Search Results

Search found 4077 results on 164 pages for 'throw'.

Page 122/164 | < Previous Page | 118 119 120 121 122 123 124 125 126 127 128 129  | Next Page >

  • Accelerated C++, problem 5-6 (copying values from inside a vector to the front)

    - by Darel
    Hello, I'm working through the exercises in Accelerated C++ and I'm stuck on question 5-6. Here's the problem description: (somewhat abbreviated, I've removed extraneous info.) 5-6. Write the extract_fails function so that it copies the records for the passing students to the beginning of students, and then uses the resize function to remove the extra elements from the end of students. (students is a vector of student structures. student structures contain an individual student's name and grades.) More specifically, I'm having trouble getting the vector.insert function to properly copy the passing student structures to the start of the vector students. Here's the extract_fails function as I have it so far (note it doesn't resize the vector yet, as directed by the problem description; that should be trivial once I get past my current issue.) // Extract the students who failed from the "students" vector. void extract_fails(vector<Student_info>& students) { typedef vector<Student_info>::size_type str_sz; typedef vector<Student_info>::iterator iter; iter it = students.begin(); str_sz i = 0, count = 0; while (it != students.end()) { // fgrade tests wether or not the student failed if (!fgrade(*it)) { // if student passed, copy to front of vector students.insert(students.begin(), it, it); // tracks of the number of passing students(so we can properly resize the array) count++; } cout << it->name << endl; // output to verify that each student is iterated to it++; } } The code compiles and runs, but the students vector isn't adding any student structures to its front. My program's output displays that the students vector is unchanged. Here's my complete source code, followed by a sample input file (I redirect input from the console by typing " < grades" after the compiled program name at the command prompt.) #include <iostream> #include <string> #include <algorithm> // to get the declaration of `sort' #include <stdexcept> // to get the declaration of `domain_error' #include <vector> // to get the declaration of `vector' //driver program for grade partitioning examples using std::cin; using std::cout; using std::endl; using std::string; using std::domain_error; using std::sort; using std::vector; using std::max; using std::istream; struct Student_info { std::string name; double midterm, final; std::vector<double> homework; }; bool compare(const Student_info&, const Student_info&); std::istream& read(std::istream&, Student_info&); std::istream& read_hw(std::istream&, std::vector<double>&); double median(std::vector<double>); double grade(double, double, double); double grade(double, double, const std::vector<double>&); double grade(const Student_info&); bool fgrade(const Student_info&); void extract_fails(vector<Student_info>& v); int main() { vector<Student_info> vs; Student_info s; string::size_type maxlen = 0; while (read(cin, s)) { maxlen = max(maxlen, s.name.size()); vs.push_back(s); } sort(vs.begin(), vs.end(), compare); extract_fails(vs); // display the new, modified vector - it should be larger than // the input vector, due to some student structures being // added to the front of the vector. cout << "count: " << vs.size() << endl << endl; vector<Student_info>::iterator it = vs.begin(); while (it != vs.end()) cout << it++->name << endl; return 0; } // Extract the students who failed from the "students" vector. void extract_fails(vector<Student_info>& students) { typedef vector<Student_info>::size_type str_sz; typedef vector<Student_info>::iterator iter; iter it = students.begin(); str_sz i = 0, count = 0; while (it != students.end()) { // fgrade tests wether or not the student failed if (!fgrade(*it)) { // if student passed, copy to front of vector students.insert(students.begin(), it, it); // tracks of the number of passing students(so we can properly resize the array) count++; } cout << it->name << endl; // output to verify that each student is iterated to it++; } } bool compare(const Student_info& x, const Student_info& y) { return x.name < y.name; } istream& read(istream& is, Student_info& s) { // read and store the student's name and midterm and final exam grades is >> s.name >> s.midterm >> s.final; read_hw(is, s.homework); // read and store all the student's homework grades return is; } // read homework grades from an input stream into a `vector<double>' istream& read_hw(istream& in, vector<double>& hw) { if (in) { // get rid of previous contents hw.clear(); // read homework grades double x; while (in >> x) hw.push_back(x); // clear the stream so that input will work for the next student in.clear(); } return in; } // compute the median of a `vector<double>' // note that calling this function copies the entire argument `vector' double median(vector<double> vec) { typedef vector<double>::size_type vec_sz; vec_sz size = vec.size(); if (size == 0) throw domain_error("median of an empty vector"); sort(vec.begin(), vec.end()); vec_sz mid = size/2; return size % 2 == 0 ? (vec[mid] + vec[mid-1]) / 2 : vec[mid]; } // compute a student's overall grade from midterm and final exam grades and homework grade double grade(double midterm, double final, double homework) { return 0.2 * midterm + 0.4 * final + 0.4 * homework; } // compute a student's overall grade from midterm and final exam grades // and vector of homework grades. // this function does not copy its argument, because `median' does so for us. double grade(double midterm, double final, const vector<double>& hw) { if (hw.size() == 0) throw domain_error("student has done no homework"); return grade(midterm, final, median(hw)); } double grade(const Student_info& s) { return grade(s.midterm, s.final, s.homework); } // predicate to determine whether a student failed bool fgrade(const Student_info& s) { return grade(s) < 60; } Sample input file: Moo 100 100 100 100 100 100 100 100 Fail1 45 55 65 80 90 70 65 60 Moore 75 85 77 59 0 85 75 89 Norman 57 78 73 66 78 70 88 89 Olson 89 86 70 90 55 73 80 84 Peerson 47 70 82 73 50 87 73 71 Baker 67 72 73 40 0 78 55 70 Davis 77 70 82 65 70 77 83 81 Edwards 77 72 73 80 90 93 75 90 Fail2 55 55 65 50 55 60 65 60 Thanks to anyone who takes the time to look at this!

