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  • Using Event Driven Programming in games, when is it beneficial?

    - by Arthur Wulf White
    I am learning ActionScript 3 and I see the Event flow adheres to the W3C recommendations. From what I learned events can only be captured by the dispatcher unless, the listener capturing the event is a DisplayObject on stage and a parent of the object firing the event. You can capture the events in the capture(before) or bubbling(after) phase depending on Listner and Event setup you use. Does this system lend itself well for game programming? When is this system useful? Could you give an example of a case where using events is a lot better than going without them? Are they somehow better for performance in games? Please do not mention events you must use to get a game running, like Event.ENTER_FRAME Or events that are required to get input from the user like, KeyboardEvent.KEY_DOWN and MouseEvent.CLICK. I am asking if there is any use in firing events that have nothing to do with user input, frame rendering and the likes(that are necessary). I am referring to cases where objects are communicating. Is this used to avoid storing a collection of objects that are on the stage? Thanks Here is some code I wrote as an example of event behavior in ActionScript 3, enjoy. package regression { import flash.display.Shape; import flash.display.Sprite; import flash.events.Event; import flash.events.EventDispatcher; import flash.events.KeyboardEvent; import flash.events.MouseEvent; import flash.events.EventPhase; /** * ... * @author ... */ public class Check_event_listening_1 extends Sprite { public const EVENT_DANCE : String = "dance"; public const EVENT_PLAY : String = "play"; public const EVENT_YELL : String = "yell"; private var baby : Shape = new Shape(); private var mom : Sprite = new Sprite(); private var stranger : EventDispatcher = new EventDispatcher(); public function Check_event_listening_1() { if (stage) init(); else addEventListener(Event.ADDED_TO_STAGE, init); } private function init(e:Event = null):void { trace("test begun"); addChild(mom); mom.addChild(baby); stage.addEventListener(EVENT_YELL, onEvent); this.addEventListener(EVENT_YELL, onEvent); mom.addEventListener(EVENT_YELL, onEvent); baby.addEventListener(EVENT_YELL, onEvent); stranger.addEventListener(EVENT_YELL, onEvent); trace("\nTest1 - Stranger yells with no bubbling"); stranger.dispatchEvent(new Event(EVENT_YELL, false)); trace("\nTest2 - Stranger yells with bubbling"); stranger.dispatchEvent(new Event(EVENT_YELL, true)); stage.addEventListener(EVENT_PLAY, onEvent); this.addEventListener(EVENT_PLAY, onEvent); mom.addEventListener(EVENT_PLAY, onEvent); baby.addEventListener(EVENT_PLAY, onEvent); stranger.addEventListener(EVENT_PLAY, onEvent); trace("\nTest3 - baby plays with no bubbling"); baby.dispatchEvent(new Event(EVENT_PLAY, false)); trace("\nTest4 - baby plays with bubbling"); baby.dispatchEvent(new Event(EVENT_PLAY, true)); trace("\nTest5 - baby plays with bubbling but is not a child of mom"); mom.removeChild(baby); baby.dispatchEvent(new Event(EVENT_PLAY, true)); mom.addChild(baby); stage.addEventListener(EVENT_DANCE, onEvent, true); this.addEventListener(EVENT_DANCE, onEvent, true); mom.addEventListener(EVENT_DANCE, onEvent, true); baby.addEventListener(EVENT_DANCE, onEvent); trace("\nTest6 - Mom dances without bubbling - everyone is listening during capture phase(not target and bubble phase)"); mom.dispatchEvent(new Event(EVENT_DANCE, false)); trace("\nTest7 - Mom dances with bubbling - everyone is listening during capture phase(not target and bubble phase)"); mom.dispatchEvent(new Event(EVENT_DANCE, true)); } private function onEvent(e : Event):void { trace("Event was captured"); trace("\nTYPE : ", e.type, "\nTARGET : ", objToName(e.target), "\nCURRENT TARGET : ", objToName(e.currentTarget), "\nPHASE : ", phaseToString(e.eventPhase)); } private function phaseToString(phase : int):String { switch(phase) { case EventPhase.AT_TARGET : return "TARGET"; case EventPhase.BUBBLING_PHASE : return "BUBBLING"; case EventPhase.CAPTURING_PHASE : return "CAPTURE"; default: return "UNKNOWN"; } } private function objToName(obj : Object):String { if (obj == stage) return "STAGE"; else if (obj == this) return "MAIN"; else if (obj == mom) return "Mom"; else if (obj == baby) return "Baby"; else if (obj == stranger) return "Stranger"; else return "Unknown" } } } /*result : test begun Test1 - Stranger yells with no bubbling Event was captured TYPE : yell TARGET : Stranger CURRENT TARGET : Stranger PHASE : TARGET Test2 - Stranger yells with bubbling Event was captured TYPE : yell TARGET : Stranger CURRENT TARGET : Stranger PHASE : TARGET Test3 - baby plays with no bubbling Event was captured TYPE : play TARGET : Baby CURRENT TARGET : Baby PHASE : TARGET Test4 - baby plays with bubbling Event was captured TYPE : play TARGET : Baby CURRENT TARGET : Baby PHASE : TARGET Event was captured TYPE : play TARGET : Baby CURRENT TARGET : Mom PHASE : BUBBLING Event was captured TYPE : play TARGET : Baby CURRENT TARGET : MAIN PHASE : BUBBLING Event was captured TYPE : play TARGET : Baby CURRENT TARGET : STAGE PHASE : BUBBLING Test5 - baby plays with bubbling but is not a child of mom Event was captured TYPE : play TARGET : Baby CURRENT TARGET : Baby PHASE : TARGET Test6 - Mom dances without bubbling - everyone is listening during capture phase(not target and bubble phase) Event was captured TYPE : dance TARGET : Mom CURRENT TARGET : STAGE PHASE : CAPTURE Event was captured TYPE : dance TARGET : Mom CURRENT TARGET : MAIN PHASE : CAPTURE Test7 - Mom dances with bubbling - everyone is listening during capture phase(not target and bubble phase) Event was captured TYPE : dance TARGET : Mom CURRENT TARGET : STAGE PHASE : CAPTURE Event was captured TYPE : dance TARGET : Mom CURRENT TARGET : MAIN PHASE : CAPTURE */

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  • When to use identity comparison instead of equals?

    - by maaartinus
    I wonder why would anybody want to use identity comparison for fields in equals, like here (Java syntax): class C { private A a; public boolean equals(Object other) { // standard boring prelude if (other==this) return true; if (other==null) return false; if (other.getClass() != this.getClass()) return false; C c = (C) other; // the relevant part if (c.a != this.a) return false; // more tests... and then return true; } // getter, setters, hashCode, ... } Using == is a bit faster than equals and a bit shorter (due to no need for null tests), too, but in what cases (if any) you'd say it's really better to use == for fields inside equals?

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  • Functions returning pointers

    - by fg nu
    C++ noob here. I have a very basic question about a construct I found in the C++ book I am reading. // class declaration class CStr { char sData[256]; public: char* get(void); }; // implementation of the function char* CStr::get(void) { return sData; } So the Cstr::get function is obviously meant to return a character pointer, but the function is passing what looks like the value (return sData). Does C++ know to return the address of the returned object? My guess would have been that the function definition would be return &sData.

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  • most efficient AABB vs Ray collision algorithms

    - by Asher Einhorn
    Is there a known 'most efficient' algorithm for AABB vs Ray collision detection? I recently stumbled accross Arvo's AABB vs Sphere collision algorithm, and I am wondering if there is a similarly noteworthy algorithm for this. One must have condition for this algorithm is that I need to have the option of querying the result for the distance from the ray's origin to the point of collision. having said this, if there is another, faster algorithm which does not return distance, then in addition to posting one that does, also posting that algorithm would be very helpful indeed. Please also state what the function's return argument is, and how you use it to return distance or a 'no-collision' case. For example, does it have an out parameter for the distance as well as a bool return value? or does it simply return a float with the distance, vs a value of -1 for no collision? (For those that don't know: AABB = Axis Aligned Bounding Box)

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  • Triangle Picking Picking Back faces

