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  • Delphi Exception handling problem with multiple Exception handling blocks

    - by Robert Oschler
    I'm using Delphi Pro 6 on Windows XP with FastMM 4.92 and the JEDI JVCL 3.0. Given the code below, I'm having the following problem: only the first exception handling block gets a valid instance of E. The other blocks match properly with the class of the Exception being raised, but E is unassigned (nil). For example, given the current order of the exception handling blocks when I raise an E1 the block for E1 matches and E is a valid object instance. However, if I try to raise an E2, that block does match, but E is unassigned (nil). If I move the E2 catching block to the top of the ordering and raise an E1, then when the E1 block matches E is is now unassigned. With this new ordering if I raise an E2, E is properly assigned when it wasn't when the E2 block was not the first block in the ordering. Note I tried this case with a bare-bones project consisting of just a single Delphi form. Am I doing something really silly here or is something really wrong? Thanks, Robert type E1 = class(EAbort) end; E2 = class(EAbort) end; procedure TForm1.Button1Click(Sender: TObject); begin try raise E1.Create('hello'); except On E: E1 do begin OutputDebugString('E1'); end; On E: E2 do begin OutputDebugString('E2'); end; On E: Exception do begin OutputDebugString('E(all)'); end; end; // try() end;

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  • Delph Exception handling problem with multiple Exception handling blocks

    - by Robert Oschler
    I'm using Delphi Pro 6 on Windows XP with FastMM 4.92 and the JEDI JVCL 3.0. Given the code below, I'm having the following problem: only the first exception handling block gets a valid instance of E. The other blocks match properly with the class of the Exception being raised, but E is unassigned (nil). For example, given the current order of the exception handling blocks when I raise an E1 the block for E1 matches and E is a valid object instance. However, if I try to raise an E2, that block does match, but E is unassigned (nil). If I move the E2 catching block to the top of the ordering and raise an E1, then when the E1 block matches E is is now unassigned. With this new ordering if I raise an E2, E is properly assigned when it wasn't when the E2 block was not the first block in the ordering. Note I tried this case with a bare-bones project consisting of just a single Delphi form. Am I doing something really silly here or is something really wrong? Thanks, Robert type E1 = class(EAbort) end; E2 = class(EAbort) end; procedure TForm1.Button1Click(Sender: TObject); begin try raise E1.Create('hello'); except On E: E1 do begin OutputDebugString('E1'); end; On E: E2 do begin OutputDebugString('E2'); end; On E: Exception do begin OutputDebugString('E(all)'); end; end; // try() end;

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  • MySQL Database Query Problem

