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• A xml schema created by "Schemagen" of Ant task can customize any more ?

  - by Take

  Now, I have two Java classes like this. public class HogeDomain { private User userDomain; public HogeDomain() { } and getter/setter.. } public class User { public User() { } private String id; private String password; private Date userDate; and getter/setter.. } And then, I created a xml schema above for using "Schemagen" of an Ant task automatically. It's this. <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <xs:schema version="1.0" xmlns:xs="http://www.w3.org/2001/XMLSchema"> <xs:complexType name="hogeDomain"> <xs:sequence> <xs:element name="userDomain" type="user" minOccurs="0"/> </xs:sequence> </xs:complexType> <xs:complexType name="user"> <xs:sequence> <xs:element name="id" type="xs:string" minOccurs="0"/> <xs:element name="password" type="xs:string" minOccurs="0"/> <xs:element name="userDate" type="xs:dateTime" minOccurs="0"/> </xs:sequence> </xs:complexType> </xs:schema> But I really want to create a xml schema like this to using JAXB marshalling or unmarshalling. <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <xs:schema version="1.0" xmlns:xs="http://www.w3.org/2001/XMLSchema"> <xs:complexType name="hogeDomain"> <xs:sequence> <xs:element name="userDomain" type="user" minOccurs="0"/> </xs:sequence> </xs:complexType> <xs:element name="user"> <xs:complexType> <xs:sequence> <xs:element name="id" type="xs:string" minOccurs="0"/> <xs:element name="password" type="xs:string" minOccurs="0"/> <xs:element name="userDate" type="xs:dateTime" minOccurs="0"/> </xs:sequence> </xs:complexType> </xs:element> </xs:schema> How to create this xml schema for using a "Schemagen" Ant task ? I don't want to write a xml schema for hand-made. And is there any solutions when if it can't ?

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• When does logic belong in the Business Object/Entity, and when does it belong in a Service?

  - by Casey

  In trying to understand Domain Driven Design I keep returning to a question that I can't seem to definitively answer. How do you determine what logic belongs to a Domain entity, and what logic belongs to a Domain Service? Example: We have an Order class for an online store. This class is an entity and an aggregate root (it contains OrderItems). Public Class Order:IOrder { Private List<IOrderItem> OrderItems Public Order(List<IOrderItem>) { OrderItems = List<IOrderItem> } Public Decimal CalculateTotalItemWeight() //This logic seems to belong in the entity. { Decimal TotalWeight = 0 foreach(IOrderItem OrderItem in OrderItems) { TotalWeight += OrderItem.Weight } return TotalWeight } } I think most people would agree that CalculateTotalItemWeight belongs on the entity. However, at some point we have to ship this order to the customer. To accomplish this we need to do two things: 1) Determine the postage rate necessary to ship this order. 2) Print a shipping label after determining the postage rate. Both of these actions will require dependencies that are outside the Order entity, such as an external webservice to retrieve postage rates. How should we accomplish these two things? I see a few options: 1) Code the logic directly in the domain entity, like CalculateTotalItemWeight. We then call: Order.GetPostageRate Order.PrintLabel 2) Put the logic in a service that accepts IOrder. We then call: PostageService.GetPostageRate(Order) PrintService.PrintLabel(Order) 3) Create a class for each action that operates on an Order, and pass an instance of that class to the Order through Constructor Injection (this is a variation of option 1 but allows reuse of the RateRetriever and LabelPrinter classes): Public Class Order:IOrder { Private List<IOrderItem> OrderItems Private RateRetriever _Retriever Private LabelPrinter _Printer Public Order(List<IOrderItem>, RateRetriever Retriever, LabelPrinter Printer) { OrderItems = List<IOrderItem> _Retriever = Retriever _Printer = Printer } Public Decimal GetPostageRate { _Retriever.GetPostageRate(this) } Public void PrintLabel { _Printer.PrintLabel(this) } } Which one of these methods do you choose for this logic, if any? What is the reasoning behind your choice? Most importantly, is there a set of guidelines that led you to your choice?

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• Is throwing an exception a healthy way to exit?

