites to do
*/
private void parseLink(URL at_page, String s) throws Exception{
//System.out.println("parsing link "+s);
int beg=s.indexOf("href");
if(beg==-1)beg=s.indexOf("HREF");
if(beg==-1)return;//doesn′t have a href, must be an anchor
beg = s.indexOf("=", beg);
if(beg==-1)throw new Exception("while parsing "+at_page.toString()+", bad link, missing ′=′ after href: "+s);
int start = beg;
for(;beg<s.length();beg++){
if(s.charAt(beg)==′′′)break;
if(s.charAt(beg)==′"′)break;
}
int end=beg+1;
for(;end<s.length();end++){
if(s.charAt(beg)==s.charAt(end))break;
}
beg++;
if(beg>=end){//missing quotes... just take the first token after "href="
for(beg=start+1;beg<s.length() && (s.charAt(beg)==′ ′);beg++){}
for(end=beg+1;end<s.length() && (s.charAt(beg)!=′ ′) && (s.charAt(beg)!=′>′);end++){}
}
if(beg>=end){
errors.insert("while parsing "+at_page.toString()+", bad href: "+s);
return;
}
String linkto=s.substring(beg,end);
if(linkto.startsWith("mailto:")||linkto.startsWith("Mailto:"))return;
if(linkto.startsWith("javascript:")||linkto.startsWith("javascript:"))return;
if(linkto.startsWith("news:")||linkto.startsWith("javascript:"))return;
try{
addSite(new URL(at_page, linkto));
return;
}catch(Exception e1){}
try{
addSite(new URL(linkto));
return;
}catch(Exception e2){}
try{
addSite(new URL(new URL(at_page.toString()+"/index.html"), linkto));
return;
}catch(Exception e3){}
errors.insert("while parsing "+at_page.toString()+", bad link: "+linkto+", formed from: "+s);
}
/*
* gets the title of a web page with content s
*/
private String getTitle(String s){
try{
int beg=s.indexOf("<title>");
if(beg==-1)beg=s.indexOf("<TITLE>");
int end=s.indexOf("</title>");
if(end==-1)end=s.indexOf("</TITLE>");
return s.substring(beg,end);
}
catch(Exception e){return "";}
}
/*
* gets the text of a web page, times out after 10s
*/
private String getText(URL site) throws Exception
{
urlReader u = new urlReader(site);
Thread t = new Thread(u);
t.setDaemon(true);
t.start();
t.join(TIMEOUT);
String ret = u.poll();
if(ret==null){
throw new Exception("connection timed out");
}else if(ret.equals("Not html")){
throw new Exception("Not an HTML document");
}
return ret;
}
/*
* returns how many sites have been visited so far
*/
public int Visited(){return visitedsites;}
}
class urlReader implements Runnable{
URL site;
String s;
public urlReader(URL u){
site = u;
s=null;
}
public void run(){
try{
String ret=new String();
URLConnection u = site.openConnection();
String type = u.getContentType();
if(type.indexOf("text")==-1 &&
type.indexOf("txt")==-1 &&
type.indexOf("HTM")==-1 &&
type.indexOf("htm")==-1){
//System.err.println("bad content type "+type+" at site "+site);
System.out.println("bad content type "+type+" at site "+site);
ret = "Not html";
return;
}
InputStream in = u.getInputStream();
BufferedInputStream bufIn = new BufferedInputStream(in);
int data;
while(true){
data = bufIn.read();
// Check for EOF
if (data == -1) break;
else ret+= ( (char) data);
}
s = ret;
}catch(Exception e){s=null;}
}
public String poll(){return s;}
}
public class spidergui extends Frame{
private spider s;
private Color txtColor;
private Color errColor;
private Color topColor;
private Color numColor;
private Color curColor;
public spidergui(spider spi, String title){
super(title);
curColor = new Color(40, 40, 200);
txtColor = new Color(0, 0, 0);
errColor = new Color(255, 0, 0);
topColor = new Color(40, 40, 100);
numColor = new Color(50, 150, 50);
s=spi;
setBounds(0, 0, 800, 600);
