Search Results

Search found 44026 results on 1762 pages for 'raid question'.

Page 110/1762 | < Previous Page | 106 107 108 109 110 111 112 113 114 115 116 117  | Next Page >

  • question about book example - Java Concurrency in Practice, Listing 4.12

    - by mike
    Hi, I am working through an example in Java Concurrency in Practice and am not understanding why a concurrent-safe container is necessary in the following code. I'm not seeing how the container "locations" 's state could be modified after construction; so since it is published through an 'unmodifiableMap' wrapper, it appears to me that an ordinary HashMap would suffice. EG, it is accessed concurrently, but the state of the map is only accessed by readers, no writers. The value fields in the map are syncronized via delegation to the 'SafePoint' class, so while the points are mutable, the keys for the hash, and their associated values (references to SafePoint instances) in the map never change. I think my confusion is based on what precisely the state of the collection is in the problem. Thanks!! -Mike Listing 4.12, Java Concurrency in Practice, (this listing available as .java here, and also in chapter form via google) /////////////begin code @ThreadSafe public class PublishingVehicleTracker { private final Map<String, SafePoint> locations; private final Map<String, SafePoint> unmodifiableMap; public PublishingVehicleTracker( Map<String, SafePoint> locations) { this.locations = new ConcurrentHashMap<String, SafePoint>(locations); this.unmodifiableMap = Collections.unmodifiableMap(this.locations); } public Map<String, SafePoint> getLocations() { return unmodifiableMap; } public SafePoint getLocation(String id) { return locations.get(id); } public void setLocation(String id, int x, int y) { if (!locations.containsKey(id)) throw new IllegalArgumentException( "invalid vehicle name: " + id); locations.get(id).set(x, y); } } // monitor protected helper-class @ThreadSafe public class SafePoint { @GuardedBy("this") private int x, y; private SafePoint(int[] a) { this(a[0], a[1]); } public SafePoint(SafePoint p) { this(p.get()); } public SafePoint(int x, int y) { this.x = x; this.y = y; } public synchronized int[] get() { return new int[] { x, y }; } public synchronized void set(int x, int y) { this.x = x; this.y = y; } } ///////////end code

    Read the article

  • XML structure question

    - by Andrew Jahn
    I have a basic XML object that I'm working with. I can't figure out how to access the parts of it. EX:<br> <pre><code> < FacetsData> < Collection name="CDDLALL" type="Group"> < SubCollection name="CDDLALL" type="Row"> < Column name="DPDP_ID">D0230< /Column> < Column name="Count">9< /Column> < /SubCollection> < SubCollection name="CDDLALL" type="Row"> < Column name="DPDP_ID">D1110< /Column> < Column name="Count">9< /Column> < /SubCollection> < /Collection> < /FacetsData> (PS: I can't get this damn xml to format so people can read it) What I need to do is check each DPDP_ID and if its value is D0230 then I leave the Count alone, all else I change the Count to 1. What I have so far: node = doc.DocumentElement; nodeList = node.SelectNodes("/FacetsData/Collection/SubCollection"); for (int x = 0; x < nodeList.Count; x++) { if (nodeList[x].HasChildNodes) { for (int i = 0; i < nodeList[x].ChildNodes.Count; i++) { //This part I can't figure out how to get the name="" part of the xml //MessageBox.Show(oNodeList[x].ChildNodes[i].InnerText); get the "D0230","1" //part but not the "DPDP_ID","Count" part. } } }

    Read the article

  • PowerShell question

    - by Ybbest
    Hey I got the following ps for retrieving the site template from SharePoint,but I do not quite undersantd what does the second half of the script( | ? {$_.IsHidden -eq $false }) does? Can someone explain this to me please as I am fairly new to PS. Get-SPWebTemplate | ? {$_.IsHidden -eq $false }

    Read the article

  • question about polynomial multiplication

    - by davit-datuashvili
    i know that horners method for polynomial pultiplication is faster but here i dont know what is happening here is code public class horner{ public static final int n=10; public static final int x=7; public static void main(String[] args){ //non fast version int a[]=new int[]{1,2,3,4,5,6,7,8,9,10}; int xi=1; int y=a[0]; for (int i=1;i<n;i++){ xi=x*xi; y=y+a[i]*xi; } System.out.println(y); //fast method int y1=a[n-1]; for (int i=n-2;i>=0;i--){ y1=x*y+a[i]; } System.out.println(y1); } } result of this two methods are not same result of first method is 462945547 and result of second method is -1054348465 please help