    Read the article

  • java applet stops running on exceptions

    - by Marius
    I've developed a simple applet that imports an image from the clipboard. When i run the class file from NetBeans, everything works fine. But when i try to run it as an applet ... it gives me lots of errors in the java console and does not run ... - The applet is signed - There is a static method in one class, called getImageFromClipboard(). When the applet runs, it calls this method. - getImageFromClipboard() method has a try-catch block and suppresses all errors. It simply returns either a BufferedImage or null. - When applet runs, it does some visual adjustments before calling getImageFromClipboard() Now the scenario is as follows: the class from netbeans runs, fails to import the image and adjusts the interface accordingly (displays an error in a label) But when i run it in a browser, java console is filled with errors and nothing after the getImageFromClipboard() line works. Although the applet itself loads and does everything it's supposed do do before importing the image. So why am i getting errors if i accept the certificate and all of the possible errors are in try-catch blocks? None of this code should throw any exceptions. Any ideas why this is happening? Or do you need to see the errors to tell? UPDATE I've managed to find out the problem myself. The class that i'm using is not in the jar file :( How do i add it in? I'm using "add jar folder" in netbeans on the libraries package to import it but it does not seem to get copied to the jar.

    Read the article

  • Some Async Socket Code - Help with Garbage Collection?

    - by divinci
    Hi all, I think this question is really about my understanding of Garbage collection and variable references. But I will go ahead and throw out some code for you to look at. // Please note do not use this code for async sockets, just to highlight my question // SocketTransport // This is a simple wrapper class that is used as the 'state' object // when performing Async Socket Reads/Writes public class SocketTransport { public Socket Socket; public byte[] Buffer; public SocketTransport(Socket socket, byte[] buffer) { this.Socket = socket; this.Buffer = buffer; } } // Entry point - creates a SocketTransport, then passes it as the state // object when Asyncly reading from the socket. public void ReadOne(Socket socket) { SocketTransport socketTransport_One = new SocketTransport(socket, new byte[10]); socketTransport_One.Socket.BeginRecieve ( socketTransport_One.Buffer, // Buffer to store data 0, // Buffer offset 10, // Read Length SocketFlags.None // SocketFlags new AsyncCallback(OnReadOne), // Callback when BeginRead completes socketTransport_One // 'state' object to pass to Callback. ); } public void OnReadOne(IAsyncResult ar) { SocketTransport socketTransport_One = ar.asyncState as SocketTransport; ProcessReadOneBuffer(socketTransport_One.Buffer); // Do processing // New Read // Create another! SocketTransport (what happens to first one?) SocketTransport socketTransport_Two = new SocketTransport(socket, new byte[10]); socketTransport_Two.Socket.BeginRecieve ( socketTransport_One.Buffer, 0, 10, SocketFlags.None new AsyncCallback(OnReadTwo), socketTransport_Two ); } public void OnReadTwo(IAsyncResult ar) { SocketTransport socketTransport_Two = ar.asyncState as SocketTransport; .............. So my question is: The first SocketTransport to be created (socketTransport_One) has a strong reference to a Socket object (lets call is ~SocketA~). Once the async read is completed, a new SocketTransport object is created (socketTransport_Two) also with a strong reference to ~SocketA~. Q1. Will socketTransport_One be collected by the garbage collector when method OnReadOne exits? Even though it still contains a strong reference to ~SocketA~ Thanks all!

    Read the article

  • phpUnit - mock php extended exception object

    - by awongh
    I'm testing some legacy code that extends the default php exception object. This code prints out a custom HTML error message. I would like to mock this exception object in such a way that when the tested code generates an exception it will just echo the basic message instead of giving me the whole HTML message. I cannot figure out a way to do this. It seems like you can test for explicit exceptions, but you can't change in a general way the behavior of an exception, and you also can't mock up an object that extends a default php functionality. ( can't think of another example of this beyond exceptions... but it would seem to be the case ) I guess the problem is, where would you attach the mocked object?? It seems like you can't interfere with 'throw new' and this is the place that the object method is called.... Or if you could somehow use the existing phpunit exception functionality to change the exception behavior the way you want, in a general way for all your code... but this seems like it would be hacky and bad....

