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  • How do I take the advantage of the variable column key/value structure of Cassandra

    - by icejade
    If I have to predefine all the columns, how do I take the advantage of the variable column key/value structure of cassandra? If I use update table command, it will insert null for all the rows which don't have that column. This is same as relational DB. For example, for contact column family, I have name, phone, email. I have 100 contacts have all 3 field. Then number 101 contact has skype id which I want to add. If I use insert statement, it won't let me add skypeid since it's not defined in the CF. So I have to run alter statement to change the CF, then all the first 100 contacts will have a null field for each of them.

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  • overwriting arguments in t-sql functions

    - by chuck taylor
    I was playing around with some code and realized that it is possible to overwrite the argument to a t-sql function. i.e., create function someFn(@date date) as begin if @date is null set @date = getdate() will set @date to be today's date if the argument was null. This appears only to make any sense if t-sql is treating their arguments as references not values. I realized that I don't actually know what the t-sql rules are for cases like this and was hoping someone could elaborate what is going on here. (I don't ever recall seeing any value vs. reference discussion with respect to t-sql code for that matter actually..)

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  • pdo connection scope

    - by Scarface
    Hey guys I have a connection class I found for pdo. I am calling the connection method on the page that the file is included on. The problem is that within functions the $conn variable is not defined even though I stated the method was public (bare with me I am very new to OOP), and I was wondering if anyone had an elegant solution other then using global in every function. Any suggestions are greatly appreciated. CONNECTION class PDOConnectionFactory{ // receives the connection public $con = null; // swich database? public $dbType = "mysql"; // connection parameters // when it will not be necessary leaves blank only with the double quotations marks "" public $host = "localhost"; public $user = "user"; public $senha = "password"; public $db = "database"; // arrow the persistence of the connection public $persistent = false; // new PDOConnectionFactory( true ) <--- persistent connection // new PDOConnectionFactory() <--- no persistent connection public function PDOConnectionFactory( $persistent=false ){ // it verifies the persistence of the connection if( $persistent != false){ $this->persistent = true; } } public function getConnection(){ try{ // it carries through the connection $this->con = new PDO($this->dbType.":host=".$this->host.";dbname=".$this->db, $this->user, $this->senha, array( PDO::ATTR_PERSISTENT => $this->persistent ) ); // carried through successfully, it returns connected return $this->con; // in case that an error occurs, it returns the error; }catch ( PDOException $ex ){ echo "We are currently experiencing technical difficulties. We have a bunch of monkies working really hard to fix the problem. Check back soon: ".$ex->getMessage(); } } // close connection public function Close(){ if( $this->con != null ) $this->con = null; } } PAGE USED ON include("includes/connection.php"); $db = new PDOConnectionFactory(); $conn = $db->getConnection(); function test(){ try{ $sql = 'SELECT * FROM topic'; $stmt = $conn->prepare($sql); $result=$stmt->execute(); } catch(PDOException $e){ echo $e->getMessage(); } } test();

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  • Is it possible to have a variadic function in C with no non-variadic parameter?

    - by Tim
    I have the following function: void doStuff(int unusedParameter, ...) { va_list params; va_start(params, unusedParameter); /* ... */ va_end(params); } As part of a refactor, I'd like to remove the unused parameter without otherwise changing the implementation of the function. As far as I can tell, it's impossible to use va_start when you don't have a last non-variadic parameter to refer to. Is there any way around this? Background: It is in fact a C++ program, so I could use some operator-overloading magic as suggested here, but I was hoping not to have to change the interface at this point. The existing function does its work by requiring that the variable argument list be null-terminated, and scanning for the NULL, therefore it doesn't need a leading argument to tell it how many arguments it has.