  - by ramaseshan

  I have a setup that looks like this. class Checker { // member data Results m_results; // see below public: bool Check(); private: bool Check1(); bool Check2(); // .. so on }; Checker is a class that performs lengthy check computations for engineering analysis. Each type of check has a resultant double that the checker stores. (see below) bool Checker::Check() { // initilisations etc. Check1(); Check2(); // ... so on } A typical Check function would look like this: bool Checker::Check1() { double result; // lots of code m_results.SetCheck1Result(result); } And the results class looks something like this: class Results { double m_check1Result; double m_check2Result; // ... public: void SetCheck1Result(double d); double GetOverallResult() { return max(m_check1Result, m_check2Result, ...); } }; Note: all code is oversimplified. The Checker and Result classes were initially written to perform all checks and return an overall double result. There is now a new requirement where I only need to know if any of the results exceeds 1. If it does, subsequent checks need not be carried out(it's an optimisation). To achieve this, I could either: Modify every CheckN function to keep check for result and return. The parent Check function would keep checking m_results. OR In the Results::SetCheckNResults(), throw an exception if the value exceeds 1 and catch it at the end of Checker::Check(). The first is tedious, error prone and sub-optimal because every CheckN function further branches out into sub-checks etc. The second is non-intrusive and quick. One disadvantage is I can think of is that the Checker code may not necessarily be exception-safe(although there is no other exception being thrown anywhere else). Is there anything else that's obvious that I'm overlooking? What about the cost of throwing exceptions and stack unwinding? Is there a better 3rd option?

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• Can't record or play with a simple recorder?

  - by user1280535

  I have 2 classes, a record and a player. In my main scene, I create an instance of them and play and record. But, as I see, it only records and somehow does not play (the file is not there!) Here is the code for both : -(void)record { NSArray *dirPaths; NSString *docsDir; NSString *sound= @"sound0.caf" ; dirPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) ; docsDir = [dirPaths objectAtIndex:0]; NSString *soundFilePath = [docsDir stringByAppendingPathComponent:sound]; NSURL *soundFileURL = [NSURL fileURLWithPath:soundFilePath]; NSDictionary *settings = [NSDictionary dictionaryWithObjectsAndKeys: [NSNumber numberWithFloat: 44100.0], AVSampleRateKey, [NSNumber numberWithInt: kAudioFormatAppleLossless], AVFormatIDKey, [NSNumber numberWithInt: 1], AVNumberOfChannelsKey, [NSNumber numberWithInt: AVAudioQualityMax], AVEncoderAudioQualityKey, nil]; NSError *error; myRecorder = [[AVAudioRecorder alloc] initWithURL:soundFileURL settings:settings error:&error]; if (myRecorder) { NSLog(@"rec"); [myRecorder prepareToRecord]; myRecorder.meteringEnabled = YES; [myRecorder record]; } else NSLog( @"error" ); } I can see the log of rec. -(void)play { NSArray *dirPaths; NSString *docsDir; dirPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); docsDir = [dirPaths objectAtIndex:0]; NSString *soundFilePath1 = @"sound0.caf" ; NSURL *soundFileURL = [NSURL fileURLWithPath:soundFilePath1]; BOOL isMyFileThere = [[NSFileManager defaultManager] fileExistsAtPath:soundFilePath1]; if(isMyFileThere) { NSLog(@"PLAY"); avPlayer1 = [[AVAudioPlayer alloc] initWithContentsOfURL:soundFileURL error:NULL]; avPlayer1.volume = 8.0; avPlayer1.delegate = self; [avPlayer1 play]; } } I DONT SEE THE LOG OF PLAY ! I call them both with: recInst=[recorder alloc]; //to rec [recInst record]; plyInst=[player alloc]; //play [plyInst play]; and to stop the recorder: - (void)stopRecorder { NSLog(@"stopRecordings"); [myRecorder stop]; //[myRecorder release]; } What's wrong here? Thanks.

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• How to properly mix generics and inheritance to get the desired result?

  - by yamsha

  My question is not easy to explain using words, fortunately it's not too difficult to demonstrate. So, bear with me: public interface Command<R> { public R execute();//parameter R is the type of object that will be returned as the result of the execution of this command } public abstract class BasicCommand<R> { } public interface CommandProcessor<C extends Command<?>> { public <R> R process(C<R> command);//this is my question... it's illegal to do, but you understand the idea behind it, right? } //constrain BasicCommandProcessor to commands that subclass BasicCommand public class BasicCommandProcessor implements CommandProcessor<C extends BasicCommand<?>> { //here, only subclasses of BasicCommand should be allowed as arguments but these //BasicCommand object should be parameterized by R, like so: BasicCommand<R> //so the method signature should really be // public <R> R process(BasicCommand<R> command) //which would break the inheritance if the interface's method signature was instead: // public <R> R process(Command<R> command); //I really hope this fully illustrates my conundrum public <R> R process(C<R> command) { return command.execute(); } } public class CommandContext { public static void main(String... args) { BasicCommandProcessor bcp = new BasicCommandProcessor(); String textResult = bcp.execute(new BasicCommand<String>() { public String execute() { return "result"; } }); Long numericResult = bcp.execute(new BasicCommand<Long>() { public Long execute() { return 123L; } }); } } Basically, I want the generic "process" method to dictate the type of generic parameter of the Command object. The goal is to be able to restrict different implementations of CommandProcessor to certain classes that implement Command interface and at the same time to able to call the process method of any class that implements the CommandProcessor interface and have it return the object of type specified by the parametarized Command object. I'm not sure if my explanation is clear enough, so please let me know if further explanation is needed. I guess, the question is "Would this be possible to do, at all?" If the answer is "No" what would be the best work-around (I thought of a couple on my own, but I'd like some fresh ideas)

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• How do I access the enumerated item with an indexer and assign array string to it for display?