    Read the article

  • Dealing with Try/Catch Exceptions in Java bytecode? ("stack height inconsistent")

    - by Cogwirrel
    I am trying to do some error handling in java bytecode. I first tried to implement some catch-like subroutines, where I would check for the error condition, and jump to the appropriate subroutine, a little like: iconst_1 iconst_0 dup ifeq calldiverr goto enddivtest calldiverr: jsr divError enddivtest: idiv ...More instructions... divError: getstatic java/lang/System/out Ljava/io/PrintStream; ldc "Oh dear you divided by 0!" invokevirtual java/io/PrintStream/print(Ljava/lang/String;)V The problem with the above is that when I have multiple instructions that jump to this subroutine, I get an error message when running the bytecode, saying that the stack height is inconsistent. Perhaps using exceptions is the best way to get around this? From some googling I have found that you can create instances of Exception classes and initialise them with something like: new java/lang/Exception dup ldc "exception message!" invokespecial java/lang/Exception/<init>(Ljava/lang/String;)V I have also found that you can throw them with athrow and this seems ok. What is confusing me however is exactly how exceptions are caught. There seems to be a magical "Exception table" which glues the throwing and catching of exceptions together, but I do not know how to define one of these when writing bytecode from scratch (and assembling using Jasmin). Can somebody tell me the secret of creating an exception table? And possibly give me an example of exception handling that will assemble with jasmin?

    Read the article

  • Managing Instances in Python

    - by BeensTheGreat
    Hello, I am new to Python and this is my first time asking a stackOverflow question, but a long time reader. I am working on a simple card based game but am having trouble managing instances of my Hand class. If you look below you can see that the hand class is a simple container for cards(which are just int values) and each Player class contains a hand class. However, whenever I create multiple instances of my Player class they all seem to manipulate a single instance of the Hand class. From my experience in C and Java it seems that I am somehow making my Hand class static. If anyone could help with this problem I would appreciate it greatly. Thank you, Thad To clarify: An example of this situation would be p = player.Player() p1 = player.Player() p.recieveCard(15) p1.recieveCard(21) p.viewHand() which would result in: [15,21] even though only one card was added to p Hand class: class Hand: index = 0 cards = [] #Collections of cards #Constructor def __init__(self): self.index self.cards def addCard(self, card): """Adds a card to current hand""" self.cards.append(card) return card def discardCard(self, card): """Discards a card from current hand""" self.cards.remove(card) return card def viewCards(self): """Returns a collection of cards""" return self.cards def fold(self): """Folds the current hand""" temp = self.cards self.cards = [] return temp Player Class import hand class Player: name = "" position = 0 chips = 0 dealer = 0 pHand = [] def __init__ (self, nm, pos, buyIn, deal): self.name = nm self.position = pos self.chips = buyIn self.dealer = deal self.pHand = hand.Hand() return def recieveCard(self, card): """Recieve card from the dealer""" self.pHand.addCard(card) return card def discardCard(self, card): """Throw away a card""" self.pHand.discardCard(card) return card def viewHand(self): """View the players hand""" return self.pHand.viewCards() def getChips(self): """Get the number of chips the player currently holds""" return self.chips def setChips(self, chip): """Sets the number of chips the player holds""" self.chips = chip return def makeDealer(self): """Makes this player the dealer""" self.dealer = 1 return def notDealer(self): """Makes this player not the dealer""" self.dealer = 0 return def isDealer(self): """Returns flag wether this player is the dealer""" return self.dealer def getPosition(self): """Returns position of the player""" return self.position def getName(self): """Returns name of the player""" return self.name

    Read the article

  • JPA native query join returns object but dereference throws class cast exception

    - by masato-san
    I'm using JPQL Native query to join table and query result is stored in List<Object[]>. public String getJoinJpqlNativeQuery() { String final SQL_JOIN = "SELECT v1.bitbit, v1.numnum, v1.someTime, t1.username, t1.anotherNum FROM MasatosanTest t1 JOIN MasatoView v1 ON v1.username = t1.username;" System.out.println("get join jpql native query is being called ============================"); EntityManager em = null; List<Object[]> out = null; try { em = EmProvider.getDefaultManager(); Query query = em.createNativeQuery(SQL_JOIN); out = query.getResultList(); System.out.println("return object ==========>" + out); System.out.println(out.get(0)); String one = out.get(0).toString(); //LINE 77 where ClassCastException System.out.println(one); } catch(Exception e) { } finally { if(em != null) { em.close; } } } The problem is System.out.println("return object ==========>" + out); outputs: return object ==========> [[true, 0, 2010-12-21 15:32:53.0, masatosan, 0.020], [false, 0, 2010-12-21 15:32:53.0, koga, 0.213]] System.out.println(out.get(0)) outputs: [true, 0, 2010-12-21 15:32:53.0, masatosan, 0.020] So I assumed that I can assign return value of out.get(0) which should be String: String one = out.get(0).toString(); But I get weird ClassCastException. java.lang.ClassCastException: java.util.Vector cannot be cast to [Ljava.lang.Object; at local.test.jaxrs.MasatosanTestResource.getJoinJpqlNativeQuery (MasatosanTestResource.java:77) So what's really going on? Even Object[] foo = out.get(0); would throw an ClassCastException :(

    Read the article

  • iPhone application update (using Core Data on Sqlite)

    - by owen
    I have an app which is using Core Data on Sqlite, Now I have a update which has some DB structure changes say adding a new table I know when an app get updated, it updates the app binary only, nothing on document directory will be changed. When the app gets updated and launchs at the first time and run [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:[self managedObjectModel]]; It will find the difference between the data model and DB structure in Sqlite and will throw an exception and quit. Error: "The model used to open the store is incompatible with the one used to create the store" So, can anyone here give me some idea how to update an app when there is a DB structure change? I think we can run a DB script to create that new table when it launchs the update at the first time. But if there are other changes like changing the type of some fields or deleting some fields, and we need to migrate the old data, this is really a headache. In this case, Is the only way to do is creating a new app? Is there anyone tried something similar like this?