    Read the article

  • Validation L2S question

    - by user158020
    This may be a bit winded because I am new to wpf. I have created a partial class for an entity in my L2S class that is primarily used for validation. It implements the onchanging and onvalidate methods. I am trying to use the MVVM pattern, and in a window/view I have set the datacontext in the xaml: <Window.DataContext> <vm:StartViewModel /> </Window.DataContext> when a user leaves a required field in the view blank, the onchanging event of the partial class is fired when I close the form, not when I save the data. So, if a user leaves the textbox blank, the old value is retained and the onchaging method is fired, but I have no idea how to alert the user of the resulting error. here is my onchanging code in the partial class: partial void Ondocument_titleChanging(string value) { if (value.Length == 0) throw new Exception("Document title is required."); if (value.Length > 256) throw new Exception("Document title cannot be longer than 256 characters."); } throwing an exception doesn't notify the user of the error. it just allows the form to close and rejects the changes to the textbox. hope this makes sense... edit: this example was taken from Scott Guthries article here: http://aspalliance.com/1427_LINQ_to_SQL_Part_5__Binding_UI_using_the_ASPLinqDataSource_Control.5

    Read the article

  • C++ Beginner Delete Question

    - by Pooch
    Hi all, This is my first year learning C++ so bear with me. I am attempting to dynamically allocate memory to the heap and then delete the allocated memory. Below is the code that is giving me a hard time: // String.cpp #include "String.h" String::String() {} String::String(char* source) { this->Size = this->GetSize(source); this->CharArray = new char[this->Size + 1]; int i = 0; for (; i < this->Size; i++) this->CharArray[i] = source[i]; this->CharArray[i] = '\0'; } int String::GetSize(const char * source) { int i = 0; for (; source[i] != '\0'; i++); return i; } String::~String() { delete[] this->CharArray; } Here is the error I get when the compiler tries to delete the CharArray: 0xC0000005: Access violation reading location 0xccccccc0. And here is the last call on the stack: msvcr100d.dll!operator delete(void * pUserData) Line 52 + 0x3 bytes C++ I am fairly certain the error exists within this piece of code but will provide you with any other information needed. Oh yeah, using VS 2010 for XP. Thanks for any and all help!

    Read the article

  • Spring URL mapping question

    - by es11
    I am using Java with Spring framework. Given the following url: www.mydomain.com/contentitem/234 I need to map all requests that come to /contentitem/{numeric value} mapped to a given controller with the "numeric value" passed as a parameter to the controller. Right now in my servlet container xml I have simple mappings similar to the following: ... <entry key="/index.html"> <ref bean="homeController" /> </entry> ... I am just wondering what I need to add to the mapping in order to achieve what I described? Edit: I unaccepted the answer temporarily because I can't seem to figure out how to do the mapping in my web.xml (I am using annotations as described in axtavt's answer below). How do I add a proper <url-pattern>..</url-pattern> in my <servlet-mapping> so that the request for "/contentitem/{numeric_value}" gets properly picked up? Thanks!

    Read the article

  • mvc contrib pager question - AsPagination

    - by csetzkorn
    Hi, I might be wrong but is the AsPagination method not very inefficient as it sucks all the data from a repository first to initialise TotalItems etc.? So paging is not used to make the data access more efficient. I have not found any examples which use a repository and 'true' paging (i.e. uses TOP etc. in the atcual SQL). How do I use the Pager if I have a repository method with this signature: IList GetData(int? page, out int TotalItems) Any feedback would be very much appreciated. Thanks. Christian

    Read the article

  • sql query question / count

    - by scheibenkleister
    Hi, I have houses that belongs to streets. A user can buy several houses. How do I find out, if the user owns an entire street? street table with columns (id/name) house table with columns (id/street_id [foreign key] owner table with columns (id/house_id/user_id) [join table with foreign keys] So far, I'm using count which returns the result: select count(*), street_id from owner left join house on owner.house_id = house.id group by street_id where user_id = 1 count(*) | street_id 3 | 1 2 | 2 A more general count: select count(*) from house group by street_id returns: count(*) | street_id 3 | 1 3 | 2 How can I find out, that user 1 owns the entire street 1 but not street 2? Thanks.

