Search Results

Search found 36506 results on 1461 pages for 'unsigned long long int'.

Page 319/1461 | < Previous Page | 315 316 317 318 319 320 321 322 323 324 325 326  | Next Page >

• C code Error: free(): invalid next size (fast):

  - by user1436057

  I got an error from my code, but I'm not sure where to fix it. Here's the explanation of what my code does: I'm writing some code that will read an input file and store each line as an object (char type) in an array. The first line of the input file is a number. This number tells me how many lines that I should read and store in the array. Here's my code: int main(int argc, char *argv[]){ FILE *fp; char **path; int num, i; ... /*after reading the first line and store the number value in num*/ path = malloc(num *sizeof(char)); i=0; while (!feof(fp)) { char buffer[500]; int length = 0; for (ch = fgetc(fp); ch != EOF && ch != '\n'; ch = fgetc(fp)) { buffer[length++] = ch; } if(ch == '\n' && ch!= EOF){ buffer[length] = '\0'; path[i] = malloc(strlen(buffer)+1); strcpy(path[i], buffer); i++; } } ... free(path); } After running the code, I get this *** glibc detected *** free(): invalid next size (fast): I have searched around and know this is malloc/free error, but I don't exactly know to fix it. Any help would be great. Thanks!

  Read the article

• Operator Overloading << in c++

  - by thlgood

  I'm a fresh man in C++. I write this simple program to practice Overlaoding. This is my code: #include <iostream> #include <string> using namespace std; class sex_t { private: char __sex__; public: sex_t(char sex_v = 'M'):__sex__(sex_v) { if (sex_v != 'M' && sex_v != 'F') { cerr << "Sex type error!" << sex_v << endl; __sex__ = 'M'; } } const ostream& operator << (const ostream& stream) { if (__sex__ == 'M') cout << "Male"; else cout << "Female"; return stream; } }; int main(int argc, char *argv[]) { sex_t me('M'); cout << me << endl; return 0; } When I compiler it, It print a lots of error message: The error message was in a mess. It's too hard for me to found useful message sex.cpp: ???‘int main(int, char**)’?: sex.cpp:32:10: ??: ‘operator<<’?‘std::cout << me’????? sex.cpp:32:10: ??: ???: /usr/include/c++/4.6/ostream:110:7: ??: std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(std::basic_ostre

  Read the article

• insertvalue function in stack class is not calling when pointing by smartpointer class? please expai

  - by user323422

  template< class Type > class cStack { Type *m_array; int m_Top; int m_Size; public:cStack(); cStack(const Type&); cStack(const cStack<Type> &); bool Is_Full(); bool Is_Empty(); void InsertValue(const Type&); void RemeoveValue(); ~cStack(); }; template< class Type > class Smartpointer { cStack<Type> *sPtr; public: Smartpointer(); Smartpointer(const Type&); Type* operator->(); Type& operator*(); }; int main() { Smartpointer<int> sptr(1); sptr->InsertValue(2);//its not calling insertvalue } }

  Read the article

• Calculating percent "x/y * 100" always results in 0?

  - by Patrick Beninga

  In my assignment i have to make a simple version of Craps, for some reason the percentage assignments always produce 0 even when both variables are non 0, here is the code. import java.util.Random; Header, note the variables public class Craps { private int die1, die2,myRoll ,myBet,point,myWins,myLosses; private double winPercent,lossPercent; private Random r = new Random(); Just rolls two dies and produces their some. public int roll(){ die1 = r.nextInt(6)+1; die2 = r.nextInt(6)+1; return(die1 + die2); } The Play method, this just loops through the game. public void play(){ myRoll = roll(); point = 0; if(myRoll == 2 ||myRoll == 3 || myRoll == 12){ System.out.println("You lose!"); myLosses++; }else if(myRoll == 7 || myRoll == 11){ System.out.println("You win!"); myWins++; }else{ point = myRoll; do { myRoll = roll(); }while(myRoll != 7 && myRoll != point); if(myRoll == point){ System.out.println("You win!"); myWins++; }else{ System.out.println("You lose!"); myLosses++; } } } This is where the bug is, this is the tester method. public void tester(int howMany){ int i = 0; while(i < howMany){ play(); i++; } bug is right here in these assignments statements winPercent = myWins/i * 100; lossPercent = myLosses/i* 100; System.out.println("program ran "+i+" times "+winPercent+"% wins "+ lossPercent+"% losses with "+myWins+" wins and "+myLosses+" losses"); } }

  Read the article

• How to make a multi vector in C++

  - by Bob Dealio

  I was wondering why can't I have a multi vectors in C ++ /please take a look at this example, it's not working though. there are only two parts to the code, foo function to manipulate the vector and the main function to echo them. typedef vector< vector<double> > MyVec; MyVec foo() { MyVec v; for (int index=0; index < 2; index ++) { for (int j=0; j<5; j++) { v[index][j]; } } return v; } int main () { MyVec z = foo(); for (int i = 0; i < z.size(); i++) { cout << z[i][1]; } return 0; }

  Read the article

• C++ Template Classes and Copy Construction

  - by themoondothshine

  Is there any way I can construct an new object from the given object if the template parameters of both objects are identical at run-time? For example: I have a template class with the declaration: template<typename _Type1, typename _Type2> class Object; Next, I have two instantiations of the template: template class Object<char, int>; template class Object<wchar_t, wint_t>; Now, I want to write a member function such as: template<typename _Type1, typename _Type2> Object<char, int> Object<_Type1, _Type2>::toCharObject() { if(__gnu_cxx::__are_same<_Type1, char>::__value) return *this; else { //Perform some kind of conversion and return an Object<char, int> } } I have tried a couple of techniques, such as using __gnu_cxx::__enable_if<__gnu_cxx::__are_same<_Type1, char>::__value, _Type1>::__type in a copy constructor for the Oject class, but I keep running into the error: error: conversion from ‘Object<wchar_t, wint_t>’ to non-scalar type ‘Object<char, int>’ requested Is there no way I can do this? Any help will be greatly appreciated!