    - by Tangeleno
    I'm having a bit of trouble with 3D picking, at first I thought my ray was inaccurate but it turns out that the picking is happening on faces facing the camera and faces facing away from the camera which I'm currently culling. Here's my ray creation code, I'm pretty sure the problem isn't here but I've been wrong before. private uint Pick() { Ray cursorRay = CalculateCursorRay(); Vector3? point = Control.Mesh.RayCast(cursorRay); if (point != null) { Tile hitTile = Control.TileMesh.GetTileAtPoint(point); return hitTile == null ? uint.MaxValue : (uint)(hitTile.X + hitTile.Y * Control.Generator.TilesWide); } return uint.MaxValue; } private Ray CalculateCursorRay() { Vector3 nearPoint = Control.Camera.Unproject(new Vector3(Cursor.Position.X, Control.ClientRectangle.Height - Cursor.Position.Y, 0f)); Vector3 farPoint = Control.Camera.Unproject(new Vector3(Cursor.Position.X, Control.ClientRectangle.Height - Cursor.Position.Y, 1f)); Vector3 direction = farPoint - nearPoint; direction.Normalize(); return new Ray(nearPoint, direction); } public Vector3 Camera.Unproject(Vector3 source) { Vector4 result; result.X = (source.X - _control.ClientRectangle.X) * 2 / _control.ClientRectangle.Width - 1; result.Y = (source.Y - _control.ClientRectangle.Y) * 2 / _control.ClientRectangle.Height - 1; result.Z = source.Z - 1; if (_farPlane - 1 == 0) result.Z = 0; else result.Z = result.Z / (_farPlane - 1); result.W = 1f; result = Vector4.Transform(result, Matrix4.Invert(ProjectionMatrix)); result = Vector4.Transform(result, Matrix4.Invert(ViewMatrix)); result = Vector4.Transform(result, Matrix4.Invert(_world)); result = Vector4.Divide(result, result.W); return new Vector3(result.X, result.Y, result.Z); } And my triangle intersection code. Ripped mainly from the XNA picking sample. public float? Intersects(Ray ray) { float? closestHit = Bounds.Intersects(ray); if (closestHit != null && Vertices.Length == 3) { Vector3 e1, e2; Vector3.Subtract(ref Vertices[1].Position, ref Vertices[0].Position, out e1); Vector3.Subtract(ref Vertices[2].Position, ref Vertices[0].Position, out e2); Vector3 directionCrossEdge2; Vector3.Cross(ref ray.Direction, ref e2, out directionCrossEdge2); float determinant; Vector3.Dot(ref e1, ref directionCrossEdge2, out determinant); if (determinant > -float.Epsilon && determinant < float.Epsilon) return null; float inverseDeterminant = 1.0f/determinant; Vector3 distanceVector; Vector3.Subtract(ref ray.Position, ref Vertices[0].Position, out distanceVector); float triangleU; Vector3.Dot(ref distanceVector, ref directionCrossEdge2, out triangleU); triangleU *= inverseDeterminant; if (triangleU < 0 || triangleU > 1) return null; Vector3 distanceCrossEdge1; Vector3.Cross(ref distanceVector, ref e1, out distanceCrossEdge1); float triangleV; Vector3.Dot(ref ray.Direction, ref distanceCrossEdge1, out triangleV); triangleV *= inverseDeterminant; if (triangleV < 0 || triangleU + triangleV > 1) return null; float rayDistance; Vector3.Dot(ref e2, ref distanceCrossEdge1, out rayDistance); rayDistance *= inverseDeterminant; if (rayDistance < 0) return null; return rayDistance; } return closestHit; } I'll admit I don't fully understand all of the math behind the intersection and that is something I'm working on, but my understanding was that if rayDistance was less than 0 the face was facing away from the camera, and shouldn't be counted as a hit. So my question is, is there an issue with my intersection or ray creation code, or is there another check I need to perform to tell if the face is facing away from the camera, and if so any hints on what that check might contain would be appreciated.

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  • k-d tree implementation [closed]

    - by user466441
    when i run my code and debugged,i got this error - this 0x00093584 {_Myproxy=0x00000000 _Mynextiter=0x00000000 } std::_Iterator_base12 * const - _Myproxy 0x00000000 {_Mycont=??? _Myfirstiter=??? } std::_Container_proxy * _Mycont CXX0017: Error: symbol "" not found _Myfirstiter CXX0030: Error: expression cannot be evaluated + _Mynextiter 0x00000000 {_Myproxy=??? _Mynextiter=??? } std::_Iterator_base12 * but i dont know what does it means,code is this #include<iostream> #include<vector> #include<algorithm> using namespace std; struct point { float x,y; }; vector<point>pointleft(4); vector<point>pointright(4); //we are going to implement two comparison function for x and y coordinates,we need it in calculation of median (we should sort vector //by x or y according to depth informaton,is depth even or odd. bool sortby_X(point &a,point &b) { return a.x<b.x; } bool sortby_Y(point &a,point &b) { return a.y<b.y; } //so i am going to implement to median finding algorithm,one for finding median by x and another find median by y point medianx(vector<point>points) { point temp; sort(points.begin(),points.end(),sortby_X); temp=points[(points.size()/2)]; return temp; } point mediany(vector<point>points) { point temp; sort(points.begin(),points.end(),sortby_Y); temp=points[(points.size()/2)]; return temp; } //now construct basic tree structure struct Tree { float x,y; Tree(point a) { x=a.x; y=a.y; } Tree *left; Tree *right; }; Tree * build_kd( Tree *root,vector<point>points,int depth) { point temp; if(points.size()==1)// that point is as a leaf { if(root==NULL) root=new Tree(points[0]); return root; } if(depth%2==0) { temp=medianx(points); root=new Tree(temp); for(int i=0;i<points.size();i++) { if (points[i].x<temp.x) pointleft[i]=points[i]; else pointright[i]=points[i]; } } else { temp=mediany(points); root=new Tree(temp); for(int i=0;i<points.size();i++) { if(points[i].y<temp.y) pointleft[i]=points[i]; else pointright[i]=points[i]; } } return build_kd(root->left,pointleft,depth+1); return build_kd(root->right,pointright,depth+1); } void print(Tree *root) { while(root!=NULL) { cout<<root->x<<" " <<root->y; print(root->left); print(root->right); } } int main() { int depth=0; Tree *root=NULL; vector<point>points(4); float x,y; int n=4; for(int i=0;i<n;i++) { cin>>x>>y; points[i].x=x; points[i].y=y; } root=build_kd(root,points,depth); print(root); return 0; } i am trying ti implement in c++ this pseudo code tuple function build_kd_tree(int depth, set points): if points contains only one point: return that point as a leaf. if depth is even: Calculate the median x-value. Create a set of points (pointsLeft) that have x-values less than the median. Create a set of points (pointsRight) that have x-values greater than or equal to the median. else: Calculate the median y-value. Create a set of points (pointsLeft) that have y-values less than the median. Create a set of points (pointsRight) that have y-values greater than or equal to the median. treeLeft = build_kd_tree(depth + 1, pointsLeft) treeRight = build_kd_tree(depth + 1, pointsRight) return(median, treeLeft, treeRight) please help me what this error means?

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  • Whats steps can I suggest to achieve the best Geolocation Result [migrated]

    - by Matt
    We are using Geolocation (getCurrentPosition()) in a website to determine a users position when using our site from a mobile device. I want to write an article explaining how the user can obtain the best results. Am I correct in assuming: Enabling GPS will yield the best result when in rural areas (less buildings to obscure line of sight to the satelites) Enabling Wi-Fi will yield the best results when in urban areas (generally more Wi-Fi hotspots available) Is it true that Android phones have better results from silently harvesting Wi-Fi hotspot details? Any links to reference material on this are appreciated

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  • Passing class names or objects?

    - by nischayn22
    I have a switch statement switch ( $id ) { case 'abc': return 'Animal'; case 'xyz': return 'Human'; //many more } I am returning class names,and use them to call some of their static functions using call_user_func(). Instead I can also create a object of that class, return that and then call the static function from that object as $object::method($param) switch ( $id ) { case 'abc': return new Animal; case 'xyz': return new Human; //many more } Which way is efficient? To make this question broader : I have classes that have mostly all static methods right now, putting them into classes is kind of a grouping idea here (for example the DB table structure of Animal is given by class Animal and so for Human class). I need to access many functions from these classes so the switch needs to give me access to the class

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  • Friend wants to return an iMac with Lion in it. How does he remove his personal info / do clean install?

    - by fakaff
    I have a Mac, but not Lion, and it seems like a lot has changed with Lion. He wants to return the computer. I told him doing a clean install will make it like new, but he says you can't download a bootable disk image from the appstore to do this. He doesn't want to torrent it because he thinks the store will know it's a ripped version. Is there a way for him to remove his Admin account so that none of his personal info remians on the machine?