    Read the article

  • jQuery attribute question

    - by Nick Simone
    I'm trying to select a series of divs one at a time. I'm sure theres a better way to do this, but I gave them all unique rels and I'm using the rels to select them one at a time. I want to move them over the width of the div, then animate it dropping down the screen. What I have is: $(document).ready(function(){ var totalbricks = 7; var index = 2; $(".brick").animate({top:"600px"}); while(index < totalbricks) { var postion = 45*index; $(".brick[rel='+index+']").css('left', postion+'px'); $(".brick[rel='+index+']").animate({top:"600px"}); index++; } }); All the divs are in a container div. Jquery docs say, 'Variables can be used using the following syntax: [name='" +MyVar+ "']' What am I doing wrong? Here is the HTML that is being used by the jQuery <body> <div id="container"> <div id="canvas"> <div class="brick" rel="1"> </div> <div class="brick" rel="2"> </div> <div class="brick" rel="3"> </div> <div class="brick" rel="4"> </div> <div class="brick" rel="5"> </div> <div class="brick" rel="6"> </div> <div class="brick" rel="7"> </div> </div> </div> </body>

    Read the article

  • Question about Architecture for Viewing Images in ASP.NET MVC App

    - by Charlie Flowers
    I have an approach in mind for an image viewer in a web app, and want to get a sanity check and any thoughts you stackoverflowers might have. Here's the whirlwind nutshell summary: I'm working on an ASP.NET MVC application that will run in my company's retail stores. Even though it is a web application, we own the store machines and have control over them. We have a "windows agent" running on the store machine which we can talk to from the browser via javascript (it is a WCF service, and our web app has permission to talk to it from the browser). One of the web pages needs to be an "image viewer" page with some common things like Rotate & Zoom. Now, there are some WebForms controls that offer Rotate and Zoom. However, they take up server resources and generate a good bit of traffic between the server and the browser. For example, the Rotate function would cause an ajax call to the server, which would then generate a new image written to a .NET Canvas object, which would then be written to a file on the server, which would then be returned from the ajax call and refreshed inside the browser. Normally, that's a pretty good way of doing things. But in our case, we have code running on the store machine that we can communicate with. This leads me to consider the following approach: When the user asks to view an image, we tell our "windows agent" to download it from our image server to the store machine. We then redirect our browser to our image viewer page, which will pull the image from the local file we just wrote to the store machine. When the user clicks "Rotate", we cause JavaScript code in the browser to call our "windows agent" software, asking it to perform the "Rotate" function. The "windows agent" does the rotation using the same kind of imaging control that would formerly have been used on the server, but it does so now on the store machine. Javascript in the browser then refreshes the image on the page to show the newly rotated image. Zoom and similar features would be implemented the same way. This seems to be much more efficient, scalable, and responsive for the end-users. However, I've never heard of anything like it being done, mostly because it's rare to have this combination of a web app plus a "windows agent" on the client machine. What do you think? Feasible? Reasonable? Any pitfalls I overlooked or improvements / suggestions you can see? Has anyone done anything like this who would like to offer the wisdom of experience? Thanks!

    Read the article

  • Recursion Question : Revision

    - by stan
    My slides say that: A recursive call should always be on a smaller data structure than the current one There must be a non recursive option if the data structure is too small You need a wrapper method to make the recursive method accessible Just reading this from the slides makes no sense, especially seeing as it was a topic from before christmas! Could anyone try and clear up what it means please? Thank you

    Read the article

  • Question about [Pure] methods

    - by devoured elysium
    Is the following method Pure? I'd say so, as it doesn't change in anyway the current class, thus, everything we can now currenly "see" in the class, before running this method will still be exactly the same after. Am I correct? class Set { ... public ISet<T> UnionWith(ISet<T> set) { ISet<T> unionSet = ... foreach (Element element in this) { unionSet.Add(element); } foreach (Element element in set) { unionSet.Add(element); } return unionSet; } }

    Read the article

  • C# Winform Question

    - by Soo
    Hi SO, I'm just getting started with winforms in C# and things are going well, except I want to learn how to do something like: if user presses "proceed" button, it will run some code, and change the form, so that there are more options available to the user on the form. In other words, I want to make my forms more than one "page". I hope that all makes sense. Any help would be appreciated, thanks!