  Read the article

• how to pass arraylist as parameter to another screen

  - by user2867267

  how to pass arraylist as parameter to another activity in my condition im not using listview and checkif arraylist contain single element then pass that arrraylist as parameter toanother screen see thisline Category_name.get(position).toString()); how i remove position?? how to passs arraylist parameter toanother activity static ArrayList<Long> Menu_ID = new ArrayList<Long>(); static ArrayList<String> Category_name = new ArrayList<String>(); JSONArray school = json2.getJSONArray("data"); for (int i = 0; i < school.length(); i++) { JSONObject object = school.getJSONObject(i); Category_ID.add((long) i); Menu_ID.add(Long.parseLong(object.getString("menu_id"))); Category_name.add(object.getString("menu_title")); } Intent iMenuList = new Intent(MenuGroup.this, thirdstep.class); menuidvalue=""; menuidvalue =( Menu_ID.get(position)).toString(); iMenuList.putExtra("Menu_ID",menuidvalue); iMenuList.putExtra("menu_group", Category_name.get(position).toString()); startActivity(iMenuList);

  Read the article

• sorting char* arrays

  - by skazhy

  Hi! I have a datastructure struct record { char cont[bufferSize]; record *next; }; When I add new records to this structure, I want them to be sorted alphabetically. I made this function, that adds record in the right place (by alphabet) in the linked list: record *start=NULL, *p, *x; void recAdd(char*temp) { p = new record; temp[strlen(temp)] = '\0'; for (int j=0;j<bufferSize;j++) p->cont[j] = temp[j]; if (start==NULL) start=p; else { x=start; int c=0; while (recComp(x->cont,p->cont) <= 0 && x->next != NULL) { x=x->next; c++; } if (c == 0) { p->next=start; start=p; } else { x=start; for (int i=0;i<c;i++) x=x->next; p->next=x->next; x->next=p; } } for (int j=0;j<bufferSize;j++) temp[j] = NULL; }; But somehow it doesn't sort things right. What is wrong with my function?

  Read the article

• c++ Multiple Inheritance - Compiler modifying my pointers

  - by Bob

  If I run the following code, I get different addresses printed. Why? class Base1 { int x; }; class Base2 { int y; }; class Derived : public Base1, public Base2 { }; union U { Base2* b; Derived* d; U(Base2* b2) : b(b) {} }; int main() { Derived* d = new Derived; cout << d << "\n"; cout << U(d).d << "\n"; return 0; } Even more fun is if you repeatedly go in and out of the union the address keeps incrementing by 4, like this int main() { Derived* d = new Derived; cout << d << "\n"; d = U(d).d; cout << d << "\n"; d = U(d).d; cout << d << "\n"; return 0; } If the union is modified like this, then the problem goes away union U { void* v; Base2* b; Derived* d; U(void* v) : v(v) {} }; Also, if either base class is made empty, the problem goes away. Is this a compiler bug? I want it to leave my pointers the hell alone.

  Read the article

• Having an issue with the "this" modifier...

  - by user344246

  I have this method in City class. It should create a new city based on the object which the method is applied to: public City newCity(string newCityName, int dX, int dY) { City c=new City(this); //based on a constructor : City(City c){} c.CityName=newCityName; c.NoOfNeighborhoods=1; c.NumOfResidents=0; c.CityCenter.Move(dX,dY); return c; } CityCenter is of type "Point" which has two fields - x,y. the Move method in Point class is ment to change the CityCenter location. It looks like this: public void Move(int dX, int dY) { this.X = x + dX; this.Y = y + dY; } What happens is that the new object,c and the existing City object are both changed. I think that "this" modifier works on the existing object too... How can I take advantage of the Move method without causing this behavior? Note: this is a closed API, so I can only add private methods to the project.

  Read the article

• c# How to get string from byte?

  - by Kade

  I have a form-console application which does a TCP socket connections for send and receive. I need help getting the following response to STRING. The following code does write the RESPONSE to the console, but i also want to byte[] b = new byte[100]; int k = s.Receive(b); Console.WriteLine("Recieved..."); for (int i = 0; i < k; i++) Console.Write(Convert.ToChar(b[i])); ASCIIEncoding asen = new ASCIIEncoding(); s.Send(asen.GetBytes("RECEIVED :")); i want to get something like String GETSTRING; byte[] b = new byte[100]; int k = s.Receive(b); Console.WriteLine("Recieved..."); for (int i = 0; i < k; i++) Console.Write(Convert.ToChar(b[i])); GETSTRING = *WHATEVER RESPONSE RECEIVED ABOVE* ASCIIEncoding asen = new ASCIIEncoding(); s.Send(asen.GetBytes("RECEIVED :"));

  Read the article

• Load image blurred Android

  - by Mira

  I'm trying to create a map for a game through an image, where each black pixel is equivalent to a wall, and yellow to flowers(1) and green grass(0) so far i had this image (50x50): http://i.imgur.com/Ydj9Cp2.png the problem here seems to be that, when i read the image on my code, it get's scaled up to 100x100, even tough i have it on the raw folder. I can't let it scale up or down because that will put noise and blur on the image and then the map won't be readable. here i have my code: (...) Bitmap tab=BitmapFactory.decodeResource(resources, com.example.lolitos2.R.raw.mappixel); //tab=Bitmap.createScaledBitmap(tab, 50, 50, false); Log.e("w", tab.getWidth()+"."+tab.getHeight()); for (int i = 0; i < tab.getWidth(); i++) { for (int j = 0; j < tab.getHeight(); j++) { int x = j; int y = i; switch (tab.getPixel(x, y)) { // se o é uma parede case Color.BLACK: getParedes()[x][y] = new Parede(x, y); break; case Color.GREEN: fundo.add(new Passivo(x,y,0)); break; default: fundo.add(new Passivo(x,y,1)); } } } How can i read my image Map without rescaling it?