    - by moustafa
    I need your help!!!. I need to query a table in my database that has record of goods sold. I want the query to detect a particular product and also calculate the quantity sold. The product are 300 now, but it would increase in the future. Below is a sample of my DB Table #---------------------------- # Table structure for litorder #---------------------------- CREATE TABLE `litorder` ( `id` int(10) NOT NULL auto_increment, `name` varchar(50) NOT NULL default '', `address` varchar(50) NOT NULL default '', `xdate` date NOT NULL default '0000-00-00', `ref` varchar(20) NOT NULL default '', `code1` varchar(50) NOT NULL default '', `code2` varchar(50) NOT NULL default '', `code3` varchar(50) NOT NULL default '', `code4` varchar(50) NOT NULL default '', `code5` varchar(50) NOT NULL default '', `code6` varchar(50) NOT NULL default '', `code7` varchar(50) NOT NULL default '', `code8` varchar(50) NOT NULL default '', `code9` varchar(50) NOT NULL default '', `code10` varchar(50) NOT NULL default '', `code11` varchar(50) character set latin1 collate latin1_bin NOT NULL default '', `code12` varchar(50) NOT NULL default '', `code13` varchar(50) NOT NULL default '', `code14` varchar(50) NOT NULL default '', `code15` varchar(50) NOT NULL default '', `product1` varchar(100) NOT NULL default '0', `product2` varchar(100) NOT NULL default '0', `product3` varchar(100) NOT NULL default '0', `product4` varchar(100) NOT NULL default '0', `product5` varchar(100) NOT NULL default '0', `product6` varchar(100) NOT NULL default '0', `product7` varchar(100) NOT NULL default '0', `product8` varchar(100) NOT NULL default '0', `product9` varchar(100) NOT NULL default '0', `product10` varchar(100) NOT NULL default '0', `product11` varchar(100) NOT NULL default '0', `product12` varchar(100) NOT NULL default '0', `product13` varchar(100) NOT NULL default '0', `product14` varchar(100) NOT NULL default '0', `product15` varchar(100) NOT NULL default '0', `price1` int(10) NOT NULL default '0', `price2` int(10) NOT NULL default '0', `price3` int(10) NOT NULL default '0', `price4` int(10) NOT NULL default '0', `price5` int(10) NOT NULL default '0', `price6` int(10) NOT NULL default '0', `price7` int(10) NOT NULL default '0', `price8` int(10) NOT NULL default '0', `price9` int(10) NOT NULL default '0', `price10` int(10) NOT NULL default '0', `price11` int(10) NOT NULL default '0', `price12` int(10) NOT NULL default '0', `price13` int(10) NOT NULL default '0', `price14` int(10) NOT NULL default '0', `price15` int(10) NOT NULL default '0', `quantity1` int(10) NOT NULL default '0', `quantity2` int(10) NOT NULL default '0', `quantity3` int(10) NOT NULL default '0', `quantity4` int(10) NOT NULL default '0', `quantity5` int(10) NOT NULL default '0', `quantity6` int(10) NOT NULL default '0', `quantity7` int(10) NOT NULL default '0', `quantity8` int(10) NOT NULL default '0', `quantity9` int(10) NOT NULL default '0', `quantity10` int(10) NOT NULL default '0', `quantity11` int(10) NOT NULL default '0', `quantity12` int(10) NOT NULL default '0', `quantity13` int(10) NOT NULL default '0', `quantity14` int(10) NOT NULL default '0', `quantity15` int(10) NOT NULL default '0', `amount1` int(10) NOT NULL default '0', `amount2` int(10) NOT NULL default '0', `amount3` int(10) NOT NULL default '0', `amount4` int(10) NOT NULL default '0', `amount5` int(10) NOT NULL default '0', `amount6` int(10) NOT NULL default '0', `amount7` int(10) NOT NULL default '0', `amount8` int(10) NOT NULL default '0', `amount9` int(10) NOT NULL default '0', `amount10` int(10) NOT NULL default '0', `amount11` int(10) NOT NULL default '0', `amount12` int(10) NOT NULL default '0', `amount13` int(10) NOT NULL default '0', `amount14` int(10) NOT NULL default '0', `amount15` int(10) NOT NULL default '0', `totalNaira` double(20,0) NOT NULL default '0', `totalDollar` int(20) NOT NULL default '0', PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 COMMENT='InnoDB free: 4096 kB; InnoDB free: 4096 kB; InnoDB free: 409'; #---------------------------- # Records for table litorder #---------------------------- insert into litorder values (27, 'Sanyaolu Fisayo', '14 Adegboyega Street Palmgrove Lagos', '2010-05-31', '', 'DL 001', 'DL 002', 'DL 003', '', '', '', '', '', '', '', '', '', '', '', '', 'AILMENT & PREVENTION DVD- ENGLISH', 'AILMENT & PREVENTION DVD- HAUSA', 'BEAUTY CD', '', '', '', '', '', '', '', '', '', '', '', '', 800, 800, 3000, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 16, 20, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12800, 12800, 60000, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, '85600', 563), (28, 'Irenonse Esther', 'Lagos,Nigeria', '2010-06-01', '', 'DL 005', 'DL 008', 'FC 004', '', '', '', '', '', '', '', '', '', '', '', '', 'GET HEALTHY DVD', 'YOUR FUTURE DVD', 'FOREVER FACE CAP (YELLOW)', '', '', '', '', '', '', '', '', '', '', '', '', 1000, 900, 2000, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2000, 1800, 6000, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, '9800', 64), (29, 'Kalu Lekway', 'Lagos, Nigeria', '2010-06-01', '', 'DL 001', 'DL 003', '', '', '', '', '', '', '', '', '', '', '', '', '', 'AILMENT & PREVENTION DVD- ENGLISH', 'BEAUTY CD', '', '', '', '', '', '', '', '', '', '', '', '', '', 800, 3000, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2400, 18000, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, '20400', 133), (30, 'Dele', 'Ilupeju', '2010-06-02', '', 'DL 001', 'DL 003', '', '', '', '', '', '', '', '', '', '', '', '', '', 'AILMENT & PREVENTION DVD- ENGLISH', 'BEAUTY CD', '', '', '', '', '', '', '', '', '', '', '', '', '', 800, 3000, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 10, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8000, 30000, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, '38000', 250);