    Read the article

  • summer experiment: GWT & python for a trading game- arch question

    - by sadhu_
    Hi, As a summer learning experiment, I'm thinking of coding up a web front end for a trading game i wrote in python, that generates share prices and random snippets of text. I am sort of struggling with how this should work on the back-end though. I'd rather have my GWT client page interact with the python share price generator, than to try and re-code it in java. I suppose i could use an sqlite db, and then use jdbc to pick up the prices, but i was wondering if there is a better way, for me to be able to poll some python script either from my client page, or from the serverside java code ? I found this python wrapper, but i'm not sure how i could use it though: http://code.google.com/apis/visualization/documentation/dev/gviz_api_lib.html Thanks.

    Read the article

  • programming question

    - by shivam
    using System; using System.Data; using System.Collections.Generic; using System.ComponentModel; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using System.Data.SqlClient; namespace datasynchronization { public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void button1_Click(object sender, EventArgs e) { string connectString = @"Data Source=MOON\SQL2005;Initial Catalog=databaseA;Integrated Security=True"; using (var srcCon = new SqlConnection(connectString)) //connection to source table { srcCon.Open();//source table connection open SqlCommand cmd = new SqlCommand();// sqlobject for source table cmd.Connection = srcCon; string connectionString = @"Data Source=MOON\SQL2005;Initial Catalog=databaseB;Integrated Security=True"; using (var tgtCon = new SqlConnection(connectionString)) //connection to target table { tgtCon.Open(); //target table connection open SqlCommand objcmd1 = new SqlCommand();//sqlobject for target table objcmd1.Connection = tgtCon; objcmd1.CommandText = "SELECT MAX(date) FROM Table_2"; //query to findout the max date from target table var maxdate = objcmd1.ExecuteScalar(); // store the value of max date into the variable maxdate cmd.CommandText = string.Format("SELECT id,date,name,city,salary,region FROM Table_1 where date >'{0}'", maxdate); //select query to fetch rows from source table using (var reader = cmd.ExecuteReader()) { SqlCommand objcmd = new SqlCommand(); objcmd.Connection = tgtCon; objcmd.CommandText = "INSERT INTO Table_2(id,date,name,city,salary,region)VALUES(@id,@date,@name,@city,@salary,@region)"; objcmd.Parameters.Add("@id", SqlDbType.Int); objcmd.Parameters.Add("@date", SqlDbType.DateTime); objcmd.Parameters.Add("@name", SqlDbType.NVarChar); objcmd.Parameters.Add("@city", SqlDbType.NVarChar); objcmd.Parameters.Add("@salary", SqlDbType.Int); objcmd.Parameters.Add("@region", SqlDbType.Char); while (reader.Read()) { var order1 = reader[0].ToString(); var order2 = reader[1].ToString(); var order3 = reader[2].ToString(); var order4 = reader[3].ToString(); var order5 = reader[4].ToString(); var order6 = reader[5].ToString(); objcmd.Parameters["@id"].Value = order1; objcmd.Parameters["@date"].Value = order2; objcmd.Parameters["@name"].Value = order3; objcmd.Parameters["@city"].Value = order4; objcmd.Parameters["@salary"].Value = order5; objcmd.Parameters["@region"].Value = order6; objcmd.ExecuteNonQuery(); } } tgtCon.Close(); } srcCon.Close(); } } } } how can i organize the above written code in an efficient way?

    Read the article

  • Question about A Sketching Website on the IPAD, Dragging and Touching

    - by pfunc
    I've been testing out the new functionality of html5 and js to create a sketching site. I've been looking into this for a possible client that wants their site to be ipad accessible, but also have drawing features on it. So i created a rough experiment where you can drag your mouse across a screen to draw lines. I went to test it on an ipad and realized this doesn't work. Why? because dragging on an ipad is reserved for actually dragging the screen around. Is there something you can do to get around this? I'm sure this could be done if made for an app, but what about just a normal website.