  Read the article

• How to ensure I get the picture is complete? (in java)

  - by Zenofo

  i using below code to get a picture from URL: URL url=new URL("http://www.google.com/images/logos/ps_logo2.png"); InputStream in=url.openStream(); ByteArrayOutputStream tmpOut = new ByteArrayOutputStream(); byte[] buf = new byte[512]; int len; while (true) { len = in.read(buf); if (len == -1) { break; } tmpOut.write(buf, 0, len); } tmpOut.close(); byte[] picture=tmpOut.toByteArray(); System.out.println(picture.length); this code is okay,but my internet connect is very very bad, so ,I maybe get a broken picture like this: How can I ensure the picture file is complete ? I think you can add this code to try and test this: if (len == -1) { change to if (len == -1 || (int)(Math.random()*100)==1 ) { full test code: URL url=new URL("http://www.google.com/images/logos/ps_logo2.png"); InputStream in=url.openStream(); ByteArrayOutputStream tmpOut = new ByteArrayOutputStream(); byte[] buf = new byte[512]; int len; while (true) { len = in.read(buf); if (len == -1 || (int)(Math.random()*100)==1 ) { break; } tmpOut.write(buf, 0, len); } tmpOut.close(); byte[] picture =tmpOut.toByteArray(); System.out.println(picture.length); thanks for help :)

  Read the article

• Associate two sets of values

  - by PJW

  I have the following code - public static int GetViewLevel(string viewLevelDesc) { try { switch (viewLevelDesc) { case "All": return 0; case "Office": return 10; case "Manager": return 50; default: throw new Exception("Invalid View Level Description"); } } catch (Exception eX) { throw new Exception("Action: GetViewLevel()" + Environment.NewLine + eX.Message); } } public static string GetViewLevelDescription(int viewLevel) { try { switch (viewLevel) { case 0: return "All"; case 10: return "Office"; case 50: return "Manager"; default: throw new Exception("Invalid View Level Description"); } } catch (Exception eX) { throw new Exception("Action: GetViewLevelDescription()" + Environment.NewLine + eX.Message); } } The two static Methods enable me to either get an int ViewLevel from a string ViewLevelDesc or vice versa. I'm sure the way I have done this is far more cumbersome than it needs to be, and I'm looking for some advice how to achieve the same objective but more concisely. The list of int / string pairs will increase significantly. The ones in the above code are just the first three I intend to use.

  Read the article

• MySQL Check and compare and if necessary create data.

  - by user2979677

  Hello I have three different tables Talk ID type_id YEAR NUM NUM_LETTER DATE series_id TALK speaker_id SCRIPREF DONE DOUBLE_SID DOUBLE_TYP LOCAL_CODE MISSING RESTRICTED WHY_RESTRI SR_S_1 SR_E_1 BCV_1 SR_S_2 SR_E_2 BCV_2 SR_S_3 SR_E_3 BCV_3 SR_S_4 SR_E_4 BCV_4 QTY_IV organisation_id recommended topic_id thumbnail mp3_file_size duration version Product_component id product_id talk_id position version Product id created product_type_id last_modified last_modified_by num_sold current_stock min_stock max_stock comment organisation_id series_id name subscription_type_id recipient_id discount_start discount_amount discount_desc discount_finish discount_percent voucher_amount audio_points talk_id price_override product_desc instant_download_status_id downloads instant_downloads promote_start promote_finish promote_desc restricted from_tape discontinued discontinued_reason discontinued_date external_url version I want to create a procedure that will check if select the id from talk and compare it with the id of product to see if there is a product id in the table and if there isn't then create it however my problem is that my tables talk and product can't talk, as id in talk is related to talk_id in product_component and id in product is related to product_id in product_component. Are there any ways for this to be done? I tried this, CREATE DEFINER=`sthelensmedia`@`localhost` PROCEDURE `CreateSingleCDProducts`() BEGIN DECLARE t_id INT; DECLARE t_restricted BOOLEAN; DECLARE t_talk CHAR(255); DECLARE t_series_id INT; DECLARE p_id INT; DECLARE done INT DEFAULT 0; DECLARE cur1 CURSOR FOR SELECT id,restricted,talk,series_id FROM talk WHERE organisation_id=2; DECLARE CONTINUE HANDLER FOR NOT FOUND SET done=1; UPDATE product SET restricted=TRUE WHERE product_type_id=3; OPEN cur1; create_loop: LOOP FETCH cur1 INTO t_id, t_restricted, t_talk, t_series_id; IF done=1 THEN LEAVE create_loop; END IF; INSERT INTO product (created,product_type_id,last_modified,organisation_id,series_id,name,restricted) VALUES (NOW(),3,NOW(),2,t_series_id,t_talk,t_restricted); SELECT LAST_INSERT_ID() INTO p_id; INSERT INTO product_component (product_id,talk_id,position) VALUES (p_id,t_id,0); END LOOP create_loop; CLOSE cur1; END Just wondering if anyone could help me.

  Read the article

• how to start activity of the positive button?