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  • Resuming execution of code after exception is thrown and caught

    - by dotnetdev
    Hi, How is it possible to resume code execution after an exception is thrown? For exampel, take the following code: namespace ConsoleApplication1 { class Test { public void s() { throw new NotSupportedException(); string @class = "" ; Console.WriteLine(@class); Console.ReadLine(); } } class Program { static void Main(string[] args) { try { new Test().s(); } catch (ArgumentException x) { } catch (Exception ex) { } } } } After catching the exception when stepping through, the program will stop running. How can I still carry on execution? Thanks

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  • Where did my Visual Studio exception assistant go?

    - by Steven
    Since a couple of weeks the Visual Studio (2008 9.0.30729.1 SP) Exception Assistant has stopt appearing while debugging using the C# IDE. Instead the old ugly and useless debug dialog comes up: To make sure, I've checked the following: "Tools / Options / Debugging / General / Enable the exception assistant" is on. "Debug / Exceptions / Common Language Runtime Exceptions / Thrown" is on. I reset my Visual Studio Settings. I googled. I checked all relevant stackoverflow questions. How can I get the Exception Assistant back? Who gives me the golden tip?

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  • How to debug "The type initializer for 'my class' threw an exception"

    - by JFB
    I am getting the exception: The type initializer for 'my class' threw an exception. in my browser after running my web application. Since this seems to be an error message generated from the view (.aspx), there is no way I can see the stack trace or any log for the source of this error. I have read a bit around the net and one solution to debugging is to throw a TypeInitializationException and then looking at the inner exception to find out what was wrong. How can I do this when I don't know where to surround code with a try/catch ?

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  • Fatal error: Uncaught exception 'Exception' in PHPExcel classes

    - by Chakrapani
    Can any one please let me know, why this following error has been thrown from PHPExcel classes Fatal error: Uncaught exception 'Exception' with message 'Could not close zip file /var/www/mydomain/myexcel.xlsx.' in /var/www/mydomain/Classes/PHPExcel/Writer /Excel2007.php:400 Stack trace: #0 /var/www/mydomain/myexcel.php(173): PHPExcel_Writer_Excel2007->save('/var/www/mydomain...') #1 {main} thrown in /var/www/mydomain/Classes/PHPExcel/Writer/Excel2007.php on line 400

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  • Automatic bookkeeping for exception retries

    - by pilcrow
    Do any languages that support retry constructs in exception handling track and expose the number of times their catch/rescue (and/or try/begin) blocks have been executed in a particular run? I find myself counting (and limiting) the number of times a code block is re-executed after an exception often enough that this would be a handy language built-in.

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  • DUMP in unhandled C++ exception

    - by Jorge Vasquez
    In MSVC, how can I make any unhandled C++ exception (std::runtime_error, for instance) crash my release-compiled program so that it generates a dump with the full stack from the exception throw location? I have installed NTSD in the AeDebug registry an can generate good dumps for things like memory access violation, so the matter here comes down to crashing the program correctly, I suppose. Thanks in advance.