  - by g00p3k

  EDITED: Updated 3/23/09. See rest of post at bottom. I'm still having trouble with the indexer. Anymore help or examples would really help me out. Write a class, MyCourses, that contains an enumeration of all the courses that you are currently taking. This enum should be nested inside of your class MyCourses. Your class should also have an array field that provides a short description (as a String) of each of your courses. Write an indexer that takes one of your enumerated courses as an index and returns the String description of the course. Write a class MyFriends that contains an indexer that provides access to the names of your friends. namespace IT274_Unit4Project { public class MyCourses { // enumeration that contains an enumeration of all the courses that // student is currently enrolled in public enum CourseName {IT274= 0,CS210 = 1} // array field that provides short description for each of classes, // returns string description of the course private String[] courseDescription = {"Intermediate C#: Teaches intermediate elements of C# programming and software design", "Career Development Strategies: Teaches principles for career progression, resume preparation, and overall self anaylsis"}; // indexer that takes one of the enumerated courses as an index // and returns the String description of the course public String this[CourseName index] { get { if (index == 1) return courseDescription[0]; else return courseDescription[1]; } set { if (index == 1) courseDescription[0] = value; else courseDescription[1] = value; } } } }//end public class MyCourses I'm working on this homework project and having trouble understanding the text explaining how to correctly take the accessed value of the enumeration and then apply the string array value to it. Can you please help me understand this? The text we are using is very difficult and poorly written for a beginner to understand, so I'm kind of on my own here. I've got the first parts written, but need some help on the accessing of the enumeration value and assigning, i think i'm close, but don't understand how to properly get and set the values on this. Please do not provide me with direct code answers, unless a MSDN style explanation that is generalized and not specific to my project. ie: public class MyClass { string field1; string field2; //properties public string Value1 get etc... Thanks!

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• How to get all captures of subgroup matches with preg_match_all()?

  - by hakre

  Update/Note: I think what I'm probably looking for is to get the captures of a group in PHP. Referenced: PCRE regular expressions using named pattern subroutines. (Read carefully:) I have a string that contains a variable number of segments (simplified): $subject = 'AA BB DD '; // could be 'AA BB DD CC EE ' as well I would like now to match the segments and return them via the matches array: $pattern = '/^(([a-z]+) )+$/i'; $result = preg_match_all($pattern, $subject, $matches); This will only return the last match for the capture group 2: DD. Is there a way that I can retrieve all subpattern captures (AA, BB, DD) with one regex execution? Isn't preg_match_all suitable for this? This question is a generalization. Both the $subject and $pattern are simplified. Naturally with such the general list of AA, BB, .. is much more easy to extract with other functions (e.g. explode) or with a variation of the $pattern. But I'm specifically asking how to return all of the subgroup matches with the preg_...-family of functions. For a real life case imagine you have multiple (nested) level of a variant amount of subpattern matches. Example This is an example in pseudo code to describe a bit of the background. Imagine the following: Regular definitions of tokens: CHARS := [a-z]+ PUNCT := [.,!?] WS := [ ] $subject get's tokenized based on these. The tokenization is stored inside an array of tokens (type, offset, ...). That array is then transformed into a string, containing one character per token: CHARS -> "c" PUNCT -> "p" WS -> "s" So that it's now possible to run regular expressions based on tokens (and not character classes etc.) on the token stream string index. E.g. regex: (cs)?cp to express one or more group of chars followed by a punctuation. As I now can express self-defined tokens as regex, the next step was to build the grammar. This is only an example, this is sort of ABNF style: words = word | (word space)+ word word = CHARS+ space = WS punctuation = PUNCT If I now compile the grammar for words into a (token) regex I would like to have naturally all subgroup matches of each word. words = (CHARS+) | ( (CHARS+) WS )+ (CHARS+) # words resolved to tokens words = (c+)|((c+)s)+c+ # words resolved to regex I could code until this point. Then I ran into the problem that the sub-group matches did only contain their last match. So I have the option to either create an automata for the grammar on my own (which I would like to prevent to keep the grammar expressions generic) or to somewhat make preg_match working for me somehow so I can spare that. That's basically all. Probably now it's understandable why I simplified the question. Related: pcrepattern man page Get repeated matches with preg_match_all()

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• Problem in understanding connectSlotsByName() in pyqt???