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  • C# serial port driver wrapper class code and concept quality

    - by Ruben Trancoso
    Hi folks, Would like to know from all you guys what you think about my Serial Wrapper class. Had be a while I've beem working with serial port but never shared the code what somekind make closed to my very own vision. Would like to know if it's a good/bad approach, if the interface is enough and what more you see on it. I know that Stackoverflow is for question but at the same time there's a lot of very good skilled people here and share code and opinion can also bennefit everybody, it's why I decided to post it anyway. thanks! using System.Text; using System.IO; using System.IO.Ports; using System; namespace Driver { class SerialSingleton { // The singleton instance reference private static SerialSingleton instance = null; // System's serial port interface private SerialPort serial; // Current com port identifier private string comPort = null; // Configuration parameters private int confBaudRate; private int confDataBits; private StopBits confStopBits; private Parity confParityControl; ASCIIEncoding encoding = new ASCIIEncoding(); // ================================================================================== // Constructors public static SerialSingleton getInstance() { if (instance == null) { instance = new SerialSingleton(); } return instance; } private SerialSingleton() { serial = new SerialPort(); } // =================================================================================== // Setup Methods public string ComPort { get { return comPort; } set { if (value == null) { throw new SerialException("Serial port name canot be null."); } if (nameIsComm(value)) { close(); comPort = value; } else { throw new SerialException("Serial Port '" + value + "' is not a valid com port."); } } } public void setSerial(string baudRate, int dataBits, StopBits stopBits, Parity parityControl) { if (baudRate == null) { throw new SerialException("Baud rate cannot be null"); } string[] baudRateRef = { "300", "600", "1200", "1800", "2400", "3600", "4800", "7200", "9600", "14400", "19200", "28800", "38400", "57600", "115200" }; int confBaudRate; if (findString(baudRateRef, baudRate) != -1) { confBaudRate = System.Convert.ToInt32(baudRate); } else { throw new SerialException("Baurate parameter invalid."); } int confDataBits; switch (dataBits) { case 5: confDataBits = 5; break; case 6: confDataBits = 6; break; case 7: confDataBits = 7; break; case 8: confDataBits = 8; break; default: throw new SerialException("Databits parameter invalid"); } if (stopBits == StopBits.None) { throw new SerialException("StopBits parameter cannot be NONE"); } this.confBaudRate = confBaudRate; this.confDataBits = confDataBits; this.confStopBits = stopBits; this.confParityControl = parityControl; } // ================================================================================== public string[] PortList { get { return SerialPort.GetPortNames(); } } public int PortCount { get { return SerialPort.GetPortNames().Length; } } // ================================================================================== // Open/Close Methods public void open() { open(comPort); } private void open(string comPort) { if (isOpen()) { throw new SerialException("Serial Port is Already open"); } else { if (comPort == null) { throw new SerialException("Serial Port not defined. Cannot open"); } bool found = false; if (nameIsComm(comPort)) { string portId; string[] portList = SerialPort.GetPortNames(); for (int i = 0; i < portList.Length; i++) { portId = (portList[i]); if (portId.Equals(comPort)) { found = true; break; } } } else { throw new SerialException("The com port identifier '" + comPort + "' is not a valid serial port identifier"); } if (!found) { throw new SerialException("Serial port '" + comPort + "' not found"); } serial.PortName = comPort; try { serial.Open(); } catch (UnauthorizedAccessException uaex) { throw new SerialException("Cannot open a serial port in use by another application", uaex); } try { serial.BaudRate = confBaudRate; serial.DataBits = confDataBits; serial.Parity = confParityControl; serial.StopBits = confStopBits; } catch (Exception e) { throw new SerialException("Serial port parameter invalid for '" + comPort + "'.\n" + e.Message, e); } } } public void close() { if (serial.IsOpen) { serial.Close(); } } // =================================================================================== // Auxiliary private Methods private int findString(string[] set, string search) { if (set != null) { for (int i = 0; i < set.Length; i++) { if (set[i].Equals(search)) { return i; } } } return -1; } private bool nameIsComm(string name) { int comNumber; int.TryParse(name.Substring(3), out comNumber); if (name.Substring(0, 3).Equals("COM")) { if (comNumber > -1 && comNumber < 256) { return true; } } return false; } // ================================================================================= // Device state Methods public bool isOpen() { return serial.IsOpen; } public bool hasData() { int amount = serial.BytesToRead; if (amount > 0) { return true; } else { return false; } } // ================================================================================== // Input Methods public char getChar() { int data = serial.ReadByte(); return (char)data; } public int getBytes(ref byte[] b) { int size = b.Length; char c; int counter = 0; for (counter = 0; counter < size; counter++) { if (tryGetChar(out c)) { b[counter] = (byte)c; } else { break; } } return counter; } public string getStringUntil(char x) { char c; string response = ""; while (tryGetChar(out c)) { response = response + c; if (c == x) { break; } } return response; } public bool tryGetChar(out char c) { c = (char)0x00; byte[] b = new byte[1]; long to = 10; long ft = System.Environment.TickCount + to; while (System.Environment.TickCount < ft) { if (hasData()) { int data = serial.ReadByte(); c = (char)data; return true; } } return false; } // ================================================================================ // Output Methods public void sendString(string data) { byte[] bytes = encoding.GetBytes(data); serial.Write(bytes, 0, bytes.Length); } public void sendChar(char c) { char[] data = new char[1]; data[0] = c; serial.Write(data, 0, 1); } public void sendBytes(byte[] data) { serial.Write(data, 0, data.Length); } public void clearBuffer() { if (serial.IsOpen) { serial.DiscardInBuffer(); serial.DiscardOutBuffer(); } } } }

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  • Optimizing a lot of Scanner.findWithinHorizon(pattern, 0) calls

    - by darvids0n
    I'm building a process which extracts data from 6 csv-style files and two poorly laid out .txt reports and builds output CSVs, and I'm fully aware that there's going to be some overhead searching through all that whitespace thousands of times, but I never anticipated converting about about 50,000 records would take 12 hours. Excerpt of my manual matching code (I know it's horrible that I use lists of tokens like that, but it was the best thing I could think of): public static String lookup(List<String> tokensBefore, List<String> tokensAfter) { String result = null; while(_match(tokensBefore)) { // block until all input is read if(id.hasNext()) { result = id.next(); // capture the next token that matches if(_matchImmediate(tokensAfter)) // try to match tokensAfter to this result return result; } else return null; // end of file; no match } return null; // no matches } private static boolean _match(List<String> tokens) { return _match(tokens, true); } private static boolean _match(List<String> tokens, boolean block) { if(tokens != null && !tokens.isEmpty()) { if(id.findWithinHorizon(tokens.get(0), 0) == null) return false; for(int i = 1; i <= tokens.size(); i++) { if (i == tokens.size()) { // matches all tokens return true; } else if(id.hasNext() && !id.next().matches(tokens.get(i))) { break; // break to blocking behaviour } } } else { return true; // empty list always matches } if(block) return _match(tokens); // loop until we find something or nothing else return false; // return after just one attempted match } private static boolean _matchImmediate(List<String> tokens) { if(tokens != null) { for(int i = 0; i <= tokens.size(); i++) { if (i == tokens.size()) { // matches all tokens return true; } else if(!id.hasNext() || !id.next().matches(tokens.get(i))) { return false; // doesn't match, or end of file } } return false; // we have some serious problems if this ever gets called } else { return true; // empty list always matches } } Basically wondering how I would work in an efficient string search (Boyer-Moore or similar). My Scanner id is scanning a java.util.String, figured buffering it to memory would reduce I/O since the search here is being performed thousands of times on a relatively small file. The performance increase compared to scanning a BufferedReader(FileReader(File)) was probably less than 1%, the process still looks to be taking a LONG time. I've also traced execution and the slowness of my overall conversion process is definitely between the first and last like of the lookup method. In fact, so much so that I ran a shortcut process to count the number of occurrences of various identifiers in the .csv-style files (I use 2 lookup methods, this is just one of them) and the process completed indexing approx 4 different identifiers for 50,000 records in less than a minute. Compared to 12 hours, that's instant. Some notes (updated): I don't necessarily need the pattern-matching behaviour, I only get the first field of a line of text so I need to match line breaks or use Scanner.nextLine(). All ID numbers I need start at position 0 of a line and run through til the first block of whitespace, after which is the name of the corresponding object. I would ideally want to return a String, not an int locating the line number or start position of the result, but if it's faster then it will still work just fine. If an int is being returned, however, then I would now have to seek to that line again just to get the ID; storing the ID of every line that is searched sounds like a way around that. Anything to help me out, even if it saves 1ms per search, will help, so all input is appreciated. Thankyou! Usage scenario 1: I have a list of objects in file A, who in the old-style system have an id number which is not in file A. It is, however, POSSIBLY in another csv-style file (file B) or possibly still in a .txt report (file C) which each also contain a bunch of other information which is not useful here, and so file B needs to be searched through for the object's full name (1 token since it would reside within the second column of any given line), and then the first column should be the ID number. If that doesn't work, we then have to split the search token by whitespace into separate tokens before doing a search of file C for those tokens as well. Generalised code: String field; for (/* each record in file A */) { /* construct the rest of this object from file A info */ // now to find the ID, if we can List<String> objectName = new ArrayList<String>(1); objectName.add(Pattern.quote(thisObject.fullName)); field = lookup(objectSearchToken, objectName); // search file B if(field == null) // not found in file B { lookupReset(false); // initialise scanner to check file C objectName.clear(); // not using the full name String[] tokens = thisObject.fullName.split(id.delimiter().pattern()); for(String s : tokens) objectName.add(Pattern.quote(s)); field = lookup(objectSearchToken, objectName); // search file C lookupReset(true); // back to file B } else { /* found it, file B specific processing here */ } if(field != null) // found it in B or C thisObject.ID = field; } The objectName tokens are all uppercase words with possible hyphens or apostrophes in them, separated by spaces. Much like a person's name. As per a comment, I will pre-compile the regex for my objectSearchToken, which is just [\r\n]+. What's ending up happening in file C is, every single line is being checked, even the 95% of lines which don't contain an ID number and object name at the start. Would it be quicker to use ^[\r\n]+.*(objectname) instead of two separate regexes? It may reduce the number of _match executions. The more general case of that would be, concatenate all tokensBefore with all tokensAfter, and put a .* in the middle. It would need to be matching backwards through the file though, otherwise it would match the correct line but with a huge .* block in the middle with lots of lines. The above situation could be resolved if I could get java.util.Scanner to return the token previous to the current one after a call to findWithinHorizon. I have another usage scenario. Will put it up asap.