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  • null coalescing operator for javascript?

    - by Daniel Schaffer
    I assumed this question has already been asked here, but I couldn't find any, so here it goes: Is there a null coalescing operator in Javascript? For example, in C#, I can do this: String someString = null; var whatIWant = someString ?? "Cookies!"; The best approximation I can figure out for Javascript is using the conditional operator: var someString = null; var whatIWant = someString ? someString : 'Cookies!'; Which is sorta icky IMHO. Can I do better?

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  • Model View Control Issue: Null Pointer Initialization Question [closed]

    - by David Dimalanta
    Good morning again. This is David. Please, I need an urgent help regarding control model view where I making a code that uniquely separating into groups: An Activity Java Class to Display the Interface A View and Function Java Class for Drawing Cards and Display it on the Activity Class The problem is that the result returns a Null Pointer Exception. I have initialize for the ID for Text View and Image View. Under this class "draw_deck.java". Please help me. Here's my code for draw_deck.java: package com.bodapps.inbetween.model; import android.content.Context; import android.view.View; import android.widget.ImageView; import android.widget.TextView; import com.bodapps.inbetween.R; public class draw_deck extends View { public TextView count_label; public ImageView draw_card; private int count; public draw_deck(Context context) { super(context); // TODO Auto-generated constructor stub //I have initialized two widgets for ID. I still don't get it why I got forced closed by Null Pointer Exception thing. draw_card = (ImageView) findViewById(R.id.IV_Draw_Card); count_label = (TextView) findViewById(R.id.Text_View_Count_Card); } public void draw(int s, int c, String strSuit, String strValue, Pile pile, Context context) { //super(context); //Just printing the card drawn from pile int suit, value = 1; draw_card = (ImageView) findViewById(R.id.IV_Draw_Card); count_label = (TextView) findViewById(R.id.Text_View_Count_Card); Card card; if(!pile.isEmpty()) //Setting it to IF statement displays the card one by one. { card = pile.drawFromPile(); //Need to check first if card is null. if (card != null) { //draws an extra if (card != null) { //Get suit of card to print out. suit = card.getSuit(); switch (suit) { case CardInfo.DIAMOND: strSuit = "DIAMOND"; s=0; break; case CardInfo.HEART: strSuit = "HEART"; s=1; break; case CardInfo.SPADE: strSuit = "SPADE"; s=2; break; case CardInfo.CLUB: strSuit = "CLUB"; s=3; break; } //Get value of card to print out. value = card.getValue(); switch (value) { case CardInfo.ACE: strValue = "ACE"; c=0; break; case CardInfo.TWO: c=1; break; case CardInfo.THREE: strValue = "THREE"; c=2; break; case CardInfo.FOUR: strValue = "FOUR"; c=3; break; case CardInfo.FIVE: strValue = "FIVE"; c=4; break; case CardInfo.SIX: strValue = "SIX"; c=4; break; case CardInfo.SEVEN: strValue = "SEVEN"; c=4; break; case CardInfo.EIGHT: strValue = "EIGHT"; c=4; break; case CardInfo.NINE: strValue = "NINE"; c=4; break; case CardInfo.TEN: strValue = "TEN"; c=4; break; case CardInfo.JACK: strValue = "JACK"; c=4; break; case CardInfo.QUEEN: strValue = "QUEEN"; c=4; break; case CardInfo.KING: strValue = "KING"; c=4; break; } } } }// //Below two lines of code, this is where issued the Null Pointer Exception. draw_card.setImageResource(deck[s][c]); count_label.setText(new StringBuilder(strValue).append(" of ").append(strSuit).append(String.valueOf(" " + count++)).toString()); } //Choice of Suits in a Deck public Integer[][] deck = { //Array Group 1 is [0][0] (No. of Cards: 4 - DIAMOND) { R.drawable.card_dummy_1, R.drawable.card_dummy_2, R.drawable.card_dummy_4, R.drawable.card_dummy_5, R.drawable.card_dummy_3 }, //Array Group 2 is [1][0] (No. of Cards: 4 - HEART) { R.drawable.card_dummy_1, R.drawable.card_dummy_2, R.drawable.card_dummy_4, R.drawable.card_dummy_5, R.drawable.card_dummy_3 }, //Array Group 3 is [2][0] (No. of Cards: 4 - SPADE) { R.drawable.card_dummy_1, R.drawable.card_dummy_2, R.drawable.card_dummy_4, R.drawable.card_dummy_5, R.drawable.card_dummy_3 }, //Array Group 4 is [3][0] (No. of Cards: 4 - CLUB) { R.drawable.card_dummy_1, R.drawable.card_dummy_2, R.drawable.card_dummy_4, R.drawable.card_dummy_5, R.drawable.card_dummy_3 }, }; } And this one of the activity class, Player_Mode_2.java: package com.bodapps.inbetween; import java.util.Random; import android.app.Activity; import android.app.Dialog; import android.content.Context; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.EditText; import android.widget.ImageView; import android.widget.TextView; import android.widget.Toast; import com.bodapps.inbetween.model.Card; import com.bodapps.inbetween.model.Pile; import com.bodapps.inbetween.model.draw_deck; /* * * Public class for Two-Player mode. * */ public class Player_Mode_2 extends Activity { //Image Views private ImageView draw_card; private ImageView player_1; private ImageView player_2; private ImageView icon; //Buttons private Button set_deck; //Edit Texts private EditText enter_no_of_decks; //text Views private TextView count_label; //Integer Data Types private int no_of_cards, count; private int card_multiplier; //Contexts final Context context = this; //Pile Model public Pile pile; //Card Model public Card card; //create View @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.play_2_player_mode); //-----[ Search for Views ]----- //Initialize for Image View draw_card = (ImageView) findViewById(R.id.IV_Draw_Card); player_1 = (ImageView) findViewById(R.id.IV_Player_1_Card); player_2 = (ImageView) findViewById(R.id.IV_Player_2_Card); //Initialize for Text view or Label count_label = (TextView) findViewById(R.id.Text_View_Count_Card); //-----[ Adding Values ]----- //Integer Values count = 0; no_of_cards = 0; //-----[ Adding Dialog ]----- //Initializing Dialog final Dialog deck_dialog = new Dialog(context); deck_dialog.setContentView(R.layout.dialog); deck_dialog.setTitle("Deck Dialog"); //-----[ Initializing Views for Dialog's Contents ]----- //Initialize for Edit Text enter_no_of_decks = (EditText) deck_dialog.findViewById(R.id.Edit_Text_Set_Number_of_Decks); //Initialize for Button set_deck = (Button) deck_dialog.findViewById(R.id.Button_Deck); //-----[ Setting onClickListener() ]----- //Set Event Listener for Image view draw_card.setOnClickListener(new Draw_Card_Model()); //Set Event Listener for Setting the Deck set_deck.setOnClickListener(new OnClickListener() { public void onClick(View v) { if(card_multiplier <= 8) { //Use "Integer.parseInt()" method to instantly convert from String to int value. card_multiplier = Integer.parseInt(enter_no_of_decks.getText().toString()); //Shuffling cards... pile = new Pile(card_multiplier); //Multiply no. of decks //Dismiss or close the dialog. deck_dialog.dismiss(); } else { Toast.makeText(getApplicationContext(), "Please choose a number from 1 to 8.", Toast.LENGTH_SHORT).show(); } } }); //Show dialog. deck_dialog.show(); } //Shuffling the Array public void Shuffle_Cards(Integer[][] Shuffle_Deck) { Random random = new Random(); for(int i = Shuffle_Deck[no_of_cards].length - 1; i >=0; i--) { int Index = random.nextInt(i + 1); //Simple Swapping Integer swap = Shuffle_Deck[card_multiplier-1][Index]; Shuffle_Deck[card_multiplier-1][Index] = Shuffle_Deck[card_multiplier-1][i]; Shuffle_Deck[card_multiplier-1][i] = swap; } } //Private Class for Random Card Draw private class Draw_Card_Model implements OnClickListener { public void onClick(View v) { //Just printing the card drawn from pile int suit = 0, value = 0; String strSuit = "", strValue = ""; draw_deck draw = new draw_deck(context); //This line is where issued the Null Pointer Exception. if (count == card_multiplier*52) { // A message shows up when all cards are draw out. Toast.makeText(getApplicationContext(), "All cards have been used up.", Toast.LENGTH_SHORT).show(); draw_card.setEnabled(false); } else { draw.draw(suit, value, strSuit, strValue, pile, context); count_label.setText(count); //This is where I got force closed error, although "int count" have initialized the number. This was supposed to accept in the setText() method. count++; } } } } Take note that the issues on Null Pointer Exception is the Image View and the Edit Text. I got to test it. Thanks. If you have any info about my question, let me know it frankly.