    Read the article

  • Flex 4 animation question

    - by Jerry
    Hello.. I am trying to do the move vertically animation on a button nested in the vertical layout. I am not sure if the Hgroup restricts the button moving vertically. Are there ways to go around it? Thanks for the helps. <s:states> <s:State name="default"/> <s:State name="addRecommend"/> <s:State name="seeOther"/> </s:states> AS: protected function add_clickHandler(event:MouseEvent):void { currentState="addRecommend"; addRecommendMove.play(); } <s:transitions> <s:Transition fromState="default" toState="addRecommend"> <s:Sequence id="addRecommendMove"> <s:Move yTo="50" target="{add}"/> // add button doesn't move at all </s:Sequence> </s:Transition> <s:Transition fromState="addRecommend" toState="seeOther"> <s:Sequence> <s:Move yBy="50" target="{seeOthers}"/> </s:Sequence> </s:Transition> </s:transitions> <s:layout> <s:VerticalLayout paddingTop="15" paddingRight="10" paddingLeft="7"/> </s:layout> <button id="add" click=add_clickHandler(event)/> <button id="seeOthers"/>

    Read the article

  • Noob boost::bind member function callback question

    - by shaz
    #include <boost/bind.hpp> #include <iostream> using namespace std; using boost::bind; class A { public: void print(string &s) { cout << s.c_str() << endl; } }; typedef void (*callback)(); class B { public: void set_callback(callback cb) { m_cb = cb; } void do_callback() { m_cb(); } private: callback m_cb; }; void main() { A a; B b; string s("message"); b.set_callback(bind(A::print, &a, s)); b.do_callback(); } So what I'm trying to do is to have the print method of A stream "message" to cout when b's callback is activated. I'm getting an unexpected number of arguments error from msvc10. I'm sure this is super noob basic and I'm sorry in advance.

    Read the article

  • authentication question (security code generation logic)

    - by Stick it to THE MAN
    I have a security number generator device, small enough to go on a key-ring, which has a six digit LCD display and a button. After I have entered my account name and password on an online form, I press the button on the security device and enter the security code number which is displayed. I get a different number every time I press the button and the number generator has a serial number on the back which I had to input during the account set-up procedure. I would like to incorporate similar functionality in my website. As far as I understand, these are the main components: Generate a unique N digit aplha-numeric sequence during registration and assign to user (permanently) Allow user to generate an N (or M?) digit aplha-numeric sequence remotely For now, I dont care about the hardware side, I am only interested in knowing how I may choose a suitable algorithm that will allow the user to generate an N (or M?) long aplha-numeric sequence - presumably, using his unique ID as a seed Identify the user from the number generated in step 2 (which decryption method is the most robust to do this?) I have the following questions: Have I identified all the steps required in such an authentication system?, if not please point out what I have missed and why it is important What are the most robust encryption/decryption algorithms I can use for steps 1 through 3 (preferably using 64bits)?

    Read the article

  • @property, setter and getter question?

    - by fuzzygoat
    NSString *statusValue; NSString *currentValue; @property(retain, nonatomic) NSString *statusValue; @property(retain, nonatomic) NSString *currentValue; @synthesize statusValue; @sythnesize currentValue; Given the above, if I am setting one variable to another is it work doing ... [self setStatusValue: currentValue]; or should I use the property again and use [self setStatusValue: [self currentValue]]; I suppose the latter (although maybe overkill) does tell the reader that we are using one of the objects instance variables and not some local variable. just curious really ... gary

    Read the article

  • Best practise question

    - by sid_com
    Hello! With version would you prefer? #!/usr/bin/env perl use warnings; use strict; use 5.010; my $p = 7; # 33 my $prompt = ' : '; my $key = 'very important text'; my $value = 'Hello, World!'; my $length = length $key . $prompt; $p -= $length; Option 1: $key = $key . ' ' x $p . $prompt; Option 2: if ( $p > 0 ) { $key = $key . ' ' x $p . $prompt; } else { $key = $key . $prompt; } say "$key$value"

    Read the article

< Previous Page | 106 107 108 109 110 111 112 113 114 115 116 117  | Next Page >