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  • Get return values from a stored procedure in c# (login process)

    - by Jin
    Hi all, I am trying to use a Stored Procedure which takes two parameters (login, pw) and returns the user info. If I execute the SP manually, I get Session_UID User_Group_Name Sys_User_Name ------------------------------------ -------------------------------------------------- - NULL Administrators NTMSAdmin No rows affected. (1 row(s) returned) @RETURN_VALUE = 0 Finished running [dbo].[p_SYS_Login]. But with the code below, I only get the return value. do you know how to get the other values shown above like Session_UID, User_Group_Name, and Sys_User_Name ? if you see the commented part below code. I tried to add some output parameters but it doesn't work with incorrect number of parameters error. string strConnection = Settings.Default.ConnectionString; using (SqlConnection conn = new SqlConnection(strConnection)) { using (SqlCommand cmd = new SqlCommand()) { SqlDataReader rdr = null; cmd.Connection = conn; cmd.CommandText = "p_SYS_Login"; //cmd.CommandText = "p_sys_Select_User_Group"; cmd.CommandType = CommandType.StoredProcedure; SqlParameter paramReturnValue = new SqlParameter(); paramReturnValue.ParameterName = "@RETURN_VALUE"; paramReturnValue.SqlDbType = SqlDbType.Int; paramReturnValue.SourceColumn = null; paramReturnValue.Direction = ParameterDirection.ReturnValue; //SqlParameter paramGroupName = new SqlParameter("@User_Group_Name", SqlDbType.VarChar, 50); //paramGroupName.Direction = ParameterDirection.Output; //SqlParameter paramUserName = new SqlParameter("@Sys_User_Name", SqlDbType.VarChar, 50); //paramUserName.Direction = ParameterDirection.Output; cmd.Parameters.Add(paramReturnValue); //cmd.Parameters.Add(paramGroupName); //cmd.Parameters.Add(paramUserName); cmd.Parameters.AddWithValue("@Sys_Login", textUserID.Text); cmd.Parameters.AddWithValue("@Sys_Password", textPassword.Text); try { conn.Open(); object result = cmd.ExecuteNonQuery(); int returnValue = (int)cmd.Parameters["@RETURN_VALUE"].Value; if (returnValue == 0) { Hide(); Program.MapForm.Show(); } else if (returnValue == 1) { MessageBox.Show("The username or password you entered is incorrect", "NTMS Login", MessageBoxButtons.OK, MessageBoxIcon.Warning); } else if (returnValue == 2) { MessageBox.Show("This account is disabled", "NTMS Login", MessageBoxButtons.OK, MessageBoxIcon.Warning); } else { MessageBox.Show("Database error. Please contact administrator", "NTMS Login", MessageBoxButtons.OK, MessageBoxIcon.Warning); } } catch (Exception ex) { string message = ex.Message; string caption = "MAVIS Exception"; MessageBoxButtons buttons = MessageBoxButtons.OK; MessageBox.Show( message, caption, buttons, MessageBoxIcon.Warning, MessageBoxDefaultButton.Button1); } } } Thanks for your help.

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  • Left outer joins that don't return all the rows from T1

    - by Summer
    Left outer joins should return at least one row from the T1 table if it matches the conditions. But what if the left outer join performs a join successfully, then finds that another criterion is not satisfied? Is there a way to get the query to return a row with T1 values and T2 values set to NULL? Here's the specific query, in which I'm trying to return a list of candidates, and the user's support for those candidates IF such support exists. SELECT c.id, c.name, s.support FROM candidates c LEFT JOIN support s on s.candidate_id = c.id WHERE c.office_id = 5059 AND c.election_id = 92 AND (s.user_id = 2 OR s.user_id IS NULL) --This line seems like the problem ORDER BY c.last_name, c.name The query joins the candidates and support table, but finds that it's a different user who supported this candidate (user_id=3, say). Then the candidate disappears entirely from the result set.

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  • How could my code compliled correctly without necessary headers?