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  • How can I get the following compiled on UVA?

    - by Michael Tsang
    Note the comment below. It cannot compiled on UVA because of a bug in GCC. #include <cstdio> #include <cstring> #include <cctype> #include <map> #include <stdexcept> class Board { public: bool read(FILE *); enum Colour {none, white, black}; Colour check() const; private: struct Index { size_t x; size_t y; Index &operator+=(const Index &) throw(std::range_error); Index operator+(const Index &) const throw(std::range_error); }; const static std::size_t size = 8; char data[size][size]; // Cannot be compiled on GCC 4.1.2 due to GCC bug 29993 // http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29993 typedef bool CheckFunction(Colour, const Index &) const; CheckFunction pawn, knight, bishop, king, rook; bool queen(const Colour c, const Index &location) const { return rook(c, location) || bishop(c, location); } static char get_king(Colour c) { return c == white ? 'k' : 'K'; } template<std::size_t n> bool check_consecutive(Colour c, const Index &location, const Index (&offsets)[n]) const { for(const Index *p = offsets; p != (&offsets)[1]; ++p) { try { Index target = location + *p; for(; data[target.x][target.y] == '.'; target += *p) { } if(data[target.x][target.y] == get_king(c)) return true; } catch(std::range_error &) { } } return false; } template<std::size_t n> bool check_distinct(Colour c, const Index &location, const Index (&offsets)[n]) const { for(const Index *p = offsets; p != (&offsets)[1]; ++p) { try { Index target = location + *p; if(data[target.x][target.y] == get_king(c)) return true; } catch(std::range_error &) { } } return false; } }; int main() { Board board; for(int d = 1; board.read(stdin); ++d) { Board::Colour c = board.check(); const char *sp; switch(c) { case Board::black: sp = "white"; break; case Board::white: sp = "black"; break; case Board::none: sp = "no"; break; } std::printf("Game #%d: %s king is in check.\n", d, sp); std::getchar(); // discard empty line } } bool Board::read(FILE *f) { static const char empty[] = "........" "........" "........" "........" "........" "........" "........" "........"; // 64 dots for(char (*p)[size] = data; p != (&data)[1]; ++p) { std::fread(*p, size, 1, f); std::fgetc(f); // discard new-line } return std::memcmp(empty, data, sizeof data); } Board::Colour Board::check() const { std::map<char, CheckFunction Board::*> fp; fp['P'] = &Board::pawn; fp['N'] = &Board::knight; fp['B'] = &Board::bishop; fp['Q'] = &Board::queen; fp['K'] = &Board::king; fp['R'] = &Board::rook; for(std::size_t i = 0; i != size; ++i) { for(std::size_t j = 0; j != size; ++j) { CheckFunction Board::* p = fp[std::toupper(data[i][j])]; if(p) { Colour ret; if(std::isupper(data[i][j])) ret = white; else ret = black; if((this->*p)(ret, (Index){i, j}/* C99 extension */)) return ret; } } } return none; } bool Board::pawn(const Colour c, const Index &location) const { const std::ptrdiff_t sh = c == white ? -1 : 1; const Index offsets[] = { {sh, 1}, {sh, -1} }; return check_distinct(c, location, offsets); } bool Board::knight(const Colour c, const Index &location) const { static const Index offsets[] = { {1, 2}, {2, 1}, {2, -1}, {1, -2}, {-1, -2}, {-2, -1}, {-2, 1}, {-1, 2} }; return check_distinct(c, location, offsets); } bool Board::bishop(const Colour c, const Index &location) const { static const Index offsets[] = { {1, 1}, {1, -1}, {-1, -1}, {-1, 1} }; return check_consecutive(c, location, offsets); } bool Board::rook(const Colour c, const Index &location) const { static const Index offsets[] = { {1, 0}, {0, -1}, {0, 1}, {-1, 0} }; return check_consecutive(c, location, offsets); } bool Board::king(const Colour c, const Index &location) const { static const Index offsets[] = { {-1, -1}, {-1, 0}, {-1, 1}, {0, 1}, {1, 1}, {1, 0}, {1, -1}, {0, -1} }; return check_distinct(c, location, offsets); } Board::Index &Board::Index::operator+=(const Index &rhs) throw(std::range_error) { if(x + rhs.x >= size || y + rhs.y >= size) throw std::range_error("result is larger than size"); x += rhs.x; y += rhs.y; return *this; } Board::Index Board::Index::operator+(const Index &rhs) const throw(std::range_error) { Index ret = *this; return ret += rhs; }

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  • Implementing union of Set using basic java array

    - by lupindeterd
    Note: This is an assignment. Hi, Continuing with my Set implementation using Java basic array, I'm now struggling with the 3 to last function namely the union. import java.io.*; class Set { private int numberOfElements = 0; private String[] setElements = new String[5]; private int maxNumberOfElements = 5; // constructor for our Set class public Set(int numberOfE, int setE, int maxNumberOfE) { int numberOfElements = numberOfE; String[] setElements = new String[setE]; int maxNumberOfElements = maxNumberOfE; } // Helper method to shorten/remove element of array since we're using basic array instead of ArrayList or HashSet from collection interface :( static String[] removeAt(int k, String[] arr) { final int L = arr.length; String[] ret = new String[L - 1]; System.arraycopy(arr, 0, ret, 0, k); System.arraycopy(arr, k + 1, ret, k, L - k - 1); return ret; } int findElement(String element) { int retval = 0; for ( int i = 0; i < setElements.length; i++) { if ( setElements[i] != null && setElements[i].equals(element) ) { return retval = i; } retval = -1; } return retval; } void add(String newValue) { int elem = findElement(newValue); if( numberOfElements < maxNumberOfElements && elem == -1 ) { setElements[numberOfElements] = newValue; numberOfElements++; } } int getLength() { if ( setElements != null ) { return setElements.length; } else { return 0; } } String[] emptySet() { setElements = new String[0]; return setElements; } Boolean isFull() { Boolean True = new Boolean(true); Boolean False = new Boolean(false); if ( setElements.length == maxNumberOfElements ){ return True; } else { return False; } } Boolean isEmpty() { Boolean True = new Boolean(true); Boolean False = new Boolean(false); if ( setElements.length == 0 ) { return True; } else { return False; } } void remove(String newValue) { for ( int i = 0; i < setElements.length; i++) { if ( setElements[i].equals(newValue) ) { setElements = removeAt(i,setElements); } } } int isAMember(String element) { int retval = -1; for ( int i = 0; i < setElements.length; i++ ) { if (setElements[i] != null && setElements[i].equals(element)) { return retval = i; } } return retval; } void printSet() { for ( int i = 0; i < setElements.length; i++) { System.out.println("Member elements on index: "+ i +" " + setElements[i]); } } String[] getMember() { String[] tempArray = new String[setElements.length]; for ( int i = 0; i < setElements.length; i++) { if(setElements[i] != null) { tempArray[i] = setElements[i]; } } return tempArray; } Set union(Set x, Set y) { String[] newtemparray = new String[x.getLength]; newtemparray = x.getMember; return x; } } // This is the SetDemo class that will make use of our Set class class SetDemo { public static void main(String[] args) { //get input from keyboard BufferedReader keyboard; InputStreamReader reader; String temp = ""; reader = new InputStreamReader(System.in); keyboard = new BufferedReader(reader); try { System.out.println("Enter string element to be added" ); temp = keyboard.readLine( ); System.out.println("You entered " + temp ); } catch (IOException IOerr) { System.out.println("There was an error during input"); } /* ************************************************************************** * Test cases for our new created Set class. * ************************************************************************** */ Set setA = new Set(1,10,10); setA.add(temp); setA.add("b"); setA.add("b"); setA.add("hello"); setA.add("world"); setA.add("six"); setA.add("seven"); setA.add("b"); int size = setA.getLength(); System.out.println("Set size is: " + size ); Boolean isempty = setA.isEmpty(); System.out.println("Set is empty? " + isempty ); int ismember = setA.isAMember("sixb"); System.out.println("Element six is member of setA? " + ismember ); Boolean output = setA.isFull(); System.out.println("Set is full? " + output ); setA.printSet(); int index = setA.findElement("world"); System.out.println("Element b located on index: " + index ); setA.remove("b"); setA.emptySet(); int resize = setA.getLength(); System.out.println("Set size is: " + resize ); setA.printSet(); Set setB = new Set(0,10,10); Set SetA = setA.union(setB,setA); } } Ok the method in question will be the implementation of union. As such this: Set union(Set x, Set y) { String[] newtemparray = new String[x.getLength]; newtemparray = x.getMember; return x; } I got this error: symbol : variable getLength location: class Set String[] newtemparray = new String[x.getLength]; ^ d:\javaprojects\Set.java:122: cannot find symbol symbol : variable getMember location: class Set newtemparray = x.getMember; ^ 2 errors My approach for union would be: *) create temporary array of string with size of the object x length. *) store object x members to temporary array by looping the object and calling the getMember *) loop object y members and check if element exist against temporary array. *) discard if it exist/add if it is not there *) return obj x with the union array. thanks, lupin