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  • Java Swing GUI exception - Exception in thread "AWT-EventQueue-0" java.util.NoSuchElementException:

    - by rgksugan
    I get this exception when i run my application. I dont have any idea what is going wrong here. Can someone help please. Exception in thread "AWT-EventQueue-0" java.util.NoSuchElementException: Vector Enumeration at java.util.Vector$1.nextElement(Vector.java:305) at javax.swing.plaf.basic.BasicTableHeaderUI.getPreferredSize(BasicTableHeaderUI.java:778) at javax.swing.JComponent.getPreferredSize(JComponent.java:1634) at javax.swing.ViewportLayout.preferredLayoutSize(ViewportLayout.java:78) at java.awt.Container.preferredSize(Container.java:1599) at java.awt.Container.getPreferredSize(Container.java:1584) at javax.swing.JComponent.getPreferredSize(JComponent.java:1636) at javax.swing.ScrollPaneLayout.layoutContainer(ScrollPaneLayout.java:702) at java.awt.Container.layout(Container.java:1421) at java.awt.Container.doLayout(Container.java:1410) at java.awt.Container.validateTree(Container.java:1507) at java.awt.Container.validate(Container.java:1480) at javax.swing.RepaintManager.validateInvalidComponents(RepaintManager.java:669) at javax.swing.SystemEventQueueUtilities$ComponentWorkRequest.run(SystemEventQueueUtilities.java:124) at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209) at java.awt.EventQueue.dispatchEvent(EventQueue.java:597) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161) at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)

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  • I am getting exception in main thread...even when i am handling the exception

    - by fari
    public KalaGame(KeyBoardPlayer player1,KeyBoardPlayer player2) { //super(0); int key=0; try { do{ System.out.println("Enter the number of stones to play with: "); BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); key = Integer.parseInt(br.readLine()); if(key<0 || key>10) throw new InvalidStartingStonesException(key); } while(key<0 || key>10); player1=new KeyBoardPlayer(); player2 = new KeyBoardPlayer(); this.player1=player1; this.player2=player2; state=new KalaGameState(key); } catch(IOException e) { System.out.println(e); } } when i enter an invalid number of stones i get this error Exception in thread "main" InvalidStartingStonesException: The number of starting stones must be greater than 0 and less than or equal to 10 (attempted 22) why isn't the exception handled by the throw i defined at KalaGame.<init>(KalaGame.java:27) at PlayKala.main(PlayKala.java:10)

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  • Better exception for non-exhaustive patterns in case

    - by toofarsideways
    Is there a way to get GHCi to produce better exception messages when it finds at runtime that a call has produced value that does not match the function's pattern matching? It currently gives the line numbers of the function which produced the non-exhaustive pattern match which though helpful at times does require a round of debugging which at times I feel is doing the same set of things over and over. So before I tried to put together a solution I wanted to see if something else exists. An exception message that in addition to giving the line numbers shows what kind of call it attempted to make? Is this even possible?