    - by ZhengZhiren
    I use the functions fork(),exec()... But how can this program compiled without including some extra headers(like sys/types.h, sys/wait.h). I use ubuntu 10.04 with gcc version 4.4.3 #include <stdio.h> #include <stdlib.h> int main() { pid_t pid; printf("before fork\n"); pid = fork(); if(pid == 0) { /*child*/ if(execvp("./cpuid", NULL)) { printf("error\n"); exit(0); } } else { if(wait(NULL) != -1) { printf("ok\n"); } } return 0; }

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  • Linked List Inserting in sorted format

    - by user2738718
    package practise; public class Node { public int data; public Node next; public Node (int data, Node next) { this.data = data; this.next = next; } public int size (Node list) { int count = 0; while(list != null){ list = list.next; count++; } return count; } public static Node insert(Node head, int value) { Node T; if (head == null || head.data <= value) { T = new Node(value,head); return T; } else { head.next = insert(head.next, value); return head; } } } This work fine for all data values less than the first or the head. anything greater than than doesn't get added to the list.please explain in simple terms thanks.

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  • jQuery Swap Image on Click and if/else

    - by jrutter
    Im stuck, Im setting a variable when someone clicks, then testing with if to see if the variable exists and doing something else. Its a simple script which Im probably overthinking, would love someone's thoughts. $('.view-alternatives-btn').live('click', function() { //$("#nc-alternate-wines").scrollTo(); //$('.nc-remove').toggle(); var showBtn = null; if (showBtn == null) { $('.view-alternatives-btn img').attr("src","../images/wsj_hide_alternatives_btn.gif"); $('#nc-alternate-wines').show(); showBtn = 1; console.log(showBtn); } else if (showBtn == 1) { $('.view-alternatives-btn img').attr("src","../images/wsj_view_alternatives_btn.gif"); $('#nc-alternate-wines').hide(); console.log("this " + showBtn); } return false; });

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  • Apply CSS class to invalid controls on web form

    - by user137639
    I need to apply a css class to invalid controls on a web form. I'd like to make it a resusable class. This is what I have so far: public class Validation { public static void ApplyInvalidClass(Page page, string className) { foreach (System.Web.UI.WebControls.BaseValidator bv in page.Validators) { if (!bv.IsValid) { Control ctrl = page.FindControl(bv.ControlToValidate); if (ctrl != null) { if (ctrl is TextBox) { TextBox txt = ctrl as TextBox; txt.CssClass = "invalid"; } if (ctrl is DropDownList) { DropDownList ddl = ctrl as DropDownList; ddl.CssClass = "invalid"; } if (ctrl is CheckBox) { CheckBox cb = ctrl as CheckBox; cb.CssClass = "invalid"; } if (ctrl is HtmlGenericControl) { HtmlGenericControl html = ctrl as HtmlGenericControl; html.Attributes.Add("class", className); } } } } } } The problem is what I call this on a .Net user control, I guess because I'm passing in Page, page.FindControl(bv.ControlToValidate) is always null. Is there a better way to do this?

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  • how to interpret testng console log message for passing tests?

    - by Kunal Cholera
    I ran testng tests for my test classes, I get the following three types of log output when I run the passing tests. I am using org.testng.AssertJUnit.assertTrue() methods in my tests. [testng] PASSED: testMethod1 on null(test.foo.bar.Class1) [testng] PASSED: testMethod2 on Default test name(test.foo.bar.jar.Class2) [testng] PASSED: testMethod3 Can any one please tell me why for some tests it says "on null" for some it says "on Default test name ... " and for some it does not say anything on the console output. Specifically I want to make it consistent message. Environment : linux Testng framework : 6.3.2beta please advise. thanks.

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  • Deselecting an element in jQuery

    - by Michael Itzoe
    I have a collection of span elements. In the code I have a global variable that represents the "selected" object. Using the click event when a span is clicked I reset the object's class, reset the global variable, then set the object to the variable and change its class (to make it "highlighted"). This effectively toggles selection when clicking an object. var currentItem = null; $( ".item" ).click( function() { if( $( this ).hasClass( "selected" ) ) { $( this ).removeClass( "selected" ) currentItem = null; } else { if( $( ".item" ).hasClass( "selected" ) ){ $( ".item" ).removeClass( "selected" ) } $( this ).addClass( "selected" ); currentItem = $( this ); } } ); What I'd like to be able to do is unselect when clicking on an empty area of the page. I tried creating a click event on the body object, but that overrode the span click event so nothing was selected. I'm a complete jQuery noob and not sure where to go with this.