    Read the article

  • BWToolkit inclusion crashing

    - by Schroedinger
    Hey guys I'm using the latest version of XCode (3.2.2) and I've linked the framework using the tutorial. I was building my app and tested it and I get a BWToolkit exception on decoding. I've included the Framework in the frameworks and added it to the copy files stage. I even created a new dummy app including the framework and adding it to the copy files stage and it still crashes when I try to run. Any ideas? Do I need to include it somewhere in the app? I'm worried I've overlooked something really simple. 2010-04-13 14:14:24.540 BWTestFramework[7504:a0f] An uncaught exception was raised 2010-04-13 14:14:24.543 BWTestFramework[7504:a0f] *** -[NSKeyedUnarchiver decodeObjectForKey:]: cannot decode object of class (BWSplitView) 2010-04-13 14:14:24.545 BWTestFramework[7504:a0f] *** Terminating app due to uncaught exception 'NSInvalidUnarchiveOperationException', reason: '*** -[NSKeyedUnarchiver decodeObjectForKey:]: cannot decode object of class (BWSplitView)' *** Call stack at first throw: ( 0 CoreFoundation 0x00007fff84a77d24 __exceptionPreprocess + 180 1 libobjc.A.dylib 0x00007fff82ba00f3 objc_exception_throw + 45 2 CoreFoundation 0x00007fff84a77b47 +[NSException raise:format:arguments:] + 103 3 CoreFoundation 0x00007fff84a77ad4 +[NSException raise:format:] + 148 4 Foundation 0x00007fff83804aa6 _decodeObjectBinary + 2427 5 Foundation 0x00007fff83805825 -[NSKeyedUnarchiver _decodeArrayOfObjectsForKey:] + 1229 6 Foundation 0x00007fff83805d65 -[NSArray(NSArray) initWithCoder:] + 462 7 Foundation 0x00007fff83804b1f _decodeObjectBinary + 2548 8 Foundation 0x00007fff83803f99 _decodeObject + 208 9 AppKit 0x00007fff8069fbfb -[NSView initWithCoder:] + 362 10 Foundation 0x00007fff83804b1f _decodeObjectBinary + 2548 11 Foundation 0x00007fff83803f99 _decodeObject + 208 12 AppKit 0x00007fff806adfbb -[NSWindowTemplate initWithCoder:] + 3824 13 Foundation 0x00007fff83804b1f _decodeObjectBinary + 2548 14 Foundation 0x00007fff83805825 -[NSKeyedUnarchiver _decodeArrayOfObjectsForKey:] + 1229 15 Foundation 0x00007fff83805268 -[NSSet(NSSet) initWithCoder:] + 447 16 Foundation 0x00007fff83804b1f _decodeObjectBinary + 2548 17 Foundation 0x00007fff83803f99 _decodeObject + 208 18 AppKit 0x00007fff8062fcde -[NSIBObjectData initWithCoder:] + 1983 19 Foundation 0x00007fff83804b1f _decodeObjectBinary + 2548 20 Foundation 0x00007fff83803f99 _decodeObject + 208 21 AppKit 0x00007fff8062f40d loadNib + 146 22 AppKit 0x00007fff8062e96d +[NSBundle(NSNibLoading) _loadNibFile:nameTable:withZone:ownerBundle:] + 248 23 AppKit 0x00007fff8062e7a5 +[NSBundle(NSNibLoading) loadNibNamed:owner:] + 326 24 AppKit 0x00007fff8062bd27 NSApplicationMain + 279 25 BWTestFramework 0x0000000100001891 main + 33 26 BWTestFramework 0x0000000100001868 start + 52 ) terminate called after throwing an instance of 'NSException' That's the crash report

    Read the article

  • What are the best workarounds for known problems with Hibernate's schema validation of floating poin

    - by Jason Novak
    I have several Java classes with double fields that I am persisting via Hibernate. For example, I have @Entity public class Node ... private double value; When Hibernate's org.hibernate.dialect.Oracle10gDialect creates the DDL for the Node table, it maps the value field to a "double precision" type. create table MDB.Node (... value double precision not null, ... It would appear that in Oracle, "double precision" is an alias for "float". So, when I try to verify the database schema using the org.hibernate.cfg.AnnotationConfiguration.validateSchema() method, Oracle appears to describe the value column as a "float". This causes Hibernate to throw the following Exception org.hibernate.HibernateException: Wrong column type in DBO.ACL_RULE for column value. Found: float, expected: double precision A very similar problem is listed in Hibernate's JIRA database as HHH-1961 (http://opensource.atlassian.com/projects/hibernate/browse/HHH-1961). I'd like to avoid doing anything that will break MySql, Postgres, and Sql Server support so extending the Oracle10gDialect appears to be the most promising of the workarounds mentioned in HHH-1961. But extending a Dialect is something I've never done before and I'm afraid there may be some nasty gotchas. What is the best workaround for this problem that won't break our compatibility with MySql, Postgres, and Sql Server? Thanks for taking the time to look at this!

