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Posted By:   Anonymous
Posted On:   Tuesday, September 25, 2001 10:37 PM

import java.applet.Applet; import java.text.*; import java.awt.*; import java.awt.event.*; import java.util.*; import java.lang.*; import java.net.*; import java.io.*; public class Search extends Applet implements ActionListener, Runnable { public static final String SEARCH = "SEARCH"; //public static final String STOP = "Stop"; public static final String DISALLOW = "Disallow:"; public static final int SEARCH_LIMIT = 50; Panel panelMain; java.awt.List listMatches; Label labelStatus; // URLs to be searched Vector vectorToSearch; // URLs already searched Vector vectorS   More>>

import java.applet.Applet;
import java.text.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.lang.*;
import java.net.*;
import java.io.*;

public class Search extends Applet implements ActionListener, Runnable {
public static final String SEARCH = "SEARCH";
//public static final String STOP = "Stop";
public static final String DISALLOW = "Disallow:";
public static final int SEARCH_LIMIT = 50;

Panel panelMain;
java.awt.List listMatches;
Label labelStatus;

// URLs to be searched
Vector vectorToSearch;
// URLs already searched
Vector vectorSearched;
// URLs which match
Vector vectorMatches;

Thread searchThread;

TextField textURL;
Choice choiceType;

public void init() {

// set up the main UI panel
panelMain = new Panel();
panelMain.setLayout(new BorderLayout(5, 5));

// text entry components
Panel panelEntry = new Panel();
panelEntry.setLayout(new BorderLayout(5, 5));

Panel panelURL = new Panel();
panelURL.setLayout(new FlowLayout(FlowLayout.LEFT, 5, 5));
Label labelURL = new Label("Display: ", Label.RIGHT);
panelURL.add(labelURL);
textURL = new TextField("", 40);
panelURL.add(textURL);
panelEntry.add("North", panelURL);

Panel panelType = new Panel();
panelType.setLayout(new FlowLayout(FlowLayout.LEFT, 5, 5));
/*Label labelType = new Label("Content type: ", Label.RIGHT);
panelType.add(labelType);
choiceType = new Choice();
choiceType.addItem("text/html");
choiceType.addItem("audio/basic");
choiceType.addItem("audio/au");
choiceType.addItem("audio/aiff");
choiceType.addItem("audio/wav");
choiceType.addItem("video/mpeg");
choiceType.addItem("video/x-avi");
panelType.add(choiceType);*/
panelEntry.add("South", panelType);

panelMain.add("North", panelEntry);

// list of result URLs
Panel panelListButtons = new Panel();
panelListButtons.setLayout(new BorderLayout(5, 5));

Panel panelList = new Panel();
panelList.setLayout(new BorderLayout(5, 5));
Label labelResults = new Label("Search results");
panelList.add("North", labelResults);
Panel panelListCurrent = new Panel();
panelListCurrent.setLayout(new BorderLayout(5, 5));
listMatches = new java.awt.List(10);
panelListCurrent.add("North", listMatches);
labelStatus = new Label("");
panelListCurrent.add("South", labelStatus);
panelList.add("South", panelListCurrent);

panelListButtons.add("North", panelList);

// control buttons
Panel panelButtons = new Panel();
Button buttonSearch = new Button(SEARCH);
buttonSearch.addActionListener(this);
panelButtons.add(buttonSearch);
/*Button buttonStop = new Button(STOP);
buttonStop.addActionListener(this);
panelButtons.add(buttonStop);*/

panelListButtons.add("South", panelButtons);

panelMain.add("South", panelListButtons);

add(panelMain);
setVisible(true);

repaint();

// initialize search data structures
vectorToSearch = new Vector();
vectorSearched = new Vector();
vectorMatches = new Vector();

// set default for URL access
URLConnection.setDefaultAllowUserInteraction(false);
}

public void start() {
}

public void stop() {
if (searchThread != null) {
setStatus("stopping...");
searchThread = null;
}
}

public void destroy() {
}

boolean robotSafe(URL url) {
String strHost = url.getHost();

// form URL of the robots.txt file
String strRobot = "/robots.txt";
URL urlRobot;
try {
urlRobot = new URL(strRobot);
} catch (MalformedURLException e) {
// something weird is happening, so don't trust it
return false;
}

String strCommands;
try {
InputStream urlRobotStream = urlRobot.openStream();

// read in entire file
byte b[] = new byte[1000];
int numRead = urlRobotStream.read(b);
strCommands = new String(b, 0, numRead);
while (numRead != -1) {
if (Thread.currentThread() != searchThread)
break;
numRead = urlRobotStream.read(b);
if (numRead != -1) {
String newCommands = new String(b, 0, numRead);
strCommands += newCommands;
}
}
urlRobotStream.close();
} catch (IOException e) {
// if there is no robots.txt file, it is OK to search
return true;
}

// assume that this robots.txt refers to us and
// search for "Disallow:" commands.
String strURL = url.getFile();
int index = 0;
while ((index = strCommands.indexOf(DISALLOW, index)) != -1) {
index += DISALLOW.length();
String strPath = strCommands.substring(index);
StringTokenizer st = new StringTokenizer(strPath);

if (!st.hasMoreTokens())
break;

String strBadPath = st.nextToken();