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  • Which is the 'correct' way to do this (if statement)

    - by frinkz
    I've got plenty of these lying around, and I'm wondering if I'm going to face any trouble - or performance problems. I have method A: MyClass monkey; ... if(monkey != null) { ... } Or method B: boolean hasMonkey; //This is set to TRUE when monkey is not null MyClass monkey; ... if(hasMonkey) { ... } On a functional level, they both do the same thing. Right now, I'm using method A. Is that a bad way of doing things? Which is going to perform better?

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  • inheritance from the django user model results in error when changing password

    - by Jerome
    I inherited form the django user model like so: from django.db import models from django.contrib.auth.models import User, UserManager from django.utils.translation import ugettext_lazy as _ class NewUserModel(User): custom_field_1 = models.CharField(_('custom field 1'), max_length=250, null=True, blank=True) custom_field_2 = models.CharField(_('custom field 2'), max_length=250, null=True, blank=True) objects = UserManager() When i go to the admin and add an entry into this model, it saves fine, but below the "Password" field where it has this text "Use '[algo]$[salt]$[hexdigest]' or use the change password form.", if i click on the "change password form' link, it produces this error Truncated incorrect DOUBLE value: '7/password' What can i do to fix this?

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  • Adding a new power scheme to Windows Server 2008 R2

    - by user296933
    I am trying to add a new power scheme to Windows Server 2008 R2. However, the new power scheme has the same settings as the current one. What am I doing something wrong? PGLOBAL_POWER_POLICY globalPolicy = new GLOBAL_POWER_POLICY(); PPOWER_POLICY powerPolicy = new POWER_POLICY(); printf("Idle sensitivity: %d\n", powerPolicy->user.IdleSensitivityAc); GetCurrentPowerPolicies(globalPolicy, powerPolicy); powerPolicy->user.IdleSensitivityAc = 100; PUINT pwrScheme = new UINT(); *pwrScheme = 10; WritePwrScheme(pwrScheme,(LPCWSTR)"MyScheme",(LPCWSTR)"MyScheme", powerPolicy); SetActivePwrScheme(pwrScheme,NULL,NULL); GetCurrentPowerPolicies(globalPolicy, powerPolicy); printf("Idle sensitivity: %d\n", powerPolicy->user.IdleSensitivityAc);

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  • AudioTrack skipping after pause and resume

    - by Markus Drösser
    Hi, here is the problem. I play a wav file that i recorded earlier without problems. but when i call audiotrack.pause() and audiotrack.start() again after some waiting, it skips some frames of the file. why is that? here is my play listener // Start playback audioTrack.setPlaybackPositionUpdateListener(new OnPlaybackPositionUpdateListener() { @Override public void onPeriodicNotification(AudioTrack track) { try { if(ramfile!=null && ramfile.read(buffer)==-1) { audioTrack.release(); audioTrack = null; ramfile.close(); playing=false; } else { audioTrack.write(buffer, 0, buffer.length); } } catch (IOException e) { try { ramfile.close(); playing=false; } catch (IOException e1) { } } } @Override public void onMarkerReached(AudioTrack track) { playing=false; track.release(); } });

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  • Are conditional subqueries optimized out, if the condition is false?

    - by Tobias Schulte
    I have a table foo and a table bar, where each foo might have a bar (and a bar might belong to multiple foos). Now I need to select all foos with a bar. My sql looks like this SELECT * FROM foo f WHERE [...] AND ($param IS NULL OR (SELECT ((COUNT(*))>0) FROM bar b WHERE f.bar = b.id)) with $param being replaced at runtime. The question is: Will the subquery be executed even if param is null, or will the dbms optimize the subquery out? We are using mysql, mssql and oracle. Is there a difference between these regarding the above?

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  • Should I 'delete' this CDC?