    Read the article

  • How to make a thread that runs at x:00 x:15 x:30 and x:45 do something different at 2:00.

    - by rmarimon
    I have a timer thread that needs to run at a particular moments of the day to do an incremental replication with a database. Right now it runs at the hour, 15 minutes past the hour, 30 minutes past the hour and 45 minutes past the hour. This is the code I have which is working ok: public class TimerRunner implements Runnable { private static final Semaphore lock = new Semaphore(1); private static final ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor(); public static void initialize() { long delay = getDelay(); executor.schedule(new TimerRunner(), delay, TimeUnit.SECONDS); } public static void destroy() { executor.shutdownNow(); } private static long getDelay() { Calendar now = Calendar.getInstance(); long p = 15 * 60; // run at 00, 15, 30 and 45 minutes past the hour long second = now.get(Calendar.MINUTE) * 60 + now.get(Calendar.SECOND); return p - (second % p); } public static void replicate() { if (lock.tryAcquire()) { try { Thread t = new Thread(new Runnable() { public void run() { try { // here is where the magic happens } finally { lock.release(); } } }); t.start(); } catch (Exception e) { lock.release(); } } else { throw new IllegalStateException("already running a replicator"); } } public void run() { try { TimerRunner.replicate(); } finally { long delay = getDelay(); executor.schedule(new TimerRunner(), delay, TimeUnit.SECONDS); } } } This process is started by calling TimerRunner.initialize() when a server starts and calling TimerRunner.destroy(). I have created a full replication process (as opposed to incremental) that I would like to run at a certain moment of the day, say 2:00am. How would change the above code to do this? I think that it should be very simple something like if it is now around 2:00am and it's been a long time since I did the full replication then do it now, but I can't get the if right. Beware that sometimes the replicate process takes way longer to complete. Sometimes beyond the 15 minutes, posing a problem in running at around 2:00am.

    Read the article

  • Is Form validation and Business validation too much?

    - by Robert Cabri
    I've got this question about form validation and business validation. I see a lot of frameworks that use some sort of form validation library. You submit some values and the library validates the values from the form. If not ok it will show some errors on you screen. If all goes to plan the values will be set into domain objects. Here the values will be or, better said, should validated (again). Most likely the same validation in the validation library. I know 2 PHP frameworks having this kind of construction Zend/Kohana. When I look at programming and some principles like Don't Repeat Yourself (DRY) and single responsibility principle (SRP) this isn't a good way. As you can see it validates twice. Why not create domain objects that do the actual validation. Example: Form with username and email form is submitted. Values of the username field and the email field will be populated in 2 different Domain objects: Username and Email class Username {} class Email {} These objects validate their data and if not valid throw an exception. Do you agree? What do you think about this aproach? Is there a better way to implement validations? I'm confused about a lot of frameworks/developers handling this stuff. Are they all wrong or am I missing a point? Edit: I know there should also be client side kind of validation. This is a different ballgame in my Opinion. If You have some comments on this and a way to deal with this kind of stuff, please provide.

    Read the article

  • ArrayAccess multidimensional (un)set?

    - by anomareh
    I have a class implementing ArrayAccess and I'm trying to get it to work with a multidimensional array. exists and get work. set and unset are giving me a problem though. class ArrayTest implements ArrayAccess { private $_arr = array( 'test' => array( 'bar' => 1, 'baz' => 2 ) ); public function offsetExists($name) { return isset($this->_arr[$name]); } public function offsetSet($name, $value) { $this->_arr[$name] = $value; } public function offsetGet($name) { return $this->_arr[$name]; } public function offsetUnset($name) { unset($this->_arr[$name]); } } $arrTest = new ArrayTest(); isset($arrTest['test']['bar']); // Returns TRUE echo $arrTest['test']['baz']; // Echo's 2 unset($arrTest['test']['bar']; // Error $arrTest['test']['bar'] = 5; // Error I know $_arr could just be made public so you could access it directly, but for my implementation it's not desired and is private. The last 2 lines throw an error: Notice: Indirect modification of overloaded element. I know ArrayAccess just generally doesn't work with multidimensional arrays, but is there anyway around this or any somewhat clean implementation that will allow the desired functionality? The best idea I could come up with is using a character as a separator and testing for it in set and unset and acting accordingly. Though this gets really ugly really fast if you're dealing with a variable depth. Does anyone know why exists and get work so as to maybe copy over the functionality? Thanks for any help anyone can offer.

    Read the article

  • Null Safe dereferencing in Java like ?. in Groovy using Maybe monad

    - by Sathish
    I'm working on a codebase ported from Objective C to Java. There are several usages of method chaining without nullchecks dog.collar().tag().name() I was looking for something similar to safe-dereferencing operator ?. in Groovy instead of having nullchecks dog.collar?.tag?.name This led to Maybe monad to have the notion of Nothing instead of Null. But all the implementations of Nothing i came across throw exception when value is accessed which still doesn't solve the chaining problem. I made Nothing return a mock, which behaves like NullObject pattern. But it solves the chaining problem. Is there anything wrong with this implementation of Nothing? [http://github.com/sathish316/jsafederef/blob/master/src/s2k/util/safederef/Nothing.java] As far as i can see 1. It feels odd to use mocking library in code 2. It doesn't stop at the first null. 3. How do i distinguish between null result because of null reference or name actually being null? How is it distinguished in Groovy code?