  - by Wisnuardi

  when I click an item in maps, it will appears positive button that reads "Route to". Question, how do I start activity from that positive button? I also use like this, dialog.setPositiveButton("Tampilkan Rute", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int Button) { Intent i = new Intent(this, Rute.class); startActivity(i); } }); to startactivity into Rute class but it always say "remove argument to match intent()" then I don't know what to do. here is my code @Override protected boolean onTap(int index) { OverlayItem item = items.get(0); AlertDialog.Builder dialog = new AlertDialog.Builder(mContext); dialog.setTitle(item.getTitle()); dialog.setMessage(item.getSnippet()); dialog.setPositiveButton("Tampilkan Rute", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int Button) { Intent i = new Intent(this, Rute.class); startActivity(i); } }); dialog.setNegativeButton("Kembali", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int Button) { dialog.cancel(); } }); dialog.show(); return true; } Any suggestions will be greatly appreciated. Thank's i'm sorry if my english is bad :(

  Read the article

• displaying a dialog using an activity?

  - by ricardo123

  what am i doing wrong here or what do i need to add? package dialog.com; import android.app.Activity; import android.app.AlertDialog; import android.content.DialogInterface; import android.app.Dialog; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.Toast; public class Dialog extends Activity { CharSequence [] items = { "google", "apple", "microsoft" }; boolean [] itemschecked = new boolean [items.length]; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); Button btn = (Button) findViewById(R.id.btn_dialog); btn.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { showDialog(0); } }); } @Override protected Dialog onCreateDialog(int id) { switch(id) { case 0: return new AlertDialog.Builder(this) .setIcon(R.drawable.icon) .setTitle("This is a Dialog with some simple text...") .setPositiveButton("ok", new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int whichbutton) { Toast.makeText(getBaseContext(), "OK Clicked!", Toast.LENGTH_SHORT).show(); } }); .setNegativeButton("cancel",new DialogInterface.OnclickListener() { public void onClick(DialogInterface dialog, int whichButton) {Toast.makeText(getBaseContext(), "cancel clicked!", Toast.LENGTH_SHORT).show(); } }); .setMultiChoiceItems(itemschecked, new DialogInterface.OnMultiChoiceClickListener() { @Override public void onClick(dialoginterface dialog, int which, boolean isChecked) { Toast.makeText(getBaseContext(), items[which] + (isChecked ? " checked!": "unchecked!"), Toast.LENGTH_SHORT).show(); } } ) .create(); } return null: }}}

  Read the article

• Populating a color array with every 8th pixel in an image. C#

  - by Piper

  I have an image that is 512x280 pixels. I want to populate a 64x35 array with every 8th pixel in the matrix. Here is what I have right now: Color[,] imgArray = new Color[b.Width, b.Height]; for (int y = 0; y < 35; y++) { for (int x = 0; x < 64; x++) { imgArray[x, y] = b.GetPixel(x, y); } } But that will get just the top corner of the image. How would I change the loop so it grabs every 8th pixel to fill the array with? edit: I think I may have gotten it. Can someone read this and assure me that it is correct? Color[,] imgArray = new Color[64, 35]; for (int y = 0; y < 280; y+=8) { for (int x = 0; x < 512; x+=8) { imgArray[x, y] = b.GetPixel(x, y); } }

  Read the article

• # how to split the column values using stored procedure

  - by user1444281

  I have two tables table 1 is SELECT * FROM dbo.TBL_WD_WEB_DECK WD_ID WD_TITLE ------------------ 1 2 and data in 2nd table is WS_ID WS_WEBPAGE_ID WS_SPONSORS_ID WS_STATUS ----------------------------------------------------- 1 1 1,2,3,4 Y I wrote the following stored procedure to insert the data into both the tables catching the identity of main table dbo.TBL_WD_WEB_DECK. WD_ID is related with WS_WEBPAGE_ID. I wrote the cursor in update action to split the WS_SPONSORS_ID column calling the split function in the cursor. But it is not working. The stored procedure is: ALTER procedure [dbo].[SP_Example_SPLIT] ( @action char(1), @wd_id int out, @wd_title varchar(50), @ws_webpage_id int, @ws_sponsors_id varchar(250), @ws_status char(1) ) as begin set nocount on IF (@action = 'A') BEGIN INSERT INTO dbo.TBL_WD_WEB_DECK(WD_TITLE)VALUES(@WD_TITLE) DECLARE @X INT SET @X = @@IDENTITY INSERT INTO dbo.TBL_WD_SPONSORS(WS_WEBPAGE_ID,WS_SPONSORS_ID,WS_STATUS) VALUES (@ws_webpage_id,@ws_sponsors_id,@ws_status) END ELSE IF (@action = 'U') BEGIN UPDATE dbo.TBL_WD_WEB_DECK SET WD_TITLE = @wd_title WHERE WD_ID = @WD_ID UPDATE dbo.TBL_WD_SPONSORS SET WS_STATUS = 'N' where WS_SPONSORS_ID not in (@ws_sponsors_id) and ws_webpage_id = @wd_id BEGIN /* Declaring Cursor to split the value in ws_sponsors_id column */ Declare @var int Declare splt cursor for /* used the split function and calling the parameter in that split function */ select * from iter_simple_intlist_to_tbl(@WS_SPONSORS_ID) OPEN splt FETCH NEXT FROM splt INTO @var WHILE (@@FETCH_STATUS = 0) begin if not exists(select * from dbo.TBL_WD_SPONSORS where WS_WEBPAGE_ID = @wd_id and WS_SPONSORS_ID = @var) begin insert into dbo.TBL_WD_SPONSORS (WS_WEBPAGE_ID,WS_SPONSORS_ID) values(@wd_id,@var) end end CLOSE SPONSOR DEALLOCATE SPONSOR END END END The result I want is if I insert the data in WD_ID and IN WS_SPONSORS_ID column the data in the WS_SPONSORS_ID column should split and I need to compare it with WD_ID. The result I need is: WD_ID WD_TITLE --------------------- 1 TEST 2 TEST1 3 WS_ID WS_WEBPAGE_ID WS_SPONSORS_ID WS_STATUS -------------------------------------------------------- 1 1 1 Y 2 1 2 N 3 1 3 Y If I pass the string in WS_SPONSORS_ID as 1,2,3 it has to split like the above. Can you help?