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  • Returning new object, overwrite the existing one in Java

    - by lupin
    Note: This is an assignment. Hi, Ok I have this method that will create a supposedly union of 2 sets. i mport java.io.*; class Set { public int numberOfElements; public String[] setElements; public int maxNumberOfElements; // constructor for our Set class public Set(int numberOfE, int setE, int maxNumberOfE) { this.numberOfElements = numberOfE; this.setElements = new String[setE]; this.maxNumberOfElements = maxNumberOfE; } // Helper method to shorten/remove element of array since we're using basic array instead of ArrayList or HashSet from collection interface :( static String[] removeAt(int k, String[] arr) { final int L = arr.length; String[] ret = new String[L - 1]; System.arraycopy(arr, 0, ret, 0, k); System.arraycopy(arr, k + 1, ret, k, L - k - 1); return ret; } int findElement(String element) { int retval = 0; for ( int i = 0; i < setElements.length; i++) { if ( setElements[i] != null && setElements[i].equals(element) ) { return retval = i; } retval = -1; } return retval; } void add(String newValue) { int elem = findElement(newValue); if( numberOfElements < maxNumberOfElements && elem == -1 ) { setElements[numberOfElements] = newValue; numberOfElements++; } } int getLength() { if ( setElements != null ) { return setElements.length; } else { return 0; } } String[] emptySet() { setElements = new String[0]; return setElements; } Boolean isFull() { Boolean True = new Boolean(true); Boolean False = new Boolean(false); if ( setElements.length == maxNumberOfElements ){ return True; } else { return False; } } Boolean isEmpty() { Boolean True = new Boolean(true); Boolean False = new Boolean(false); if ( setElements.length == 0 ) { return True; } else { return False; } } void remove(String newValue) { for ( int i = 0; i < setElements.length; i++) { if ( setElements[i] != null && setElements[i].equals(newValue) ) { setElements = removeAt(i,setElements); } } } int isAMember(String element) { int retval = -1; for ( int i = 0; i < setElements.length; i++ ) { if (setElements[i] != null && setElements[i].equals(element)) { return retval = i; } } return retval; } void printSet() { for ( int i = 0; i < setElements.length; i++) { if (setElements[i] != null) { System.out.println("Member elements on index: "+ i +" " + setElements[i]); } } } String[] getMember() { String[] tempArray = new String[setElements.length]; for ( int i = 0; i < setElements.length; i++) { if(setElements[i] != null) { tempArray[i] = setElements[i]; } } return tempArray; } Set union(Set x, Set y) { String[] newXtemparray = new String[x.getLength()]; String[] newYtemparray = new String[y.getLength()]; int len = newYtemparray.length + newXtemparray.length; Set temp = new Set(0,len,len); newXtemparray = x.getMember(); newYtemparray = x.getMember(); for(int i = 0; i < newYtemparray.length; i++) { temp.add(newYtemparray[i]); } for(int j = 0; j < newXtemparray.length; j++) { temp.add(newXtemparray[j]); } return temp; } Set difference(Set x, Set y) { String[] newXtemparray = new String[x.getLength()]; String[] newYtemparray = new String[y.getLength()]; int len = newYtemparray.length + newXtemparray.length; Set temp = new Set(0,len,len); newXtemparray = x.getMember(); newYtemparray = x.getMember(); for(int i = 0; i < newXtemparray.length; i++) { temp.add(newYtemparray[i]); } for(int j = 0; j < newYtemparray.length; j++) { int retval = temp.findElement(newYtemparray[j]); if( retval != -1 ) { temp.remove(newYtemparray[j]); } } return temp; } } // This is the SetDemo class that will make use of our Set class class SetDemo { public static void main(String[] args) { //get input from keyboard BufferedReader keyboard; InputStreamReader reader; String temp = ""; reader = new InputStreamReader(System.in); keyboard = new BufferedReader(reader); try { System.out.println("Enter string element to be added" ); temp = keyboard.readLine( ); System.out.println("You entered " + temp ); } catch (IOException IOerr) { System.out.println("There was an error during input"); } /* ************************************************************************** * Test cases for our new created Set class. * ************************************************************************** */ Set setA = new Set(0,10,10); setA.add(temp); setA.add("b"); setA.add("b"); setA.add("hello"); setA.add("world"); setA.add("six"); setA.add("seven"); setA.add("b"); int size = setA.getLength(); System.out.println("Set size is: " + size ); Boolean isempty = setA.isEmpty(); System.out.println("Set is empty? " + isempty ); int ismember = setA.isAMember("sixb"); System.out.println("Element sixb is member of setA? " + ismember ); Boolean output = setA.isFull(); System.out.println("Set is full? " + output ); //setA.printSet(); int index = setA.findElement("world"); System.out.println("Element b located on index: " + index ); setA.remove("b"); //setA.emptySet(); int resize = setA.getLength(); System.out.println("Set size is: " + resize ); //setA.printSet(); Set setB = new Set(0,10,10); setB.add("b"); setB.add("z"); setB.add("x"); setB.add("y"); Set setC = setA.union(setB,setA); System.out.println("Elements of setA"); setA.printSet(); System.out.println("Union of setA and setB"); setC.printSet(); } } The union method works a sense that somehow I can call another method on it but it doesn't do the job, i supposedly would create and union of all elements of setA and setB but it only return element of setB. Sample output follows: java SetDemo Enter string element to be added hello You entered hello Set size is: 10 Set is empty? false Element sixb is member of setA? -1 Set is full? true Element b located on index: 2 Set size is: 9 Elements of setA Member elements on index: 0 hello Member elements on index: 1 world Member elements on index: 2 six Member elements on index: 3 seven Union of setA and setB Member elements on index: 0 b Member elements on index: 1 z Member elements on index: 2 x Member elements on index: 3 y thanks, lupin

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  • User controls Stopped working after Migration from 3.7 to 5.2