  - by Jebagnanadas

  Hi all, I couldn't understand the connectSlotsByName() method which is predominently used by pyuic4.. As far the class is single in a PyQt file it's ok since we can use self which will be associated with a single object throughout.. But when we try to use various classes from different files the problem and the need to use connectSlotsByName() arises.. Here's what i encountered which is weird.. I created a stacked widget.. I placed my first widget on it.. It has a button called "Next ". On clicking next it hides the current widget and adds another widget which has the "click me" button.. The problem here is the click event for "click me" button in second is not captured.. It's a minimal example that i can give for my original problem.. Please help me.. This is file No.1..(which has the parent stacked widget and it's first page). On clicking next it adds the second page which has "clickme" button in file2.. from PyQt4 import QtCore, QtGui import file2 class Ui_StackedWidget(QtGui.QStackedWidget): def __init__(self,parent=None): QtGui.QStackedWidget.__init__(self,parent) self.setObjectName("self") self.resize(484, 370) self.setWindowTitle(QtGui.QApplication.translate("self", "stacked widget", None, QtGui.QApplication.UnicodeUTF8)) self.createWidget1() def createWidget1(self): self.page=QtGui.QWidget() self.page.setObjectName("widget1") self.pushButton=QtGui.QPushButton(self.page) self.pushButton.setGeometry(QtCore.QRect(150, 230, 91, 31)) self.pushButton.setText(QtGui.QApplication.translate("self", "Next >", None, QtGui.QApplication.UnicodeUTF8)) self.addWidget(self.page) QtCore.QMetaObject.connectSlotsByName(self.page) QtCore.QObject.connect(self.pushButton,QtCore.SIGNAL('clicked()'),self.showWidget2) def showWidget2(self): self.page.hide() obj=file2.widget2() obj.createWidget2(self) if __name__ == "__main__": import sys app = QtGui.QApplication(sys.argv) ui = Ui_StackedWidget() ui.show() sys.exit(app.exec_()) Here's file2 from PyQt4 import QtGui,QtCore class widget2(): def createWidget2(self,parent): self.page = QtGui.QWidget() self.page.setObjectName("page") self.parent=parent self.groupBox = QtGui.QGroupBox(self.page) self.groupBox.setGeometry(QtCore.QRect(30, 20, 421, 311)) self.groupBox.setObjectName("groupBox") self.groupBox.setTitle(QtGui.QApplication.translate("self", "TestGroupBox", None, QtGui.QApplication.UnicodeUTF8)) self.pushButton = QtGui.QPushButton(self.groupBox) self.pushButton.setGeometry(QtCore.QRect(150, 120, 92, 28)) self.pushButton.setObjectName("pushButton") self.pushButton.setText(QtGui.QApplication.translate("self", "Click Me", None, QtGui.QApplication.UnicodeUTF8)) self.parent.addWidget(self.page) self.parent.setCurrentWidget(self.page) QtCore.QMetaObject.connectSlotsByName(self.page) QtCore.QObject.connect(self.pushButton,QtCore.SIGNAL('clicked()'),self.printMessage) def printMessage(self): print("Hai") Though in both the widgets(i mean pages) QtCore.QMetaObject.connectSlotsByName(self.page) the clicked signal in second dialog isn't getting processed. Thanks in advance.. Might be a beginner question..

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• unrecognized selector sent to instance while trying to add an object to a mutable array

  - by madpoet

  I'm following the "Your Second iOS App" and I decided to play with the code to understand Objective C well... What I'm trying to do is simply adding an object to a mutable array in a class. Here are the classes: BirdSighting.h #import <Foundation/Foundation.h> @interface BirdSighting : NSObject @property (nonatomic, copy) NSString *name; @property (nonatomic, copy) NSString *location; @property (nonatomic, copy) NSDate *date; -(id) initWithName: (NSString *) name location:(NSString *) location date:(NSDate *) date; @end BirdSighting.m #import "BirdSighting.h" @implementation BirdSighting -(id) initWithName:(NSString *)name location:(NSString *)location date:(NSDate *)date { self = [super init]; if(self) { _name = name; _location = location; _date = date; return self; } return nil; } @end BirdSightingDataController.h #import <Foundation/Foundation.h> @class BirdSighting; @interface BirdSightingDataController : NSObject @property (nonatomic, copy) NSMutableArray *masterBirdSightingList; - (NSUInteger) countOfList; - (BirdSighting *) objectInListAtIndex: (NSUInteger) theIndex; - (void) addBirdSightingWithSighting: (BirdSighting *) sighting; @end BirdSightingDataController.m #import "BirdSightingDataController.h" @implementation BirdSightingDataController - (id) init { if(self = [super init]) { NSMutableArray *sightingList = [[NSMutableArray alloc] init]; self.masterBirdSightingList = sightingList; return self; } return nil; } -(NSUInteger) countOfList { return [self.masterBirdSightingList count]; } - (BirdSighting *) objectInListAtIndex: (NSUInteger) theIndex { return [self.masterBirdSightingList objectAtIndex:theIndex]; } - (void) addBirdSightingWithSighting: (BirdSighting *) sighting { [self.masterBirdSightingList addObject:sighting]; } @end And this is where I'm trying to add a BirdSighting instance to the mutable array: #import "BirdsMasterViewController.h" #import "BirdsDetailViewController.h" #import "BirdSightingDataController.h" #import "BirdSighting.h" @implementation BirdsMasterViewController - (void)awakeFromNib { [super awakeFromNib]; BirdSightingDataController *dataController = [[BirdSightingDataController alloc] init]; NSDate *date = [NSDate date]; BirdSighting *sighting = [[[BirdSighting alloc] init] initWithName:@"Ebabil" location:@"Ankara" date: date]; [dataController addBirdSightingWithSighting: sighting]; NSLog(@"dataController: %@", dataController.masterBirdSightingList); self.dataController = dataController; } .......... @end It throws NSInvalidArgumentException in BirdSightingDataController addBirdSightingWithSighting method... What am I doing wrong?