    Read the article

  • Why can't I include these data files in a Python distribution using distutils?

    - by froadie
    I'm writing a setup.py file for a Python project so that I can distribute it. The aim is to eventually create a .egg file, but I'm trying to get it to work first with distutils and a regular .zip. This is an eclipse pydev project and my file structure is something like this: ProjectName src somePackage module1.py module2.py ... config propsFile1.ini propsFile2.ini propsFile3.ini setup.py Here's my setup.py code so far: from distutils.core import setup setup(name='ProjectName', version='1.0', packages=['somePackage'], data_files = [('config', ['..\config\propsFile1.ini', '..\config\propsFile2.ini', '..\config\propsFile3.ini'])] ) When I run this (with sdist as a command line parameter), a .zip file gets generated with all the python files - but the config files are not included. I thought that this code: data_files = [('config', ['..\config\propsFile1.ini', '..\config\propsFile2.ini', '..\config\propsFile3.ini'])] indicates that those 3 specified config files should be copied to a "config" directory in the zip distribution. Why is this code not accomplishing anything? What am I doing wrong? (I have also tried playing around with the paths of the config files... But nothing seems to help. Would Python throw an error or warning if the path was incorrect / file was not found?)

    Read the article

  • Transitioning from FlexBuilder 3 to FlashBuilder 4 ... there and back again.

    - by Robusto
    It's growing pains time again. Some of our stuff requires FlashBuilder 4 and some still requires FlexBuilder 3. Both are installed OK, and no projects use both IDEs. The trouble is, when I go back to work on a FlexBuilder 3 project it takes freakin' forever to build and I get weird errors like these: This doesn't seem to cause any identifiable problems except to throw up a modal dialog at various points in the build process, forcing user interaction. But I do notice that memory fills up fast in FB3 and generally FB3 starts behaving strangely and ultimately quits once it gets up over 700MB. This is only a temporary bridge situation until we get all projects into FB4, but "temporary" could mean weeks if not months. Does anyone have any advice for how to get through this bridge period? Is there anything I can do to make these two IDEs work and play well together? Failing that, does anyone know what "java.lang.String" is the "reason" for the problem? Does Eclipse have a resource bundle somewhere that is getting corrupted when i go back and forth between the two?

    Read the article

  • When is someone else's code I use from the internet "mine"?

    - by robault
    I'm building a library from methods that I've found on the internet. Some are free to use or modify with no requirements, others say that if I leave a comment in the code it's okay to use, others say when I use the code I have to attribute the use of someone's code in my application (in the credits for my app I guess). What I've been doing is reorganizing classes, renaming methods, adding descriptions (code comments), renaming the parameters and names inside the methods to something meaningful, optimizing loops if applicable, changing return types, adding try/catch/throw blocks, adding parameter checks and cleaning up resources in the methods. For example; I didn't come up with the algorithm for blurring a Bitmap but I've taken the basic example of iterating through the pixels and turned it into a decent library method (applying the aforementioned modifications). I understand how to go about building it now myself but I didn't actually hit the keystrokes to make it and I couldn't have come up with it before learning from their example. What about code people get in answers on Stackoverflow or examples from Codeproject? At what point can I drop their requirements because at n% their code became mine? FWIW I intend on using the libraries to create products that I will sell.

    Read the article

  • Rhino Mocks Partial Mock

    - by dotnet crazy kid
    I am trying to test the logic from some existing classes. It is not possible to re-factor the classes at present as they are very complex and in production. What I want to do is create a mock object and test a method that internally calls another method that is very hard to mock. So I want to just set a behaviour for the secondary method call. But when I setup the behaviour for the method, the code of the method is invoked and fails. Am I missing something or is this just not possible to test without re-factoring the class? I have tried all the different mock types (Strick,Stub,Dynamic,Partial ect.) but they all end up calling the method when I try to set up the behaviour. using System; using MbUnit.Framework; using Rhino.Mocks; namespace MMBusinessObjects.Tests { [TestFixture] public class PartialMockExampleFixture { [Test] public void Simple_Partial_Mock_Test() { const string param = "anything"; //setup mocks MockRepository mocks = new MockRepository(); var mockTestClass = mocks.StrictMock<TestClass>(); //record beahviour *** actualy call into the real method stub *** Expect.Call(mockTestClass.MethodToMock(param)).Return(true); //never get to here mocks.ReplayAll(); //this is what i want to test Assert.IsTrue(mockTestClass.MethodIWantToTest(param)); } public class TestClass { public bool MethodToMock(string param) { //some logic that is very hard to mock throw new NotImplementedException(); } public bool MethodIWantToTest(string param) { //this method calls the if( MethodToMock(param) ) { //some logic i want to test } return true; } } } }