  Read the article

• getting duplicate array output - java

  - by dowln

  Hello, Can someone could be kind and help me out here. Thanks in advance... My code below outputs the string as duplicates. I don't want to use Sets or ArrayList. I am using java.util.Random. I am trying to write a code that checks if string has already been randomly outputted and if it does, then it won't display. Where I am going wrong and how do I fix this. public class Worldcountries { private static Random nums = new Random(); private static String[] countries = { "America", "Candada", "Chile", "Argentina" }; public static int Dice() { return (generator.nums.nextInt(6) + 1); } public String randomCounties() { String aTemp = " "; int numOfTimes = Dice(); int dup = 0; for(int i=0 ; i<numOfTimes; i++) { // I think it's in the if statement where I am going wrong. if (!countries[i].equals(countries[i])) { i = i + 1; } else { dup--; } // and maybe here aTemp = aTemp + countries[nums.nextInt(countries.length)]; aTemp = aTemp + ","; } return aTemp; } } So the output I am getting (randomly) is, "America, America, Chile" when it should be "America, Chile".

  Read the article

• Generating an identifier for objects so that they can be added to a hashtable I have created

  - by dukenukem

  I have a hashtable base class and I am creating different type of hashtable by deriving from it. I only allow it to accept objects that implement my IHashable interface.For example - class LinearProbingHashTable<T> : HashTableBase<T> where T: IHashable { ... ... ... } interface IHashable { /** * Every IHashable implementation should provide an indentfying value for use in generating a hash key. */ int getIdentifier(); } class Car : IHashable { public String Make { get; set; } public String Model { get; set; } public String Color { get; set; } public int Year { get; set; } public int getIdentifier() { /// ??? } } Can anyone suggest a good method for generating an identifier for the car that can be used by the hash function to place it in the hash table? I am actually really looking for a general purpose solution to generating an id for any given class. I would like to have a base class for all classes, HashableObject, that implements IHashable and its getIdentifier method. So then I could just derive from HashableObject which would automatically provide an identifier for any instances. Which means I wouldn't have to write a different getIdentifier method for every object I add to the hashtable. public class HashableObject : IHashable { public int getIdentifier() { // Looking for code here that would generate an id for any object... } } public class Dog : HashableObject { // Dont need to implement getIdentifier because the parent class does it for me }

  Read the article

• delay loop output in C++

  - by itachisxeyes

  I have a while loop that runs in a do while loop. I need the while loop to run exactly every second no faster no slower. but i'm not sure how i would do that. this is the loop, off in its own function. I have heard of the sleep() function but I also have heard that it is not very accurate. int min5() { int second = 00; int minute = 0; const int ZERO = 00; do{ while (second <= 59){ if(minute == 5) break; second += 1; if(second == 60) minute += 1; if(second == 60) second = ZERO; if(second < 60) cout << "Current Time> "<< minute <<" : "<< second <<" \n"; } } while (minute <= 5); }

  Read the article

• Java - Display % of upload done

  - by tr-raziel

  I have a java applet for uploading files to server. I want to display the % of data sent but when I use ObjectOutputStream.write() it just writes to the buffer, does not wait until the data has actually been sent. How can I achieve this. Perhaps I need to use thread synchronization or something. Any clues would be most helpful. This is the code I'm using right now: try{ for(File file : ficheiros){ FileInputStream stream = new FileInputStream (file); int bytesRead1 = 0;; int off1 = 0; int len1 = 100000; if(file.length() < 100000) len1 = new Long(file.length()).intValue(); byte[] bytes1 = new byte[len1]; while (off1 < file.length()) { bytes1 = new byte[len1]; if((file.length() - off1) < len1){ len1 = (new Long(file.length()).intValue() - off1); bytes1 = new byte[len1]; } if((bytesRead1 = stream.read(bytes1)) != -1){ //I want this to block until all data has been sent outputToServlet.write(bytes1, 0, bytesRead1 ); System.out.println("off1: " + off1); off1 = off1 + len1; outputToServlet.flush(); } sent += len1; if(sent>totalLength) sent = (int)totalLength; updateFeedback(sent,totalLength,false);//calls method to display % } updateFeedback(-1,-1,true); } }catch(Exception e){ e.printStackTrace(); } Thanks