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• C++ constructor problem, values not being set

  - by 2Real

  Hi, I'm new to C++ and I'm trying to figure out this problem I'm having with my constructor for one of my classes. What happens is... all my variables are initialized properly except two (health and type). #pragma once #include <irrlicht.h> #include <vector> #include <cassert> using namespace irr; using namespace core; using namespace scene; enum { PLAYER = 0, NPC = 1, SOLDIER = 2, CHAINGUNNER = 3 }; class Model { public: Model(void); Model(int id, std::vector<ISceneNode*> modelVec, int modType); ~Model(void); std::vector<int> path; std::vector<ISceneNode*> model; int endNode; int type; int animate; int health; u32 lastAnimation; private: int mId; }; #include "Model.h" Model::Model(void) { //assert(false); } Model::Model(int id, std::vector<ISceneNode*> modelVec, int modType) { path = std::vector<int>(); model = modelVec; endNode = 0; type = modType; animate = 0; health = 100; lastAnimation = 0; mId = id; } Model::~Model(void) {} I create a model with Model soldier(id, model, SOLDIER) Everything is set properly except type and health. I've tried many different things, but I cannot figure out my problem. I'm not sure but the default constructor is being called. It doesn't make sense because I make no called to that constructor. Thanks,

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• Making a Wrapper class for ActiveMQ

  - by DarthVader

  I want to make a Wrapper class for ActiveMQ which will have only send and get functions. I want to wrap them in a static class. Users can use this client and send, get messages to the activemq instance. I want this process to be transparent. There are two classes in this link My only handicap is, i need to this in c++ and not sure where to start. I havent used c++ for ages and now not sure how I can create this wrapper class. I m giving it a try as follows: // .h file #include <stdlib.h> #include <iostream> using namespace std; class ActiveMQWrapper { public: static void send(std::string message); static std::string get(); }; // .cpp file #include<string> #include<iostream> #include "ActiveMQWrapper.h" void ActiveMQWrapper::send(std::string message){ std::cout<<message; } std::string ActiveMQWrapper::get(){ return "test"; } // test file #include <string> #include <iostream> #include "ActiveMQWrapper.h" int main() { std::string foo ="test"; ActiveMQWrapper::send(foo); std::cout<<ActiveMQWrapper::get(); return 1; } When I added the following to .h file, hell breaks loose. Do you think I should seperate this impl to a factory and initialize and instance and return to the wrapper above? How do i deal with all the dependencies? private: Connection* connection; Session* session; Destination* destination; MessageProducer* producer; int numMessages; bool useTopic; bool sessionTransacted; std::string brokerURI; and the header files, i get several messages as errors, which complains about the path. How can i get this correct? I eventually want to build a Factory, get an instance and send or get the messages to the queue. is there a code sample i can look into to get this right? essential i want to use the functionality of only this producer and consumer. Edit: I understand there is no such thing as static class in C++ . This is my reference.