    - by Binary Worrier
    Folks, I'm trying to track down an intermittant bug that's showing up on site. I've a feeling it's in some GDI code I'd to cobble together to get a tally printer working. I'm connfused over how to delete this CDC, my code looks OK to me, but is this correct. // Create a device context for printing CDC* dc = new CDC(); if(! dc->CreateDC(safeDriverName.AsBSTR(), safePrinterName.AsBSTR(), NULL, NULL)) { throw . . . } // as I finish with the CDC dc->DeleteDC(); delete dc; Do I need delete dc after dc->DeleteDC();? Thanks

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  • Obtaining kerning information

    - by chadb
    How can I obtain kerning information for GDI to then use in GetKerningPairs? The documentation states that The number of pairs in the lpkrnpair array. If the font has more than nNumPairs kerning pairs, the function returns an error. However, I do not know how many pairs to pass in, and I don't see a way to query for it. EDIT I tried to do the following, however, it still gave me 0. Font* myFont = new Font(L"Times New Roman", 10); Bitmap* bitmap = new Bitmap(256, 256, PixelFormat32bppARGB); Graphics* g = new Graphics(bitmap); SelectObject(g->GetHDC(), myFont); //DWORD numberOfKerningPairs = GetKerningPairs( g->GetHDC(), -1, NULL ); DWORD numberOfKerningPairs = GetKerningPairs( g->GetHDC(), INT_MAX, NULL );

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  • How does lock(syncRoot) make sense on a static method?

    - by Rising Star
    The following code is excerpted from the (Windows Identity Foundation SDK) template that MS uses to create a new Security Token Service Web Site. public static CustomSecurityTokenServiceConfiguration Current { get { HttpApplicationState httpAppState = HttpContext.Current.Application; CustomSecurityTokenServiceConfiguration customConfiguration = httpAppState.Get( CustomSecurityTokenServiceConfigurationKey ) as CustomSecurityTokenServiceConfiguration; if ( customConfiguration == null ) { lock ( syncRoot ) { customConfiguration = httpAppState.Get( CustomSecurityTokenServiceConfigurationKey ) as CustomSecurityTokenServiceConfiguration; if ( customConfiguration == null ) { customConfiguration = new CustomSecurityTokenServiceConfiguration(); httpAppState.Add( CustomSecurityTokenServiceConfigurationKey, customConfiguration ); } } } return customConfiguration; } } I'm relatively new to multi-threaded programming. I assume that the reason for the lock statement is to make this code thread-safe in the event that two web requests arrive at the web site at the same time. However, I would have thought that using lock (syncRoot) would not make sense because syncRoot refers to the current instance that this method is operating on... but this is a static method? How does this make sense?

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  • INSERT SQL in Java

    - by Pierre
    Hello. I have a Java application and I want to use SQL database. I have a class for my connection : public class SQLConnection{ private static String url = "jdbc:postgresql://localhost:5432/table"; private static String user = "postgres"; private static String passwd = "toto"; private static Connection connect; public static Connection getInstance(){ if(connect == null){ try { connect = DriverManager.getConnection(url, user, passwd); } catch (SQLException e) { JOptionPane.showMessageDialog(null, e.getMessage(), "Connection Error", JOptionPane.ERROR_MESSAGE); } } return connect; } } And now, in another class I succeeded to print my values but when I attempt to insert a value nothing is happening ... Here's my code : try { Statement state = SQLConnection.getInstance().createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY); Statement state2 = SQLConnection.getInstance().createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_UPDATABLE); state2.executeUpdate("INSERT INTO table(field1) VALUES (\"Value\")"); // Here's my problem ResultSet res = state.executeQuery("SELECT * FROM plateau");

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  • How to ReHash a password stored into my Database ? (PHP)

    - by Vincent Roye
    Hi! I have some passwords encrypted in my database and I would like to find a way to display them. Here is how they are saved into my mysql database: function generateHash($plainText, $salt = null){ if ($salt === null) { $salt = substr(md5(uniqid(rand(), true)), 0, 25); } else { $salt = substr($salt, 0, 25); } return $salt . sha1($salt . $plainText); } $secure_pass = generateHash($this->clean_password); Then $secure_pass is saved into my database. Anyone would have an idea ?? Thank you very much ;)

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  • How can I obtain the IP address of my server program?