  Read the article

• Gnome Do not Launching

  - by PyRulez

  When I try running gnome do, I get this. chris@Chris-Ubuntu-Laptop:~$ gnome-do pgrep: invalid user name: -u and it is not writable Trying sudo: chris@Chris-Ubuntu-Laptop:~$ sudo gnome-do [NetworkService] Could not initialize Network Manager dbus: Unable to open the session message bus. [Error 17:54:30.122] [SystemService] Could not initialize dbus: Unable to open the session message bus. (Do:2401): Wnck-CRITICAL **: wnck_set_client_type got called multiple times. (Do:2401): libdo-WARNING **: Binding '<Super>space' failed! [Error 17:54:30.649] [AbstractKeyBindingService] Key "" is already mapped. Tomboy.NotesItemSource "Tomboy Notes" encountered an error in UpdateItems: System.TypeInitializationException: An exception was thrown by the type initializer for Tomboy.TomboyDBus ---> System.Exception: Unable to open the session message bus. ---> System.ArgumentNullException: Argument cannot be null. Parameter name: address at NDesk.DBus.Bus.Open (System.String address) [0x00000] in <filename unknown>:0 at NDesk.DBus.Bus.get_Session () [0x00000] in <filename unknown>:0 --- End of inner exception stack trace --- at NDesk.DBus.Bus.get_Session () [0x00000] in <filename unknown>:0 at Tomboy.TomboyDBus..cctor () [0x00000] in <filename unknown>:0 --- End of inner exception stack trace --- at Tomboy.NotesItemSource.UpdateItems () [0x00000] in <filename unknown>:0 at Do.Universe.Safe.SafeItemSource.UpdateItems () [0x00000] in <filename unknown>:0 . Firefox.PlacesItemSource "Firefox Places" encountered an error in UpdateItems: System.InvalidCastException: Cannot cast from source type to destination type. at Mono.Data.Sqlite.SqliteDataReader.VerifyType (Int32 i, DbType typ) [0x00000] in <filename unknown>:0 at Mono.Data.Sqlite.SqliteDataReader.GetString (Int32 i) [0x00000] in <filename unknown>:0 at Firefox.PlacesItemSource+<LoadPlaceItems>c__Iterator3.MoveNext () [0x00000] in <filename unknown>:0 at System.Collections.Generic.List`1[Firefox.PlaceItem].AddEnumerable (IEnumerable`1 enumerable) [0x00000] in <filename unknown>:0 at System.Collections.Generic.List`1[Firefox.PlaceItem]..ctor (IEnumerable`1 collection) [0x00000] in <filename unknown>:0 at System.Linq.Enumerable.ToArray[PlaceItem] (IEnumerable`1 source) [0x00000] in <filename unknown>:0 at Firefox.PlacesItemSource.UpdateItems () [0x00000] in <filename unknown>:0 at Do.Universe.Safe.SafeItemSource.UpdateItems () [0x00000] in <filename unknown>:0 . Do.Universe.Linux.GNOMESpecialLocationsItemSource "GNOME Special Locations" encountered an error in UpdateItems: System.IO.FileNotFoundException: Could not find file "/root/.gtk-bookmarks". File name: '/root/.gtk-bookmarks' at System.IO.FileStream..ctor (System.String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, Boolean anonymous, FileOptions options) [0x00000] in <filename unknown>:0 at System.IO.FileStream..ctor (System.String path, FileMode mode, FileAccess access, FileShare share) [0x00000] in <filename unknown>:0 at (wrapper remoting-invoke-with-check) System.IO.FileStream:.ctor (string,System.IO.FileMode,System.IO.FileAccess,System.IO.FileShare) at System.IO.File.OpenRead (System.String path) [0x00000] in <filename unknown>:0 at System.IO.StreamReader..ctor (System.String path, System.Text.Encoding encoding, Boolean detectEncodingFromByteOrderMarks, Int32 bufferSize) [0x00000] in <filename unknown>:0 at System.IO.StreamReader..ctor (System.String path) [0x00000] in <filename unknown>:0 at (wrapper remoting-invoke-with-check) System.IO.StreamReader:.ctor (string) at Do.Universe.Linux.GNOMESpecialLocationsItemSource+<ReadBookmarkItems>c__Iterator3.MoveNext () [0x00000] in <filename unknown>:0 at Do.Universe.Linux.GNOMESpecialLocationsItemSource.UpdateItems () [0x00000] in <filename unknown>:0 at Do.Universe.Safe.SafeItemSource.UpdateItems () [0x00000] in <filename unknown>:0 . ^[^\Full thread dump: "<unnamed thread>" tid=0x0xb7570700 this=0x0x56f18 thread handle 0x403 state : not waiting owns () at (wrapper managed-to-native) Mono.Unix.Native.Syscall.read (int,intptr,ulong) <0xffffffff> at Mono.Unix.Native.Syscall.read (int,void*,ulong) <0x00023> at Mono.Unix.UnixStream.Read (byte[],int,int) <0x0008b> at NDesk.DBus.Connection.ReadMessage () <0x0003c> at NDesk.DBus.Connection.Iterate () <0x0001b> at NDesk.DBus.BusG/<Init>c__AnonStorey0.<>m__0 (intptr,NDesk.GLib.IOCondition,intptr) <0x00033> at (wrapper native-to-managed) NDesk.DBus.BusG/<Init>c__AnonStorey0.<>m__0 (intptr,NDesk.GLib.IOCondition,intptr) <0xffffffff> at (wrapper managed-to-native) Gtk.Clipboard.gtk_clipboard_wait_is_text_available (intptr) <0xffffffff> at Gtk.Clipboard.WaitIsTextAvailable () <0x00017> at Do.Universe.SelectedTextItem.UpdateSelection (object,System.EventArgs) <0x00027> at Do.Platform.AbstractApplicationService.OnSummoned () <0x00025> at Do.Platform.ApplicationService.