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  • What to log when an exception occurs?

    - by Rune
    public void EatDinner(string appetizer, string mainCourse, string dessert) { try { // Code } catch (Exception ex) { Logger.Log("Error in EatDinner", ex); return; } } When an exception occurs in a specific method, what should I be logging? I see a lot of the above in the code I work with. In these cases, I always have to talk to the person who experienced the error to find out what they were doing, step through the code, and try to reproduce the error. Is there any best practices or ways I can minimize all this extra work? Should I log the parameters in each method like this? Logger.Log("Params: " + appetizer + "," + mainCourse + "," + dessert, ex); Is there a better way to log the current environment? If I do it this way, will I need to write out all this stuff for each method I have in my application? Are there any best practices concerning scenarios like this?

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  • C++ Exception Handling

    - by user1413793
    So I was writing some code and I noticed that apart from syntactical, type, and other compile-time errors, C++ does not throw any other exceptions. So I decided to test this out with a very trivial program: #include<iostream> int main() { std::count<<5/0<<std::endl; return 1 } When I compiled it using g++, g++ gave me a warning saying I was dividing by 0. But it still compiled the code. Then when I ran it, it printed some really large arbitrary number. When I want to know is, how does C++ deal with exceptions? Integer division by 0 should be a very trivial example of when an exception should be thrown and the program should terminate. Do I have to essentially enclose my entire program in a huge try block and then catch certain exceptions? I know in Python when an exception is thrown, the program will immediately terminate and print out the error. What does C++ do? Are there even runtime exceptions which stop execution and kill the program?

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  • AS 3.0 reference problem

    - by vasion
    I am finding it hard to fugure out the reference system in AS 3.0. this is the code i have (i have trimmed it down in order to find the problem but to no avail) package rpflash.ui { import flash.display.Sprite; import flash.display.MovieClip; import flash.display.Stage; import nowplaying; import flash.text.TextField; public class RPUserInterface extends Sprite{ var np:nowplaying; public function RPUserInterface(){ } public function init(){ var np:nowplaying = new nowplaying(); this.addChild(np) } public function updateplayer(xml:XML){ var artist: String = xml.nowplaying.artist.toString(); var title: String = xml.nowplaying.title.toString(); trace("UI:update"); trace(this.np);// this gives me a null reference } } } and still i cannot access np!!! trace this.np gives me a null reference. i am not even trying to access it from a subling class. (btw i def want to know how to do that as well.)

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  • ASP.NET "Object reference not set..." error

    - by Roman
    Hi, I have a website written using ASP.NET. We have a development machine and a deployment server. The site works great on the development machine, but when is transfered (using simple FTP Upload) generates strange behavior. It starts working just fine, but after a while stops working and throws an exception "Exception: Object reference not set to an instance of an object.". The deal is that the absolute path of the website on the development machine is different than on the deployment server (and why should they be similar?) and the exact error is: Exception: Object reference not set to an instance of an object. at SOMEPROJECT_Objects.Player..ctor(Int32 PlayerID) in C:\inetpub\wwwroot\SOMEPROJECTSolution\ALLPROJECT\SOMEPROJECT_Objects\Player.cs:line 123 at SOMEPROJECT_GameLayer.M_Game.PlayerActiveGame(Int32 PlayerID) in C:\inetpub\wwwroot\SOMEPROJECTSolution\ALLPROJECT\SOMEPROJECT_GameLayer\M_Game.cs:line 85 at Web.getsms.Page_Load(Object sender, EventArgs e) in C:\inetpub\wwwroot\SOMEPROJECTSolution\ALLPROJECT\SOMEPROJECT-sms\Web\getsms.aspx.cs:line 59 The address that it is looking for is the address on the DEVELOPMENT machine, where as the site now resides on the deployment server. Any ideas why this happens would be appreciated. Thanks, Roman