    - by Dr Dork
    Hello! This question is related to another question I just posted. I'm prepping for a simple work project and am trying to familiarize myself with the basics of socket programming in a Unix dev environment. At this point, I have some basic server side code and client side code setup to communicate. Currently, my client code successfully connects to the server code and the server code sends it a test message, then both quit out. Perfect! That's exactly what I wanted to accomplish. Now I'm playing around with the functions used to obtain info about the two environments (server and client). I'd like to obtain my server program's IP address. Here's the code I currently have to do this, but it's not working... int sockfd; unsigned int len; socklen_t sin_size; char msg[]="test message"; char buf[MAXLEN]; int st, rv; struct addrinfo hints, *serverinfo, *p; struct sockaddr_storage client; char s[INET6_ADDRSTRLEN]; char ip[INET6_ADDRSTRLEN]; //zero struct memset(&hints,0,sizeof(hints)); hints.ai_family = AF_UNSPEC; hints.ai_socktype = SOCK_STREAM; hints.ai_flags = AI_PASSIVE; //get the server info if((rv = getaddrinfo(NULL, SERVERPORT, &hints, &serverinfo ) != 0)){ perror("getaddrinfo"); exit(-1); } // loop through all the results and bind to the first we can for( p = serverinfo; p != NULL; p = p->ai_next) { //Setup the socket if( (sockfd = socket( p->ai_family, p->ai_socktype, p->ai_protocol )) == -1 ) { perror("socket"); continue; } //Associate a socket id with an address to which other processes can connect if(bind(sockfd, p->ai_addr, p->ai_addrlen) == -1){ close(sockfd); perror("bind"); continue; } break; } if( p == NULL ){ perror("Fail to bind"); } inet_ntop(p->ai_family, get_in_addr((struct sockaddr *)p->ai_addr), s, sizeof(s)); printf("Server has TCP Port %s and IP Address %s\n", SERVERPORT, s); and the output for the IP is always empty... server has TCP Port 21412 and IP Address :: any ideas for what I'm missing? thanks in advance for your help! this stuff is really complicated at first.

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  • Retrieve KEYWORDS from META tag in a HTML WebPage using JAVA.

    - by kooldave98
    Hello all, I want to retrieve all the content words from a HTML WebPage and all the keywords contained in the META TAG of the same HTML webpage using Java. For example, consider this html source code: <html> <head> <meta name = "keywords" content = "deception, intricacy, treachery"> </head> <body> My very short html document. <br> It has just 2 'lines'. </body> </html> The CONTENT WORDS here are: my, very, short, html, document, it, has, just, lines Note: The punctuation and the number '2' are ruled out. The KEYWORDS here are: deception, intricacy, treachery I have created a class for this purpose called WebDoc, this is as far as I have been able to get. import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.net.URL; import java.util.Set; import java.util.TreeSet; public class WebDoc { protected URL _url; protected Set<String> _contentWords; protected Set<String> _keyWords public WebDoc(URL paramURL) { _url = paramURL; } public Set<String> getContents() throws IOException { //URL url = new URL(url); Set<String> contentWords = new TreeSet<String>(); BufferedReader in = new BufferedReader(new InputStreamReader(_url.openStream())); String inputLine; while ((inputLine = in.readLine()) != null) { // Process each line. contentWords.add(RemoveTag(inputLine)); //System.out.println(RemoveTag(inputLine)); } in.close(); System.out.println(contentWords); _contentWords = contentWords; return contentWords; } public String RemoveTag(String html) { html = html.replaceAll("\\<.*?>",""); html = html.replaceAll("&",""); return html; } public Set<String> getKeywords() { //NO IDEA ! return null; } public URL getURL() { return _url; } @Override public String toString() { return null; } }

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