    - by user1400290
    I recently Migrated my 3.7 sp4 project to 5.2, but I had issues while doing so. Currently, my user controls are not working after migration in 5.2 project. Below is the code: User Control Code: <%@ Control Language="C#" AutoEventWireup="true" CodeFile="SiteMenu.ascx.cs" Inherits="UserControls_Nav_SiteMenu" %> <%@ Register TagPrefix="telerik" Assembly="Telerik.Web.UI" Namespace="Telerik.Web.UI" %> <asp:SiteMapDataSource ID="SiteMapDataSource1" runat="server" ShowStartingNode="false" /> <telerik:RadMenu ID="RadMenu1" runat="server" DataSourceID="SitemapDataSource1" OnItemDataBound="RadMenu1_ItemDataBound"> </telerik:RadMenu> User Control's Class code: using System; using System.Data; using System.Configuration; using System.Collections; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Web.UI.HtmlControls; using System.ComponentModel; using System.Drawing; using Telerik; using Telerik.Cms; using Telerik.Cms.Web; using Telerik.Web.UI; using Telerik.Caching; using Telerik.Cms.Web.UI; [DefaultProperty("StartingNodeOffset")] public partial class UserControls_Nav_SiteMenu : System.Web.UI.UserControl, ICacheableObject { protected void Page_Load(object sender, EventArgs e) { } protected override void Render(HtmlTextWriter writer) { // Checks if this is called by the Search Indexer and does not render anything if so. // Navigation controls are present in every page and should NOT be indexed multiple times. if (!CmsContext.IsRequestCrawler(this.Context)) base.Render(writer); } #region Data Fields private bool hideUrlForGroupPages = false; private string selectedItemCssClass = "selectedItem"; #endregion #region Properties [Browsable(true)] [Category("Behavior")] public int LastExpandLevel { get { if (this.RadMenu1.MaxDataBindDepth < 0) return 0; return this.RadMenu1.MaxDataBindDepth; } set { if (value == 0) this.RadMenu1.MaxDataBindDepth = -1; else this.RadMenu1.MaxDataBindDepth = value; } } [Browsable(true)] [Category("Behavior")] public int ExpandDelay { get { return this.RadMenu1.ExpandDelay; } set { this.RadMenu1.ExpandDelay = value; } } [Browsable(true)] [Category("Behavior")] public bool ClickToOpen { get { return this.RadMenu1.ClickToOpen; } set { this.RadMenu1.ClickToOpen = value; } } [Browsable(true)] [Category("Behavior")] [DefaultValue(false)] public bool HideUrlForGroupPages { get { return this.hideUrlForGroupPages; } set { this.hideUrlForGroupPages = value; } } [Browsable(true)] [Category("Appearance")] public string SelectedItemCssClass { get { return this.selectedItemCssClass; } set { this.selectedItemCssClass = value; } } [Browsable(true)] [Category("Appearance")] public string CssClass { get { return this.RadMenu1.CssClass; } set { this.RadMenu1.CssClass = value; } } [Browsable(true)] public RadMenu Menu { get { return this.RadMenu1; } set { this.RadMenu1 = value; } } [Browsable(true)] [Category("Navigation")] public int StartingNodeOffset { get { return this.SiteMapDataSource1.StartingNodeOffset; } set { this.SiteMapDataSource1.StartingNodeOffset = value; } } [WebEditor("Telerik.Cms.Web.UI.UrlEditorWrapper, Telerik.Cms")] [Browsable(true)] [Category("Navigation")] public string StartingNodeUrl { get { return this.SiteMapDataSource1.StartingNodeUrl; } set { this.SiteMapDataSource1.StartingNodeUrl = value; } } [Browsable(true)] [Category("Navigation")] public bool StartFromCurrentNode { get { return this.SiteMapDataSource1.StartFromCurrentNode; } set { this.SiteMapDataSource1.StartFromCurrentNode = value; } } [Browsable(true)] [Category("Navigation")] public bool ShowStartingNode { get { return this.SiteMapDataSource1.ShowStartingNode; } set { this.SiteMapDataSource1.ShowStartingNode = value; } } /// <summary>(Exposed from contained RadMenu.)</summary> [Browsable(true)] [Category("Appearance")] public string SkinID { get { return this.RadMenu1.SkinID; } set { this.RadMenu1.SkinID = value; } } [Browsable(true)] [Category("Appearance")] public string Skin { get { return this.RadMenu1.Skin; } set { this.RadMenu1.Skin = value; } } #endregion #region Methods public void RadMenu1_ItemDataBound(object sender, RadMenuEventArgs e) { CmsSiteMapNode node = e.Item.DataItem as CmsSiteMapNode; if (this.hideUrlForGroupPages) { if (node != null) { // save the PageID in the attributes of the menu item e.Item.Attributes.Add("PageID", node.Key); if (node.PageType == CmsPageType.Group) { e.Item.NavigateUrl = ""; } } } if (node.CmsPage != null) { if (node.CmsPage.PageType == CmsPageType.External) { e.Item.Target = "_blank"; } } } #endregion #region ICacheableObject Members public System.Web.Caching.CacheDependency[] GetDependencies() { CmsSiteMapProvider provider = null; if (!String.IsNullOrEmpty(this.SiteMapDataSource1.SiteMapProvider)) provider = SiteMap.Providers[this.SiteMapDataSource1.SiteMapProvider] as CmsSiteMapProvider; else provider = SiteMap.Provider as CmsSiteMapProvider; if (provider != null) { return new System.Web.Caching.CacheDependency[]{ provider.CloneCacheDependency()}; } return null; } #endregion } When I edit the Template(in Admin mode), the following error is displayed in control location: Both DataSource and DataSourceID are defined on 'RadMenu1'. Remove one definition. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.InvalidOperationException: Both DataSource and DataSourceID are defined on 'RadMenu1'. Remove one definition. Source Error: An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. Stack Trace: [InvalidOperationException: Both DataSource and DataSourceID are defined on 'RadMenu1'. Remove one definition.] System.Web.UI.WebControls.DataBoundControl.ConnectToDataSourceView() +3234866 System.Web.UI.WebControls.DataBoundControl.OnLoad(EventArgs e) +28 System.Web.UI.Control.LoadRecursive() +71 System.Web.UI.Control.LoadRecursive() +190 System.Web.UI.Control.LoadRecursive() +190 System.Web.UI.Control.AddedControl(Control control, Int32 index) +11422584 System.Web.UI.Control.EnsureChildControls() +182 System.Web.UI.Control.PreRenderRecursiveInternal() +60 System.Web.UI.Control.PreRenderRecursiveInternal() +222 System.Web.UI.Control.PreRenderRecursiveInternal() +222 System.Web.UI.Control.PreRenderRecursiveInternal() +222 System.Web.UI.Control.PreRenderRecursiveInternal() +222 System.Web.UI.Control.PreRenderRecursiveInternal() +222 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +4201 Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.272 but I searched in my code as you can see above there's only DataSourceID is defined. What should I do? Thanks

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  • Is there an "opposite" to the null coalescing operator? (…in any language?)

    - by Jay
    null coalescing translates roughly to return x, unless it is null, in which case return y I often need return null if x is null, otherwise return x.y I can use return x == null ? null : x.y; Not bad, but that null in the middle always bothers me -- it seems superfluous. I'd prefer something like return x :: x.y;, where what follows the :: is evaluated only if what precedes it is not null. I see this as almost an opposite to null coalescence, kind of mixed in with a terse, inline null-check, but I'm [almost] certain that there is no such operator in C#. Are there other languages that have such an operator? If so, what is it called? (I know that I can write a method for it in C#; I use return NullOrValue.of(x, () => x.y);, but if you have anything better, I'd like to see that too.)

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  • ASP.NET MVC2 custom rolemanager (webconfig problem)