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• Vector Troubles in C++

  - by DistortedLojik

  I am currently working on a project that deals with a vector of objects of a People class. The program compiles and runs just fine, but when I use the debugger it dies when trying to do anything with the PersonWrangler object. I currently have 3 different classes, one for the person, a personwrangler which handles all of the people collectively, and a game class that handles the game input and output. Edit: My basic question is to understand why it is dying when it calls outputPeople. Also I would like to understand why my program works exactly as it should unless I use the debugger. The outputPeople function works the way I intended that way. Edit 2: The callstack has 3 bad calls which are: std::vector ::begin(this=0xbaadf00d) std::vector ::size(this=0xbaadf00d) PersonWrangler::outputPeople(this=0xbaadf00d) Relevant code: class Game { public: Game(); void gameLoop(); void menu(); void setStatus(bool inputStatus); bool getStatus(); PersonWrangler* hal; private: bool status; }; which calls outputPeople where it promptly dies from a baadf00d error. void Game::menu() { hal->outputPeople(); } where hal is an object of PersonWrangler type class PersonWrangler { public: PersonWrangler(int inputStartingNum); void outputPeople(); vector<Person*> peopleVector; vector<Person*>::iterator personIterator; int totalPeople; }; and the outputPeople function is defined as void PersonWrangler::outputPeople() { int totalConnections = 0; cout << " Total People:" << peopleVector.size() << endl; for (unsigned int i = 0;i < peopleVector.size();i++) { sort(peopleVector[i]->connectionsVector.begin(),peopleVector[i]->connectionsVector.end()); peopleVector[i]->connectionsVector.erase( unique (peopleVector[i]->connectionsVector.begin(),peopleVector[i]->connectionsVector.end()),peopleVector[i]->connectionsVector.end()); peopleVector[i]->outputPerson(); totalConnections+=peopleVector[i]->connectionsVector.size(); } cout << "Total connections:" << totalConnections/2 << endl; }

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• How to auto-generate early bound properties for Entity specific (ie Local) Option Set text values?

  - by Daryl

  After spending a year working with the Microsoft.Xrm.Sdk namespace, I just discovered yesterday the Entity.FormattedValues property contains the text value for Entity specific (ie Local) Option Set texts. The reason I didn't discover it before, is there is no early bound method of getting the value. i.e. entity.new_myOptionSet is of type OptionSetValue which only contains the int value. You have to call entity.FormattedValues["new_myoptionset"] to get the string text value of the OptionSetValue. Therefore, I'd like to get the crmsrvcutil to auto-generate a text property for local option sets. i.e. Along with Entity.new_myOptionSet being generated as it currently does, Entity.new_myOptionSetText would be generated as well. I've looked into the Microsoft.Crm.Services.Utility.ICodeGenerationService, but that looks like it is mostly for specifying what CodeGenerationType something should be... Is there a way supported way using CrmServiceUtil to add these properties, or am I better off writing a custom app that I can run that can generate these properties as a partial class to the auto-generated ones? Edit - Example of the code that I would like to be generated Currently, whenever I need to access the text value of a OptionSetValue, I use this code: var textValue = OptionSetCache.GetText(service, entity, e => e.New_MyOptionSet); The option set cache will use the entity.LogicalName, and the property expression to determine the name of the option set that I'm asking for. It will then query the SDK using the RetrieveAttriubteRequest, to get a list of the option set int and text values, which it then caches so it doesn't have to hit CRM again. It then looks up the int value of the New_MyOptionSet of the entity and cross references it with the cached list, to get the text value of the OptionSet. Instead of doing all of that, I can just do this (assuming that the entity has been retrieved from the server, and not just populated client side): var textValue = entity.FormattedValues["new_myoptionset"]; but the "new_myoptionset" is no longer early bound. I would like the early bound entity classes that gets generated to also generate an extra "Text" property for OptionSetValue properties that calls the above line, so my entity would have this added to it: public string New_MyOptionSetText { return this.GetFormattedAttributeValue("new_myoptionset"); // this is a protected method on the Entity class itself... }

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• factory class, wrong number of arguments being passed to subclass constructor