<ApplicationService>m__31 (object,System.EventArgs) <0x00013> at Do.Core.Controller.OnSummoned () <0x00025> at Do.Core.Controller.Summon () <0x00027> at Do.Do.Main (string[]) <0x001eb> at (wrapper runtime-invoke) <Module>.runtime_invoke_void_object (object,intptr,intptr,intptr) <0xffffffff> "<unnamed thread>" tid=0x0xb2c81b40 this=0x0x194150 thread handle 0x412 state : interrupted state owns () at (wrapper managed-to-native) System.IO.InotifyWatcher.ReadFromFD (intptr,byte[],intptr) <0xffffffff> at System.IO.InotifyWatcher.Monitor () <0x0005f> at System.Threading.Thread.StartInternal () <0x00057> at (wrapper runtime-invoke) object.runtime_invoke_void__this__ (object,intptr,intptr,intptr) <0xffffffff> "Universe Update Dispatcher" tid=0x0xb29ffb40 this=0x0x569d8 thread handle 0x41b state : interrupted state owns () at (wrapper managed-to-native) System.Threading.WaitHandle.WaitOne_internal (System.Threading.WaitHandle,intptr,int,bool) <0xffffffff> at System.Threading.WaitHandle.WaitOne (System.TimeSpan,bool) <0x00133> at System.Threading.WaitHandle.WaitOne (System.TimeSpan) <0x00022> at Do.Core.UniverseManager.UniverseUpdateLoop () <0x0007a> at System.Threading.Thread.StartInternal () <0x00057> at (wrapper runtime-invoke) object.runtime_invoke_void__this__ (object,intptr,intptr,intptr) <0xffffffff> Tomboy.NotesItemSource "Tomboy Notes" encountered an error in UpdateItems: System.TypeInitializationException: An exception was thrown by the type initializer for Tomboy.TomboyDBus ---> System.Exception: Unable to open the session message bus. ---> System.ArgumentNullException: Argument cannot be null. Parameter name: address at NDesk.DBus.Bus.Open (System.String address) [0x00000] in <filename unknown>:0 at NDesk.DBus.Bus.get_Session () [0x00000] in <filename unknown>:0 --- End of inner exception stack trace --- at NDesk.DBus.Bus.get_Session () [0x00000] in <filename unknown>:0 at Tomboy.TomboyDBus..cctor () [0x00000] in <filename unknown>:0 --- End of inner exception stack trace --- at Tomboy.NotesItemSource.UpdateItems () [0x00000] in <filename unknown>:0 at Do.Universe.Safe.SafeItemSource.UpdateItems () [0x00000] in <filename unknown>:0 . Firefox.PlacesItemSource "Firefox Places" encountered an error in UpdateItems: System.InvalidCastException: Cannot cast from source type to destination type. at Mono.Data.Sqlite.SqliteDataReader.VerifyType (Int32 i, DbType typ) [0x00000] in <filename unknown>:0 at Mono.Data.Sqlite.SqliteDataReader.GetString (Int32 i) [0x00000] in <filename unknown>:0 at Firefox.PlacesItemSource+<LoadPlaceItems>c__Iterator3.MoveNext () [0x00000] in <filename unknown>:0 at System.Collections.Generic.List`1[Firefox.PlaceItem].AddEnumerable (IEnumerable`1 enumerable) [0x00000] in <filename unknown>:0 at System.Collections.Generic.List`1[Firefox.PlaceItem]..ctor (IEnumerable`1 collection) [0x00000] in <filename unknown>:0 at System.Linq.Enumerable.ToArray[PlaceItem] (IEnumerable`1 source) [0x00000] in <filename unknown>:0 at Firefox.PlacesItemSource.UpdateItems () [0x00000] in <filename unknown>:0 at Do.Universe.Safe.SafeItemSource.UpdateItems () [0x00000] in <filename unknown>:0 . Do.Universe.Linux.GNOMESpecialLocationsItemSource "GNOME Special Locations" encountered an error in UpdateItems: System.IO.FileNotFoundException: Could not find file "/root/.gtk-bookmarks". File name: '/root/.gtk-bookmarks' at System.IO.FileStream..ctor (System.String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, Boolean anonymous, FileOptions options) [0x00000] in <filename unknown>:0 at System.IO.FileStream..ctor (System.String path, FileMode mode, FileAccess access, FileShare share) [0x00000] in <filename unknown>:0 at (wrapper remoting-invoke-with-check) System.IO.FileStream:.ctor (string,System.IO.FileMode,System.IO.FileAccess,System.IO.FileShare) at System.IO.File.OpenRead (System.String path) [0x00000] in <filename unknown>:0 at System.IO.StreamReader..ctor (System.String path, System.Text.Encoding encoding, Boolean detectEncodingFromByteOrderMarks, Int32 bufferSize) [0x00000] in <filename unknown>:0 at System.IO.StreamReader..ctor (System.String path) [0x00000] in <filename unknown>:0 at (wrapper remoting-invoke-with-check) System.IO.StreamReader:.ctor (string) at Do.Universe.Linux.GNOMESpecialLocationsItemSource+<ReadBookmarkItems>c__Iterator3.MoveNext () [0x00000] in <filename unknown>:0 at Do.Universe.Linux.GNOMESpecialLocationsItemSource.UpdateItems () [0x00000] in <filename unknown>:0 at Do.Universe.Safe.SafeItemSource.UpdateItems () [0x00000] in <filename unknown>:0 . It stops when I try my key combination, ctrl-alt-. It does not pop up though.