    - by ile
    Structure of the web: SAMembershipProvider.cs namespace User.Membership { public class SAMembershipProvider : MembershipProvider { #region - Properties - private int NewPasswordLength { get; set; } private string ConnectionString { get; set; } //private MachineKeySection MachineKey { get; set; } //Used when determining encryption key values. public bool enablePasswordReset { get; set; } public bool enablePasswordRetrieval { get; set; } public bool requiresQuestionAndAnswer { get; set; } public bool requiresUniqueEmail { get; set; } public int maxInvalidPasswordAttempts { get; set; } public int passwordAttemptWindow { get; set; } public MembershipPasswordFormat passwordFormat { get; set; } public int minRequiredNonAlphanumericCharacters { get; set; } public int minRequiredPasswordLength { get; set; } public string passwordStrengthRegularExpression { get; set; } public override string ApplicationName { get; set; } // Indicates whether passwords can be retrieved using the provider's GetPassword method. // This property is read-only. public override bool EnablePasswordRetrieval { get { return enablePasswordRetrieval; } } // Indicates whether passwords can be reset using the provider's ResetPassword method. // This property is read-only. public override bool EnablePasswordReset { get { return enablePasswordReset; } } // Indicates whether a password answer must be supplied when calling the provider's GetPassword and ResetPassword methods. // This property is read-only. public override bool RequiresQuestionAndAnswer { get { return requiresQuestionAndAnswer; } } public override int MaxInvalidPasswordAttempts { get { return maxInvalidPasswordAttempts; } } // For a description, see MaxInvalidPasswordAttempts. // This property is read-only. public override int PasswordAttemptWindow { get { return passwordAttemptWindow; } } // Indicates whether each registered user must have a unique e-mail address. // This property is read-only. public override bool RequiresUniqueEmail { get { return requiresUniqueEmail; } } public override MembershipPasswordFormat PasswordFormat { get { return passwordFormat; } } // The minimum number of characters required in a password. // This property is read-only. public override int MinRequiredPasswordLength { get { return minRequiredPasswordLength; } } // The minimum number of non-alphanumeric characters required in a password. // This property is read-only. public override int MinRequiredNonAlphanumericCharacters { get { return minRequiredNonAlphanumericCharacters; } } // A regular expression specifying a pattern to which passwords must conform. // This property is read-only. public override string PasswordStrengthRegularExpression { get { return passwordStrengthRegularExpression; } } #endregion #region - Methods - public override void Initialize(string name, NameValueCollection config) { throw new NotImplementedException(); } public override bool ChangePassword(string username, string oldPassword, string newPassword) { throw new NotImplementedException(); } public override bool ChangePasswordQuestionAndAnswer(string username, string password, string newPasswordQuestion, string newPasswordAnswer) { throw new NotImplementedException(); } // Takes, as input, a user name, password, e-mail address, and other information and adds a new user // to the membership data source. CreateUser returns a MembershipUser object representing the newly // created user. It also accepts an out parameter (in Visual Basic, ByRef) that returns a // MembershipCreateStatus value indicating whether the user was successfully created or, if the user // was not created, the reason why. If the user was not created, CreateUser returns null. // Before creating a new user, CreateUser calls the provider's virtual OnValidatingPassword method to // validate the supplied password. It then creates the user or cancels the action based on the outcome of the call. public override MembershipUser CreateUser(string username, string password, string email, string passwordQuestion, string passwordAnswer, bool isApproved, object providerUserKey, out MembershipCreateStatus status) { throw new NotImplementedException(); } public override bool DeleteUser(string username, bool deleteAllRelatedData) { throw new NotImplementedException(); } public override MembershipUserCollection FindUsersByEmail(string emailToMatch, int pageIndex, int pageSize, out int totalRecords) { throw new NotImplementedException(); } // Returns a MembershipUserCollection containing MembershipUser objects representing users whose user names // match the usernameToMatch input parameter. Wildcard syntax is data source-dependent. MembershipUser objects // in the MembershipUserCollection are sorted by user name. If FindUsersByName finds no matching users, it // returns an empty MembershipUserCollection. // For an explanation of the pageIndex, pageSize, and totalRecords parameters, see the GetAllUsers method. public override MembershipUserCollection FindUsersByName(string usernameToMatch, int pageIndex, int pageSize, out int totalRecords) { throw new NotImplementedException(); } // Returns a MembershipUserCollection containing MembershipUser objects representing all registered users. If // there are no registered users, GetAllUsers returns an empty MembershipUserCollection // The results returned by GetAllUsers are constrained by the pageIndex and pageSize input parameters. pageSize // specifies the maximum number of MembershipUser objects to return. pageIndex identifies which page of results // to return. Page indexes are 0-based. // // GetAllUsers also takes an out parameter (in Visual Basic, ByRef) named totalRecords that, on return, holds // a count of all registered users. public override MembershipUserCollection GetAllUsers(int pageIndex, int pageSize, out int totalRecords) { throw new NotImplementedException(); } // Returns a count of users that are currently online-that is, whose LastActivityDate is greater than the current // date and time minus the value of the membership service's UserIsOnlineTimeWindow property, which can be read // from Membership.UserIsOnlineTimeWindow. UserIsOnlineTimeWindow specifies a time in minutes and is set using // the <membership> element's userIsOnlineTimeWindow attribute. public override int GetNumberOfUsersOnline() { throw new NotImplementedException(); } // Takes, as input, a user name and a password answer and returns that user's password. If the user name is not // valid, GetPassword throws a ProviderException. // Before retrieving a password, GetPassword verifies that EnablePasswordRetrieval is true. If // EnablePasswordRetrieval is false, GetPassword throws a NotSupportedException. If EnablePasswordRetrieval is // true but the password format is hashed, GetPassword throws a ProviderException since hashed passwords cannot, // by definition, be retrieved. A membership provider should also throw a ProviderException from Initialize if // EnablePasswordRetrieval is true but the password format is hashed. // // GetPassword also checks the value of the RequiresQuestionAndAnswer property before retrieving a password. If // RequiresQuestionAndAnswer is true, GetPassword compares the supplied password answer to the stored password // answer and throws a MembershipPasswordException if the two don't match. GetPassword also throws a // MembershipPasswordException if the user whose password is being retrieved is currently locked out. public override string GetPassword(string username, string answer) { throw new NotImplementedException(); } // Takes, as input, a user name or user ID (the method is overloaded) and a Boolean value indicating whether // to update the user's LastActivityDate to show that the user is currently online. GetUser returns a MembershipUser // object representing the specified user. If the user name or user ID is invalid (that is, if it doesn't represent // a registered user) GetUser returns null (Nothing in Visual Basic). public override MembershipUser GetUser(object providerUserKey, bool userIsOnline) { throw new NotImplementedException(); } // Takes, as input, a user name or user ID (the method is overloaded) and a Boolean value indicating whether to // update the user's LastActivityDate to show that the user is currently online. GetUser returns a MembershipUser // object representing the specified user. If the user name or user ID is invalid (that is, if it doesn't represent // a registered user) GetUser returns null (Nothing in Visual Basic). public override MembershipUser GetUser(string username, bool userIsOnline) { throw new NotImplementedException(); } // Takes, as input, an e-mail address and returns the first registered user name whose e-mail address matches the // one supplied. // If it doesn't find a user with a matching e-mail address, GetUserNameByEmail returns an empty string. public override string GetUserNameByEmail(string email) { throw new NotImplementedException(); } // Virtual method called when a password is created. The default implementation in MembershipProvider fires a // ValidatingPassword event, so be sure to call the base class's OnValidatingPassword method if you override // this method. The ValidatingPassword event allows applications to apply additional tests to passwords by // registering event handlers. // A custom provider's CreateUser, ChangePassword, and ResetPassword methods (in short, all methods that record // new passwords) should call this method. protected override void OnValidatingPassword(ValidatePasswordEventArgs e) { base.OnValidatingPassword(e); } // Takes, as input, a user name and a password answer and replaces the user's current password with a new, random // password. ResetPassword then returns the new password. A convenient mechanism for generating a random password // is the Membership.GeneratePassword method. // If the user name is not valid, ResetPassword throws a ProviderException. ResetPassword also checks the value of // the RequiresQuestionAndAnswer property before resetting a password. If RequiresQuestionAndAnswer is true, // ResetPassword compares the supplied password answer to the stored password answer and throws a // MembershipPasswordException if the two don't match. // // Before resetting a password, ResetPassword verifies that EnablePasswordReset is true. If EnablePasswordReset is // false, ResetPassword throws a NotSupportedException. If the user whose password is being changed is currently // locked out, ResetPassword throws a MembershipPasswordException. // // Before resetting a password, ResetPassword calls the provider's virtual OnValidatingPassword method to validate // the new password. It then resets the password or cancels the action based on the outcome of the call. If the new // password is invalid, ResetPassword throws a ProviderException. // // Following a successful password reset, ResetPassword updates the user's LastPasswordChangedDate. public override string ResetPassword(string username, string answer) { throw new NotImplementedException(); } // Unlocks (that is, restores login privileges for) the specified user. UnlockUser returns true if the user is // successfully unlocked. Otherwise, it returns false. If the user is already unlocked, UnlockUser simply returns true. public override bool UnlockUser(string userName) { throw new NotImplementedException(); } // Takes, as input, a MembershipUser object representing a registered user and updates the information stored for // that user in the membership data source. If any of the input submitted in the MembershipUser object is not valid, // UpdateUser throws a ProviderException. // Note that UpdateUser is not obligated to allow all the data that can be encapsulated in a MembershipUser object to // be updated in the data source. public override void UpdateUser(MembershipUser user) { throw new NotImplementedException(); } // Takes, as input, a user name and a password and verifies that they are valid-that is, that the membership data // source contains a matching user name and password. ValidateUser returns true if the user name and password are // valid, if the user is approved (that is, if MembershipUser.IsApproved is true), and if the user isn't currently // locked out. Otherwise, it returns false. // Following a successful validation, ValidateUser updates the user's LastLoginDate and fires an // AuditMembershipAuthenticationSuccess Web event. Following a failed validation, it fires an // // AuditMembershipAuthenticationFailure Web event. public override bool ValidateUser(string username, string password) { throw new NotImplementedException(); //if (string.IsNullOrEmpty(password.Trim())) return false; //string hash = EncryptPassword(password); //User user = _repository.GetByUserName(username); //if (user == null) return false; //if (user.Password == hash) //{ // User = user; // return true; //} //return false; } #endregion /// <summary> /// Procuses an MD5 hash string of the password /// </summary> /// <param name="password">password to hash</param> /// <returns>MD5 Hash string</returns> protected string EncryptPassword(string password) { //we use codepage 1252 because that is what sql server uses byte[] pwdBytes = Encoding.GetEncoding(1252).GetBytes(password); byte[] hashBytes = System.Security.Cryptography.MD5.Create().ComputeHash(pwdBytes); return Encoding.GetEncoding(1252).GetString(hashBytes); } } // End Class } SARoleProvider.cs namespace User.Membership { public class SARoleProvider : RoleProvider { #region - Properties - // The name of the application using the role provider. ApplicationName is used to scope // role data so that applications can choose whether to share role data with other applications. // This property can be read and written. public override string ApplicationName { get; set; } #endregion #region - Methods - public override void Initialize(string name, NameValueCollection config) { throw new NotImplementedException(); } // Takes, as input, a list of user names and a list of role names and adds the specified users to // the specified roles. // AddUsersToRoles throws a ProviderException if any of the user names or role names do not exist. // If any user name or role name is null (Nothing in Visual Basic), AddUsersToRoles throws an // ArgumentNullException. If any user name or role name is an empty string, AddUsersToRoles throws // an ArgumentException. public override void AddUsersToRoles(string[] usernames, string[] roleNames) { throw new NotImplementedException(); } // Takes, as input, a role name and creates the specified role. // CreateRole throws a ProviderException if the role already exists, the role name contains a comma, // or the role name exceeds the maximum length allowed by the data source. public override void CreateRole(string roleName) { throw new NotImplementedException(); } // Takes, as input, a role name and a Boolean value that indicates whether to throw an exception if there // are users currently associated with the role, and then deletes the specified role. // If the throwOnPopulatedRole input parameter is true and the specified role has one or more members, // DeleteRole throws a ProviderException and does not delete the role. If throwOnPopulatedRole is false, // DeleteRole deletes the role whether it is empty or not. // // When DeleteRole deletes a role and there are users assigned to that role, it also removes users from the role. public override bool DeleteRole(string roleName, bool throwOnPopulatedRole) { throw new NotImplementedException(); } // Takes, as input, a search pattern and a role name and returns a list of users belonging to the specified role // whose user names match the pattern. Wildcard syntax is data-source-dependent and may vary from provider to // provider. User names are returned in alphabetical order. // If the search finds no matches, FindUsersInRole returns an empty string array (a string array with no elements). // If the role does not exist, FindUsersInRole throws a ProviderException. public override string[] FindUsersInRole(string roleName, string usernameToMatch) { throw new NotImplementedException(); } // Returns the names of all existing roles. If no roles exist, GetAllRoles returns an empty string array (a string // array with no elements). public override string[] GetAllRoles() { throw new NotImplementedException(); } // Takes, as input, a user name and returns the names of the roles to which the user belongs. // If the user is not assigned to any roles, GetRolesForUser returns an empty string array // (a string array with no elements). If the user name does not exist, GetRolesForUser throws a // ProviderException. public override string[] GetRolesForUser(string username) { throw new NotImplementedException(); //User user = _repository.GetByUserName(username); //string[] roles = new string[user.Role.Rights.Count + 1]; //roles[0] = user.Role.Description; //int idx = 0; //foreach (Right right in user.Role.Rights) // roles[++idx] = right.Description; //return roles; } public override string[] GetUsersInRole(string roleName) { throw new NotImplementedException(); } // Takes, as input, a role name and returns the names of all users assigned to that role. // If no users are associated with the specified role, GetUserInRole returns an empty string array (a string array with // no elements). If the role does not exist, GetUsersInRole throws a ProviderException. public override bool IsUserInRole(string username, string roleName) { throw new NotImplementedException(); //User user = _repository.GetByUserName(username); //if (user != null) // return user.IsInRole(roleName); //else // return false; } // Takes, as input, a list of user names and a list of role names and removes the specified users from the specified roles. // RemoveUsersFromRoles throws a ProviderException if any of the users or roles do not exist, or if any user specified // in the call does not belong to the role from which he or she is being removed. public override void RemoveUsersFromRoles(string[] usernames, string[] roleNames) { throw new NotImplementedException(); } // Takes, as input, a role name and determines whether the role exists. public override bool RoleExists(string roleName) { throw new NotImplementedException(); } #endregion } // End Class } From Web.config: <membership defaultProvider="SAMembershipProvider" userIsOnlineTimeWindow="15"> <providers> <clear/> <add name="SAMembershipProvider" type="User.Membership.SAMembershipProvider, User" /> </providers> </membership> <roleManager defaultProvider="SARoleProvider" enabled="true" cacheRolesInCookie="true"> <providers> <clear/> <add name="SARoleProvider" type="User.Membership.SARoleProvider" /> </providers> </roleManager> When running project, I get following error: Server Error in '/' Application. Configuration Error Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately. Parser Error Message: The method or operation is not implemented. Source Error: Line 71: <providers> Line 72: <clear/> Line 73: <add name="SARoleProvider" type="User.Membership.SARoleProvider" /> Line 74: </providers> Line 75: </roleManager> I tried: <add name="SARoleProvider" type="User.Membership.SARoleProvider, User" /> and <add name="SARoleProvider" type="User.Membership.SARoleProvider, SARoleProvider" /> and <add name="SARoleProvider" type="User.Membership.SARoleProvider, User.Membership" /> but none works Any idea what's wrong here? Thanks, Ile