    Read the article

  • PHP: Exception not caught by try ... catch

    - by Christian Brenner
    I currently am working on an autoloader class for one of my projects. Below is the code for the controller library: public static function includeFileContainingClass($classname) { $classname_rectified = str_replace(__NAMESPACE__.'\\', '', $classname); $controller_path = ENVIRONMENT_DIRECTROY_CONTROLLERS.strtolower($classname_rectified).'.controller.php'; if (file_exists($controller_path)) { include $controller_path; return true; } else { // TODO: Implement gettext('MSG_FILE_CONTROLLER_NOTFOUND') throw new Exception('File '.strtolower($classname_rectified).'.controller.php not found.'); return false; } } And here's the code of the file I try to invoke the autoloader on: try { spl_autoload_register(__NAMESPACE__.'\\Controller::includeFileContainingClass'); } catch (Exception $malfunction) { die($malfunction->getMessage()); } // TESTING ONLY $test = new Testing(); When I try to force a malfunction, I get the following message: Fatal error: Uncaught exception 'Exception' with message 'File testing.controller.php not found.' in D:\cerophine-0.0.1-alpha1\application\libraries\controller.library.php:51 Stack trace: #0 [internal function]: application\Controller::includeFileContainingClass('application\Tes...') #1 D:\cerophine-0.0.1-alpha1\index.php(58): spl_autoload_call('application\Tes...') #2 {main} thrown in D:\cerophine-0.0.1-alpha1\application\libraries\controller.library.php on line 51 What seems to be wrong?

    Read the article

  • How would you code a washing machine?

    - by Dan
    Imagine I have a class that represents a simple washing machine. It can perform following operations in the following order: turn on - wash - centrifuge - turn off. I see two basic alternatives: A) I can have a class WashingMachine with methods turnOn(), wash(int minutes), centrifuge(int revs), turnOff(). The problem with this is that the interface says nothing about the correct order of operations. I can at best throw InvalidOprationException if the client tries to centrifuge before machine was turned on. B) I can let the class itself take care of correct transitions and have the single method nextOperation(). The problem with this on the other hand, is that the semantics is poor. Client will not know what will happen when he calls the nextOperation(). Imagine you implement the centrifuge button’s click event so it calls nextOperation(). User presses the centrifuge button after machine was turned on and ups! machine starts to wash. I will probably need a few properties on my class to parameterize operations, or maybe a separate Program class with washLength and centrifugeRevs fields, but that is not really the problem. Which alternative is better? Or maybe there are some other, better alternatives that I missed to describe?

    Read the article

  • How to append a row to a TableViewSection in Titanium?

    - by Mike Trpcic
    I'm developing an iPhone application in Titanium, and need to append a row to a particular TableViewSection. I can't do this on page load, as it's done dynamically by the user throughout the lifecycle of the application. The documentation says that the TableViewSection has an add method which takes two arguments, but I can't make it work. Here's my existing code: for(var i = 0; i <= product_count; i++){ productsTableViewSection.add( Ti.UI.createTableViewRow({ title:'Testing...' }) ); } That is just passing one argument in, and that causes Titanium to die with an uncaught exception: 2010-04-26 16:57:18.056 MyApplication[72765:207] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Invalid update: invalid number of rows in section 2. The number of rows contained in an existing section after the update (2) must be equal to the number of rows contained in that section before the update (1), plus or minus the number of rows inserted or deleted from that section (0 inserted, 0 deleted).' 2010-04-26 16:57:18.056 MyApplication[72765:207] Stack: ( The exception looks like it did add the row, but it's not allowed to for some reason. Since the documentation says that TableViewSection takes in "view" and "row", I tried the following: for(var i = 0; i <= product_count; i++){ productsTableViewSection.add( Ti.UI.createView({}), Ti.UI.createTableViewRow({ title:'Testing...' }) ); } The above code doesn't throw the exception, but it gives a [WARN]: [WARN] Invalid type passed to function. expected: TiUIViewProxy, was: TiUITableViewRowProxy in -[TiUITableViewSectionProxy add:] (TiUITableViewSectionProxy.m:62) TableViewSections don't seem to support any methods like appendRow, or insertRow, so I don't know where else to go with this. I've looked through the KitchenSink app, but there are no examples that I could find of adding a row to a TableViewSection. Any help is appreciated.

    Read the article

  • How to simulate OutOfMemory exception

    - by Gacek
    I need to refactor my project in order to make it immune to OutOfMemory exception. There are huge collections used in my project and by changing one parameter I can make my program to be more accurate or use less of the memory... OK, that's the background. What I would like to do is to run the routines in a loop: Run the subroutines with the default parameter. Catch the OutOfMemory exception, change the parameter and try to run it again. Do the 2nd point until parameters allow to run the subroutines without throwing the exception (usually, there will be only one change needed). Now, I would like to test it. I know, that I can throw the OutOfMemory exception on my own, but I would like to simulate some real situation. So the main question is: Is there a way of setting some kind of memory limit for my program, after reaching which the OutOfMemory exception will be thrown automatically? For example, I would like to set a limit, let's say 400MB of memory for my whole program to simulate the situation when there is such an amount of memory available in the system. Can it be done?