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  • Cost of creating exception compared to cost of logging it

    - by Sebastien Lorber
    Hello, Just wonder how much cost to raise a java exception (or to call native fillInStackTrace() of Throwable) compared to what it cost to log it with log4j (in a file, with production hard drive)... Asking myself, when exceptions are raised, does it worth to often log them even if they are not necessary significant... (i work in a high load environment) Thanks

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  • Catching an exception class within a template

    - by Todd Bauer
    I'm having a problem using the exception class Overflow() for a Stack template I'm creating. If I define the class regularly there is no problem. If I define the class as a template, I cannot make my call to catch() work properly. I have a feeling it's simply syntax, but I can't figure it out for the life of me. #include<iostream> #include<exception> using namespace std; template <class T> class Stack { private: T *stackArray; int size; int top; public: Stack(int size) { this->size = size; stackArray = new T[size]; top = 0; } ~Stack() { delete[] stackArray; } void push(T value) { if (isFull()) throw Overflow(); stackArray[top] = value; top++; } bool isFull() { if (top == size) return true; else return false; } class Overflow {}; }; int main() { try { Stack<double> Stack(5); Stack.push( 5.0); Stack.push(10.1); Stack.push(15.2); Stack.push(20.3); Stack.push(25.4); Stack.push(30.5); } catch (Stack::Overflow) { cout << "ERROR! The stack is full.\n"; } return 0; } The problem is in the catch (Stack::Overflow) statement. As I said, if the class is not a template, this works just fine. However, once I define it as a template, this ceases to work. I've tried all sorts of syntaxes, but I always get one of two sets of error messages from the compiler. If I use catch(Stack::Overflow): ch18pr01.cpp(89) : error C2955: 'Stack' : use of class template requires template argument list ch18pr01.cpp(13) : see declaration of 'Stack' ch18pr01.cpp(89) : error C2955: 'Stack' : use of class template requires template argument list ch18pr01.cpp(13) : see declaration of 'Stack' ch18pr01.cpp(89) : error C2316: 'Stack::Overflow' : cannot be caught as the destructor and/or copy constructor are inaccessible EDIT: I meant If I use catch(Stack<double>::Overflow) or any variety thereof: ch18pr01.cpp(89) : error C2061: syntax error : identifier 'Stack' ch18pr01.cpp(89) : error C2310: catch handlers must specify one type ch18pr01.cpp(95) : error C2317: 'try' block starting on line '75' has no catch handlers I simply can not figure this out. Does anyone have any idea?

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  • Tracking the user function that threw the exception

    - by makerofthings7
    I've been given a large application with only one try..catch at the outer most level. This application also throws exceptions all the time, and is poorly documented. Is there any pattern I can implement that will tell me what user method is being called, the exception being thrown, and also the count of exceptions? I'm thinking of using a dictionary with reflection to get the needed information, but I'm not sure if this will work. What do you think?

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  • C++ display stack trace on exception

    - by rlbond
    I want to have a way to report the stack trace to the user if an exception is thrown. What is the best way to do this? Does it take huge amounts of extra code? To answer questions: I'd like it to be portable if possible. I want information to pop up, so the user can copy the stack trace and email it to me if an error comes up.

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  • LINQ query null reference exception

    - by user289082
    Hi! I have the next query: var bPermisos = from b in ruc.Permisos where b.IdUsuario == cu.Id select new Permisos(){ Id=b.Id, IdUsuario=b.Id, IdPerfil=b.Id, Estatus=b.Estatus }; var qSisPer = from perm in bPermisos select new { perm.IdPerfil,perm.Cat_Perfil.Nivel,perm.Cat_Perfil.Nombre,Nombre_Sistem=perm.Cat_Perfil.Cat_Sistema.Nombre}; And is throwing me an exception, plz help!

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