  Read the article

• C# Extension Methods - To Extend or Not To Extend...

  - by James Michael Hare

  I've been thinking a lot about extension methods lately, and I must admit I both love them and hate them. They are a lot like sugar, they taste so nice and sweet, but they'll rot your teeth if you eat them too much.   I can't deny that they aren't useful and very handy. One of the major components of the Shared Component library where I work is a set of useful extension methods. But, I also can't deny that they tend to be overused and abused to willy-nilly extend every living type.   So what constitutes a good extension method? Obviously, you can write an extension method for nearly anything whether it is a good idea or not. Many times, in fact, an idea seems like a good extension method but in retrospect really doesn't fit.   So what's the litmus test? To me, an extension method should be like in the movies when a person runs into their twin, separated at birth. You just know you're related. Obviously, that's hard to quantify, so let's try to put a few rules-of-thumb around them.   A good extension method should:     Apply to any possible instance of the type it extends.     Simplify logic and improve readability/maintainability.     Apply to the most specific type or interface applicable.     Be isolated in a namespace so that it does not pollute IntelliSense.     So let's look at a few examples in relation to these rules.   The first rule, to me, is the most important of all. Once again, it bears repeating, a good extension method should apply to all possible instances of the type it extends. It should feel like the long lost relative that should have been included in the original class but somehow was missing from the family tree.    Take this nifty little int extension, I saw this once in a blog and at first I really thought it was pretty cool, but then I started noticing a code smell I couldn't quite put my finger on. So let's look:       public static class IntExtensinos     {         public static int Seconds(int num)         {             return num * 1000;         }           public static int Minutes(int num)         {             return num * 60000;         }     }     This is so you could do things like:       ...     Thread.Sleep(5.Seconds());     ...     proxy.Timeout = 1.Minutes();     ...     Awww, you say, that's cute! Well, that's the problem, it's kitschy and it doesn't always apply (and incidentally you could achieve the same thing with TimeStamp.FromSeconds(5)). It's syntactical candy that looks cool, but tends to rot and pollute the code. It would allow things like:       total += numberOfTodaysOrders.Seconds();     which makes no sense and should never be allowed. The problem is you're applying an extension method to a logical domain, not a type domain. That is, the extension method Seconds() doesn't really apply to ALL ints, it applies to ints that are representative of time that you want to convert to milliseconds.    Do you see what I mean? The two problems, in a nutshell, are that a) Seconds() called off a non-time value makes no sense and b) calling Seconds() off something to pass to something that does not take milliseconds will be off by a factor of 1000 or worse.   Thus, in my mind, you should only ever have an extension method that applies to the whole domain of that type.   For example, this is one of my personal favorites:       public static bool IsBetween<T>(this T value, T low, T high)         where T : IComparable<T>     {         return value.CompareTo(low) >= 0 && value.CompareTo(high) <= 0;     }   This allows you to check if any IComparable<T> is within an upper and lower bound. Think of how many times you type something like:       if (response.Employee.Address.YearsAt >= 2         && response.Employee.Address.YearsAt <= 10)     {     ...     }     Now, you can instead type:       if(response.Employee.Address.YearsAt.IsBetween(2, 10))     {     ...     }     Note that this applies to all IComparable<T> -- that's ints, chars, strings, DateTime, etc -- and does not depend on any logical domain. In addition, it satisfies the second point and actually makes the code more readable and maintainable.   Let's look at the third point. In it we said that an extension method should fit the most specific interface or type possible. Now, I'm not saying if you have something that applies to enumerables, you create an extension for List, Array, Dictionary, etc (though you may have reasons for doing so), but that you should beware of making things TOO general.   For example, let's say we had an extension method like this:       public static T ConvertTo<T>(this object value)     {         return (T)Convert.ChangeType(value, typeof(T));     }         This lets you do more fluent conversions like:       double d = "5.0".ConvertTo<double>();     However, if you dig into Reflector (LOVE that tool) you will see that if the type you are calling on does not implement IConvertible, what you convert to MUST be the exact type or it will throw an InvalidCastException. Now this may or may not be what you want in this situation, and I leave that up to you. Things like this would fail:       object value = new Employee();     ...     // class cast exception because typeof(IEmployee) != typeof(Employee)     IEmployee emp = value.ConvertTo<IEmployee>();       Yes, that's a downfall of working with Convertible in general, but if you wanted your fluent interface to be more type-safe so that ConvertTo were only callable on IConvertibles (and let casting be a manual task), you could easily make it:         public static T ConvertTo<T>(this IConvertible value)     {         return (T)Convert.ChangeType(value, typeof(T));     }         This is what I mean by choosing the best type to extend. Consider that if we used the previous (object) version, every time we typed a dot ('.') on an instance we'd pull up ConvertTo() whether it was applicable or not. By filtering our extension method down to only valid types (those that implement IConvertible) we greatly reduce our IntelliSense pollution and apply a good level of compile-time correctness.   Now my fourth rule is just my general rule-of-thumb. Obviously, you can make extension methods as in-your-face as you want. I included all mine in my work libraries in its own sub-namespace, something akin to:       namespace Shared.Core.Extensions { ... }     This is in a library called Shared.Core, so just referencing the Core library doesn't pollute your IntelliSense, you have to actually do a using on Shared.Core.Extensions to bring the methods in. This is very similar to the way Microsoft puts its extension methods in System.Linq. This way, if you want 'em, you use the appropriate namespace. If you don't want 'em, they won't pollute your namespace.   To really make this work, however, that namespace should only include extension methods and subordinate types those extensions themselves may use. If you plant other useful classes in those namespaces, once a user includes it, they get all the extensions too.   Also, just as a personal preference, extension methods that aren't simply syntactical shortcuts, I like to put in a static utility class and then have extension methods for syntactical candy. For instance, I think it imaginable that any object could be converted to XML:       namespace Shared.Core     {         // A collection of XML Utility classes         public static class XmlUtility         {             ...             // Serialize an object into an xml string             public static string ToXml(object input)             {                 var xs = new XmlSerializer(input.GetType());                   // use new UTF8Encoding here, not Encoding.UTF8. The later includes                 // the BOM which screws up subsequent reads, the former does not.                 using (var memoryStream = new MemoryStream())                 using (var xmlTextWriter = new XmlTextWriter(memoryStream, new UTF8Encoding()))                 {                     xs.Serialize(xmlTextWriter, input);                     return Encoding.UTF8.GetString(memoryStream.ToArray());                 }             }             ...         }     }   I also wanted to be able to call this from an object like:       value.ToXml();     But here's the problem, if i made this an extension method from the start with that one little keyword "this", it would pop into IntelliSense for all objects which could be very polluting. Instead, I put the logic into a utility class so that users have the choice of whether or not they want to use it as just a class and not pollute IntelliSense, then in my extensions namespace, I add the syntactical candy:       namespace Shared.Core.Extensions     {         public static class XmlExtensions         {             public static string ToXml(this object value)             {                 return XmlUtility.ToXml(value);             }         }     }   So now it's the best of both worlds. On one hand, they can use the utility class if they don't want to pollute IntelliSense, and on the other hand they can include the Extensions namespace and use as an extension if they want. The neat thing is it also adheres to the Single Responsibility Principle. The XmlUtility is responsible for converting objects to XML, and the XmlExtensions is responsible for extending object's interface for ToXml().

  Read the article

< Previous Page | 315 316 317 318 319 320 321 322 323 324 325 326  | Next Page >