    Read the article

  • "pushModalScreen called by a non-event thread" thrown on event thread

    - by JGWeissman
    I am trying to get my Blackberry application to display a custom modal dialog, and have the opening thread wait until the user closes the dialog screen. final Screen dialog = new FullScreen(); ...// Fields are added to dialog Application.getApplication().invokeAndWait(new Runnable() { public void run() { Application.getUiApplication().pushModalScreen(dialog); } }); This is throwing an Exception which says "pushModalScreen called by a non-event thread" despite the fact that I am using invokeAndWait to call pushModalScreen from the event thread. Any ideas about what the real problem is? Here is the code to duplicate this problem: package com.test; import net.rim.device.api.ui.*; import net.rim.device.api.ui.component.*; import net.rim.device.api.ui.container.*; public class Application extends UiApplication { public static void main(String[] args) { new Application(); } private Application() { new Thread() { public void run() { Application.this.enterEventDispatcher(); } }.start(); final Screen dialog = new FullScreen(); final ButtonField closeButton = new ButtonField("Close Dialog"); closeButton.setChangeListener(new FieldChangeListener() { public void fieldChanged(Field field, int context) { Application.getUiApplication().popScreen(dialog); } }); dialog.add(closeButton); Application.getApplication().invokeAndWait(new Runnable() { public void run() { try { Application.getUiApplication().pushModalScreen(dialog); } catch (Exception e) { // To see the Exception in the debugger throw new RuntimeException(e.getMessage()); } } }); System.exit(0); } } I am using Component Package version 4.5.0.

    Read the article

  • .NET Speech recognition plugin Runtime Error: Unhandled Exception. What could possibly cause it?

    - by manuel
    I'm writing a plugin (dll file) for speech recognition, and I'm creating a WinForm as its interface/dialog. When I run the plugin and click the 'Speak' to start the initialization, I get an unhandled exception. Here is a piece of the code: public ref class Dialog : public System::Windows::Forms::Form { public: SpeechRecognitionEngine^ sre; private: System::Void btnSpeak_Click(System::Object^ sender, System::EventArgs^ e) { Initialize(); } protected: void Initialize() { if (System::Threading::Thread::CurrentThread->GetApartmentState() != System::Threading::ApartmentState::STA) { throw gcnew InvalidOperationException("UI thread required"); } //create the recognition engine sre = gcnew SpeechRecognitionEngine(); //set our recognition engine to use the default audio device sre->SetInputToDefaultAudioDevice(); //create a new GrammarBuilder to specify which commands we want to use GrammarBuilder^ grammarBuilder = gcnew GrammarBuilder(); //append all the choices we want for commands. //we want to be able to move, stop, quit the game, and check for the cake. grammarBuilder->Append(gcnew Choices("play", "stop")); //create the Grammar from th GrammarBuilder Grammar^ customGrammar = gcnew Grammar(grammarBuilder); //unload any grammars from the recognition engine sre->UnloadAllGrammars(); //load our new Grammar sre->LoadGrammar(customGrammar); //add an event handler so we get events whenever the engine recognizes spoken commands sre->SpeechRecognized += gcnew EventHandler<SpeechRecognizedEventArgs^> (this, &Dialog::sre_SpeechRecognized); //set the recognition engine to keep running after recognizing a command. //if we had used RecognizeMode.Single, the engine would quite listening after //the first recognized command. sre->RecognizeAsync(RecognizeMode::Multiple); //this->init(); } void sre_SpeechRecognized(Object^ sender, SpeechRecognizedEventArgs^ e) { //simple check to see what the result of the recognition was if (e->Result->Text == "play") { MessageBox(plugin.hwndParent, L"play", 0, 0); } if (e->Result->Text == "stop") { MessageBox(plugin.hwndParent, L"stop", 0, 0); } } };

    Read the article

  • What are the use cases for this static reflection code?

    - by Maslow
    This is Oliver Hanappi's static reflection code he posted on stackoverflow private static string GetMemberName(Expression expression) { switch (expression.NodeType) { case ExpressionType.MemberAccess: var memberExpression = (MemberExpression)expression; var supername = GetMemberName(memberExpression.Expression); if (String.IsNullOrEmpty(supername)) return memberExpression.Member.Name; return String.Concat(supername, '.', memberExpression.Member.Name); case ExpressionType.Call: var callExpression = (MethodCallExpression)expression; return callExpression.Method.Name; case ExpressionType.Convert: var unaryExpression = (UnaryExpression)expression; return GetMemberName(unaryExpression.Operand); case ExpressionType.Parameter: return String.Empty; default: throw new ArgumentException("The expression is not a member access or method call expression"); } } I have the public wrapper methods: public static string Name<T>(Expression<Action<T>> expression) { return GetMemberName(expression.Body); } public static string Name<T>(Expression<Func<T, object>> expression) { return GetMemberName(expression.Body); } then added my own method shortcuts public static string ClassMemberName<T>(this T sourceType,Expression<Func<T,object>> expression) { return GetMemberName(expression.Body); } public static string TMemberName<T>(this IEnumerable<T> sourceList, Expression<Func<T,object>> expression) { return GetMemberName(expression.Body); } What are examples of code that would necessitate or take advantage of the different branches in the GetMemberName(Expression expression) switch? what all is this code capable of making strongly typed?

    Read the article

< Previous Page | 118 119 120 121 122 123 124 125 126 127 128 129  | Next Page >