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  • code optimization; switch versus if's

    - by KaiserJohaan
    Hello, I have a question about whether to use 'case' or 'ifs' in a function that gets called quite alot. Here's the following as it is now, in 'ifs'; the code is self-explanatory: int identifyMsg(char* textbuff) { if (!strcmp(textbuff,"text")) { return 1; } if (!strcmp(textbuff,"name")) { return 2; } if (!strcmp(textbuff,"list")) { return 3; } if (!strcmp(textbuff,"remv")) { return 4; } if (!strcmp(textbuff,"ipad")) { return 5; } if (!strcmp(textbuff,"iprm")) { return 6; } return 0; } My question is: Would a switch perform better? I know if using ifs, I can place the most likely options at the top.

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  • document.getElementById in toString

    - by KooiInc
    edit Found my answers here. Bottom line: toString/valueOf can only return primitive types. So here the lack of native getters in javascript shows, I suppose. I would like to use the following simple function in an elementwrapper: function ElGetter(id){ var id = id; return { set: function(nwid){id = nwid;}, toString: function(){return document.getElementById(id);}, valueOf: function(){return document.getElementById(id);} }; } var myEl = ElGetter('myId'); console.log(myEl.innerHTML); //=> undefined But I can't get it to work. Is it a DOM/javascript restriction or am I missing something? Normally it works, as in: function Tester(){ var x = 1; return { toString: function(){return x}, valueOf: function(){return x} } } var myTest = Tester(); console.log(myTest); //=> 1

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  • In PHP is faster to get a value from an if statement or from an array?

    - by Vittorio Vittori
    Maybe this is a stupid question but what is faster? <?php function getCss1 ($id = 0) { if ($id == 1) { return 'red'; } else if ($id == 2) { return 'yellow'; } else if ($id == 3) { return 'green'; } else if ($id == 4) { return 'blue'; } else if ($id == 5) { return 'orange'; } else { return 'grey'; } } function getCss2 ($id = 0) { $css[] = 'grey'; $css[] = 'red'; $css[] = 'yellow'; $css[] = 'green'; $css[] = 'blue'; $css[] = 'orange'; return $css[$id]; } echo getCss1(3); echo getCss2(3); ?> I suspect is faster the if statement but I prefere to ask!

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  • Unnecessary 'else' statement

    - by Vitalii Fedorenko
    As you know, in Eclipse you can turn on "Unnecessary 'else' statement" check that will trigger on if-then-else with premature return. And, from my experience, there are two most possible situations when use such statement: 1) Pre-check: if (validate(arg1)) { return false; } doLotOfStuff(); 2) Post-check: doLotOfStuff(); if (condition) { return foo; } else { return bar; } In the second case, if the trigger is on, Eclipse will suggest you to change the code to: doLotOfStuff(); if (condition) { return foo; } return bar; However, I think that the return with else statement is more readable as it is like direct mapping of business logic. So I am curios if this "Unnecessary 'else' statement" code convention is widespread or else statement is more preferable?

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  • sorting a list of objects by value php

    - by Mike
    I have a list of objects: class Beer { var $name; var $id; var $style; var $brewery; var $rate; function getName() { return $this->name; } function getID() { return $this->id; } function getStyle() { return $this->style; } function getBrewery() { return $this->brewery; } function getRate() { return $this->rate; } } After doing some research online on how to accomplish this, this is my code: usort($localBeersList, "cmp"); function cmp($a, $b) { if ($a->getRate() == $b->getRate()) { return 0; } return ($a->getRate() < $b->getRate()) ? -1 : 1; } If I try and output my list after this I do not get anything.

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  • python function that returns a function from list of functions

    - by thkang
    I want to make following function: 1)input is a number. 2)functions are indexed, return a function whose index matches given number here's what I came up with: def foo_selector(whatfoo): def foo1(): return def foo2(): return def foo3(): return ... def foo999(): return #something like return foo[whatfoo] the problem is, how can I index the functions (foo#)? I can see functions foo1 to foo999 by dir(). however, dir() returns name of such functions, not the functions themselves. In the example, those foo-functions aren't doing anything. However in my program they perform different tasks and I can't automatically generate them. I write them myself, and have to return them by their name.

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  • Is correct name enough to make it happen?

    - by Knowing me knowing you
    Guys, I've just dipped in to limits.h by MS. I tried to check what's the return type for max() fnc and to my surprise I see something like this: // TEMPLATE CLASS numeric_limits template<class _Ty> class numeric_limits : public _Num_base { // numeric limits for arbitrary type _Ty (say little or nothing) public: static _Ty (__CRTDECL min)() _THROW0() { // return minimum value return (_Ty(0)); } static _Ty (__CRTDECL max)() _THROW0() { // return maximum value return (_Ty(0));//EXACTLY THE SAME WHAT IN min<<------------------ } //... other stuff }; so how is it possiple that in both min and max return does exactly the same? So does it mean if I would write makeSanwich() return (_Ty(0)) it would make a sandwich for me? How is it possible that having this same code just fnc names different we are getting different results?

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