  - by Hugh Bothwell

  I was looking at Python: Exception in the separated module works wrong which uses a multi-purpose GnuLibError class to 'stand in' for a variety of different errors. Each sub-error has its own ID number and error format string. I figured it would be better written as a hierarchy of Exception classes, and set out to do so: class GNULibError(Exception): sub_exceptions = 0 # patched with dict of subclasses once subclasses are created err_num = 0 err_format = None def __new__(cls, *args): print("new {}".format(cls)) # DEBUG if len(args) and args[0] in GNULibError.sub_exceptions: print(" factory -> {} {}".format(GNULibError.sub_exceptions[args[0]], args[1:])) # DEBUG return super(GNULibError, cls).__new__(GNULibError.sub_exceptions[args[0]], *(args[1:])) else: print(" plain {} {}".format(cls, args)) # DEBUG return super(GNULibError, cls).__new__(cls, *args) def __init__(self, *args): cls = type(self) print("init {} {}".format(cls, args)) # DEBUG self.args = args if cls.err_format is None: self.message = str(args) else: self.message = "[GNU Error {}] ".format(cls.err_num) + cls.err_format.format(*args) def __str__(self): return self.message def __repr__(self): return '{}{}'.format(type(self).__name__, self.args) class GNULibError_Directory(GNULibError): err_num = 1 err_format = "destination directory does not exist: {}" class GNULibError_Config(GNULibError): err_num = 2 err_format = "configure file does not exist: {}" class GNULibError_Module(GNULibError): err_num = 3 err_format = "selected module does not exist: {}" class GNULibError_Cache(GNULibError): err_num = 4 err_format = "{} is expected to contain gl_M4_BASE({})" class GNULibError_Sourcebase(GNULibError): err_num = 5 err_format = "missing sourcebase argument: {}" class GNULibError_Docbase(GNULibError): err_num = 6 err_format = "missing docbase argument: {}" class GNULibError_Testbase(GNULibError): err_num = 7 err_format = "missing testsbase argument: {}" class GNULibError_Libname(GNULibError): err_num = 8 err_format = "missing libname argument: {}" # patch master class with subclass reference # (TO DO: auto-detect all available subclasses instead of hardcoding them) GNULibError.sub_exceptions = { 1: GNULibError_Directory, 2: GNULibError_Config, 3: GNULibError_Module, 4: GNULibError_Cache, 5: GNULibError_Sourcebase, 6: GNULibError_Docbase, 7: GNULibError_Testbase, 8: GNULibError_Libname } This starts out with GNULibError as a factory class - if you call it with an error number belonging to a recognized subclass, it returns an object belonging to that subclass, otherwise it returns itself as a default error type. Based on this code, the following should be exactly equivalent (but aren't): e = GNULibError(3, 'missing.lib') f = GNULibError_Module('missing.lib') print e # -> '[GNU Error 3] selected module does not exist: 3' print f # -> '[GNU Error 3] selected module does not exist: missing.lib' I added some strategic print statements, and the error seems to be in GNULibError.__new__: >>> e = GNULibError(3, 'missing.lib') new <class '__main__.GNULibError'> factory -> <class '__main__.GNULibError_Module'> ('missing.lib',) # good... init <class '__main__.GNULibError_Module'> (3, 'missing.lib') # NO! ^ why? I call the subclass constructor as subclass.__new__(*args[1:]) - this should drop the 3, the subclass type ID - and yet its __init__ is still getting the 3 anyway! How can I trim the argument list that gets passed to subclass.__init__?

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• How can I map a String to a function in Java?

  - by Bears will eat you

  Currently, I have a bunch of Java classes that implement a Processor interface, meaning they all have a processRequest(String key) method. The idea is that each class has a few (say, <10) member Strings, and each of those maps to a method in that class via the processRequest method, like so: class FooProcessor implements Processor { String key1 = "abc"; String key2 = "def"; String key3 = "ghi"; // and so on... String processRequest(String key) { String toReturn = null; if (key1.equals(key)) toReturn = method1(); else if (key2.equals(key)) toReturn = method2(); else if (key3.equals(key)) toReturn = method3(); // and so on... return toReturn; } String method1() { // do stuff } String method2() { // do other stuff } String method3() { // do other other stuff } // and so on... } You get the idea. This was working fine for me, but now I need a runtime-accessible mapping from key to function; not every function actually returns a String (some return void) and I need to dynamically access the return type (using reflection) of each function in each class that there's a key for. I already have a manager that knows about all the keys, but not the mapping from key to function. My first instinct was to replace this mapping using if-else statements with a Map<String, Function>, like I could do in Javascript. But, Java doesn't support first-class functions so I'm out of luck there. I could probably dig up a third-party library that lets me work with first-class functions, but I haven't seen any yet, and I doubt that I need an entire new library. I also thought of putting these String keys into an array and using reflection to invoke the methods by name, but I see two downsides to this method: My keys would have to be named the same as the method - or be named in a particular, consistent way so that it's easy to map them to the method name. This seems WAY slower than the if-else statements I have right now. Efficiency is something of a concern because these methods will tend to get called pretty frequently, and I want to minimize unnecessary overhead. TL; DR: I'm looking for a clean, minimal-overhead way to map a String to some sort of a Function object that I can invoke and call (something like) getReturnType() on. I don't especially mind using a 3rd-party library if it really fits my needs. I also don't mind using reflection, though I would strongly prefer to avoid using reflection every single time I do a method lookup - maybe using some caching strategy that combines the Map with reflection. Thoughts on a good way to get what I want? Cheers!

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• What should I learn & use to become a pro in PHP & Python Web development?