show();
toFront();
repaint();
}
public void endShow(){
System.out.println(s);
hide();
dispose();
}
public void paint(Graphics g){
super.paint(g);
s.todo.reset();
s.done.reset();
s.errors.reset();
s.omittions.reset();
String txt;
Object o;
g.setColor(curColor);
g.setFont(new Font("arial", Font.PLAIN, 18));
String cur = s.getCurrent();
if(cur.length()>80)g.drawString(
cur.substring(0, 40)+
" . . . "+
cur.substring(cur.length()-30, cur.length()),
50, 50);
else g.drawString(cur, 50, 50);
g.setColor(numColor);
g.setFont(new Font("arial", Font.BOLD, 24));
g.drawString(Integer.toString(s.Visited()), 350, 80);
g.setFont(new Font("arial", Font.PLAIN, 14));
g.setColor(topColor);
g.drawString("To Do:", 100, 80);
g.drawString("Completed:", 500, 80);
g.drawString("Ignored:", 500, 250);
g.drawString("Errors:", 100, 420);
g.setColor(txtColor);
g.setFont(new Font("arial", Font.PLAIN, 12));
for(int i=0;i<23 && (o=s.todo.get())!=null;i++){
txt = Integer.toString(i+1) + ": "+o.toString();
if(txt.length()>65)g.drawString(
txt.substring(0, 38) +
" . . . " +
txt.substring(txt.length()-18, txt.length()),
20, 100+13*i);
else g.drawString(txt, 20, 100+13*i);
}
for(int i=0;i<10 && (o=s.done.get())!=null;i++){
txt = Integer.toString(i+1) + ": "+o.toString();
if(txt.length()>60)g.drawString(txt.substring(0, 57)+"...", 400, 100+13*i);
else g.drawString(txt, 400, 100+13*i);
}
for(int i=0;i<10 && (o=s.omittions.get())!=null;i++){
txt = Integer.toString(i+1) + ": "+o.toString();
if(txt.length()>60)g.drawString(txt.substring(0, 57)+"...", 400, 270+13*i);
else g.drawString(txt, 400, 270+13*i);
}
g.setColor(errColor);
for(int i=0;i<10 && (o=s.errors.get())!=null;i++){
txt = Integer.toString(i+1) + ": "+o.toString();
g.drawString(txt, 20, 440+13*i);
}
}
public void run(){
repaint();
while(s.hasMore()){
repaint();
s.doNextSite();
}
repaint();
}
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3 楼xiao7cn（o(∩_∩)o... 哈哈!）回复于 2006-11-06 17:26:02 得分 0
public static void main(String []args){
int max = 5;
String site="";
String base="";
int time=0;
for(int i=0;i<args.length;i++){
if(args[i].startsWith("-max=")){
max=Integer.parseInt(args[i].substring(5,args[i].length()));
}
else if(args[i].startsWith("-time=")){
time=Integer.parseInt(args[i].substring(6,args[i].length()));
}
else if(args[i].startsWith("-init=")){
site=args[i].substring(6,args[i].length());
}
else if(args[i].startsWith("-base=")){
base=args[i].substring(6,args[i].length());
}
else if(args[i].startsWith("-help")||args[i].startsWith("-?")){
System.out.println("additional command line switches:");
System.out.println("-max=N : to limit to N sites, default 5");
System.out.println("-init=URL : to set the initial site, REQUIRED");
System.out.println("-base=URL : only follow url′s that start with this");
System.out.println(" default "" (matches all URLs)");
System.out.println("-time=N : how many millisec to wait for each page");
System.out.println(" default 5000 (5 seconds)");
System.exit(0);
}
else System.err.println("unrecognized switch: "+args[i]+", continuing");
}
if(site==""){
System.err.println("No initial site parameter!");
System.err.println("Use -init=<site> switch to set, or -help for more info.");
System.exit(1);
}
spider spi=new spider(site, max, base);
if(time>0)spi.setTimer(time);
spidergui s = new spidergui(spi, "Spider: "+site);
s.run();
System.out.println(spi);
}
}Top
4 楼max198231（）回复于 2007-02-02 10:15:51 得分 0
请使用nio
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