// if the URL starts with a disallowed path, it is not safe
if (strURL.indexOf(strBadPath) == 0)
return false;
}

return true;
}

public void paint(Graphics g) {
//Draw a Rectangle around the applet's display area.
g.drawRect(0, 0, getSize().width - 1, getSize().height - 1);

panelMain.paint(g);
panelMain.paintComponents(g);
// update(g);
// panelMain.update(g);
}

public void run() {
String strURL = textURL.getText();
String strTargetType = choiceType.getSelectedItem();
int numberSearched = 0;
int numberFound = 0;

if (strURL.length() == 0) {
setStatus("ERROR: must enter a starting URL");
return;
}

// initialize search data structures
vectorToSearch.removeAllElements();
vectorSearched.removeAllElements();
vectorMatches.removeAllElements();
listMatches.removeAll();

vectorToSearch.addElement(strURL);

while ((vectorToSearch.size() > 0)
&& (Thread.currentThread() == searchThread)) {
// get the first element from the to be searched list
strURL = (String) vectorToSearch.elementAt(0);

setStatus("searching" + strURL);

URL url;
try {
url = new URL(strURL);
} catch (MalformedURLException e) {
setStatus("ERROR: invalid URL " + strURL);
break;
}

// mark the URL as searched (we want this one way or the other)
vectorToSearch.removeElementAt(0);
vectorSearched.addElement(strURL);

// can only search http: protocol URLs
if (url.getProtocol().compareTo("http") != 0)
break;

// test to make sure it is before searching
if (!robotSafe(url))
break;

try {
// try opening the URL
URLConnection urlConnection = url.openConnection();

urlConnection.setAllowUserInteraction(false);

InputStream urlStream = url.openStream();
String type
= urlConnection.guessContentTypeFromStream(urlStream);
if (type == null)
break;
if (type.compareTo("text/html") != 0)
break;

// search the input stream for links
// first, read in the entire URL
byte b[] = new byte[1000];
int numRead = urlStream.read(b);
String content = new String(b, 0, numRead);
while (numRead != -1) {
if (Thread.currentThread() != searchThread)
break;
numRead = urlStream.read(b);
if (numRead != -1) {
String newContent = new String(b, 0, numRead);
content += newContent;
}
}
urlStream.close();

if (Thread.currentThread() != searchThread)
break;

String lowerCaseContent = content.toLowerCase();

int index = 0;
while ((index = lowerCaseContent.indexOf("
{
if ((index = lowerCaseContent.indexOf("href", index)) == -1)
break;
if ((index = lowerCaseContent.indexOf("=", index)) == -1)
break;

if (Thread.currentThread() != searchThread)
break;

index++;
String remaining = content.substring(index);

StringTokenizer st
= new StringTokenizer(remaining, "
">#");
String strLink = st.nextToken();

URL urlLink;
try {
urlLink = new URL(url, strLink);
strLink = urlLink.toString();
} catch (MalformedURLException e) {
setStatus("ERROR: bad URL " + strLink);
continue;
}

// only look at http links
if (urlLink.getProtocol().compareTo("http") != 0)
break;

if (Thread.currentThread() != searchThread)
break;

try {
// try opening the URL
URLConnection urlLinkConnection
= urlLink.openConnection();
urlLinkConnection.setAllowUserInteraction(false);
InputStream linkStream = urlLink.openStream();
String strType
= urlLinkConnection.guessContentTypeFromStream(linkStream);
linkStream.close();

// if another page, add to the end of search list
if (strType == null)
break;
if (strType.compareTo("text/html") == 0) {
// check to see if this URL has already been
// searched or is going to be searched
if ((!vectorSearched.contains(strLink))
&& (!vectorToSearch.contains(strLink))) {

// test to make sure it is robot-safe!
if (robotSafe(urlLink))
vectorToSearch.addElement(strLink);
}
}

// if the proper type, add it to the results list
// unless we have already seen it
if (strType.compareTo(strTargetType) == 0) {
if (vectorMatches.contains(strLink) == false) {
listMatches.add(strLink);
vectorMatches.addElement(strLink);
numberFound++;
if (numberFound >= SEARCH_LIMIT)
break;
}
}
} catch (IOException e) {
setStatus("ERROR: couldn't open URL " + strLink);
continue;
}
}
} catch (IOException e) {
setStatus("ERROR: couldn't open URL " + strURL);
break;
}

numberSearched++;
if (numberSearched >= SEARCH_LIMIT)
break;
}

if (numberSearched >= SEARCH_LIMIT || numberFound >= SEARCH_LIMIT)
setStatus("reached search limit of " + SEARCH_LIMIT);
else
setStatus("done");
searchThread = null;
// searchThread.stop();
}

void setStatus(String status) {
labelStatus.setText(status);
}

public void actionPerformed(ActionEvent event) {
String command = event.getActionCommand();

if (command.compareTo(SEARCH) == 0) {
setStatus("searching...");

// launch a thread to do the search
if (searchThread == null) {
searchThread = new Thread(this);
}
searchThread.start();
}
else /*if (command.compareTo(STOP) == 0) {*/
stop();
/*}*/
}
public static void main (String argv[])
{
Frame f = new Frame("SEARCH");
Search applet = new Search();
f.add("Center", applet);

/* Behind a firewall set your proxy and port here!
*/
Properties props= new Properties(System.getProperties());
props.put("http.proxySet", "true");
props.put("http.proxyHost", "webcache-cup");
props.put("http.proxyPort", "8080");

Properties newprops = new Properties(props);
System.setProperties(newprops);
/**/


applet.init();
applet.start();
f.pack();
f.show();
}

}

please see the code and send me the update according to u r convienent. Treat it as urgent please, if u have any further question please mail me:vssai123@rediff.com    <<Less
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