  - by pecker

  Hello, I'll just show some code to show how I do web development in PHP. <html> <head> <title>Example #3 TDavid's Very First PHP Script ever!</title> </head> <? print(Date("m/j/y")); require_once("somefile.php"); $mysql_db = "DATABASE NAME"; $mysql_user = "YOUR MYSQL USERNAME"; $mysql_pass = "YOUR MYSQL PASSWORD"; $mysql_link = mysql_connect("localhost", $mysql_user, $mysql_pass); mysql_select_db($mysql_db, $mysql_link); $result = mysql_query("SELECT impressions from tds_counter where COUNT_ID='$cid'", $mysql_link); if(mysql_num_rows($result)) { mysql_query("UPDATE tds_counter set impressions=impressions+1 where COUNT_ID='$cid'", $mysql_link); $row = mysql_fetch_row($result); if(!$inv) { print("$row[0]"); } } ?> <body> </body> </html> Thats it. I write every file like this. Recently, I learnt OOP and started using classes & objects in PHP. I hear that there are many frameworks there for PHP. They say that one must use these libraries. But I feel they are just making things complicated. Anyway, this is how I've been doing my web development. Now, I want to improve this. and make it professional. Also I want to move to Python. I searched SO archives and found everyone suggesting Django. But, can any one give me some idea about how web development in Python works? user (client) request for page --- webserver(-embedded PHP interpreter) ---- Server side(PHP) Script --- MySQL Server. Now, is it that instead of PHP interpreter there is python interpreter & instead of php script there is python script, which contains both HTML & python (embedded in some kind of python tags). Python script connects to database server and fetches some data which will be printed as HTML. or is it different in python world? Is this Django thing like frameworks for PHP? Can't one code in python without using Django. Because, I never encountered any post without django Please give me some kick start.

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• Pass Variables In Inheritance (Obj - C)

  - by Marmik Shah

  I working on a project in Obj-C where i have a base class (ViewController) and a Derived Class (MultiPlayer). Now i have declared certain variables and properties in the base class. My properties are getting accessed from the derived class but im not able to access the variables (int,char and bool type). I'm completely new to Obj-C so i have no clue whats wrong. I have used the data types which are used in C and C++. Is there some specific way to declare variables in Obj-C?? If so, How? Here are my files ViewController.h #import <UIKit/UIKit.h> @interface ViewController : UIViewController @property (weak,nonatomic) IBOutlet UIImageView* backGroungImage; @property (strong,nonatomic) IBOutlet UIImageView *blockView1; @property (strong,nonatomic) IBOutlet UIImageView *blockView2; @property (strong,nonatomic) IBOutlet UIImageView *blockView3; @property (strong,nonatomic) IBOutlet UIImageView *blockView4; @property (strong,nonatomic) IBOutlet UIImageView *blockView5; @property (strong,nonatomic) IBOutlet UIImageView *blockView6; @property (strong,nonatomic) IBOutlet UIImageView *blockView7; @property (strong,nonatomic) IBOutlet UIImageView *blockView8; @property (strong,nonatomic) IBOutlet UIImageView *blockView9; @property (strong,nonatomic) UIImage *x; @property (strong,nonatomic) UIImage *O; @property (strong,nonatomic) IBOutlet UIImageView* back1; @property (strong,nonatomic) IBOutlet UIImageView* back2; @end ViewController.m #import "ViewController.h" @interface ViewController () @end @implementation ViewController int chooseTheBackground = 0; int movesToDecideXorO = 0; int winningArrayX[3]; int winningArrayO[3]; int blocksTotal[9] = {8,3,4,1,5,9,6,7,2}; int checkIfContentInBlocks[9] = {0,0,0,0,0,0,0,0,0}; char determineContentInBlocks[9] = {' ',' ',' ',' ',' ',' ',' ',' ',' '}; bool player1Win = false; bool player2Win = false; bool playerWin = false; bool computerWin = false; - (void)viewDidLoad { [super viewDidLoad]; if(chooseTheBackground==0) { UIImage* backImage = [UIImage imageNamed:@"MainBack1.png"]; _backGroungImage.image=backImage; } if(chooseTheBackground==1) { UIImage* backImage = [UIImage imageNamed:@"MainBack2.png"]; _backGroungImage.image=backImage; } } - (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated. } @end I am not able to use the above declared variables in my derived classes!

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• Starting jetty with spring xml as a background process/thread

  - by compass

  My goal is to set up a jetty test server and inject a custom servlet to test some REST classes in my project. I was able to launch the server with spring xml and run tests against that server. The issue I'm having is sometimes after the server started, the process stopped at the point before running the tests. It seems jetty didn't go to background. It works every time on my computer. But when I deployed to my CI server, it doesn't work. It also doesn't work when I'm on VPN. (Strange.) The server should be completed initialized as when the tests stuck, I was able to access the server using a browser. Here is my spring context xml: .... <bean id="servletHolder" class="org.eclipse.jetty.servlet.ServletHolder"> <constructor-arg ref="courseApiServlet"/> </bean> <bean id="servletHandler" class="org.eclipse.jetty.servlet.ServletContextHandler"/> <!-- Adding the servlet holders to the handlers --> <bean id="servletHandlerSetter" class="org.springframework.beans.factory.config.MethodInvokingFactoryBean"> <property name="targetObject" ref="servletHandler"/> <property name="targetMethod" value="addServlet"/> <property name="arguments"> <list> <ref bean="servletHolder"/> <value>/*</value> </list> </property> </bean> <bean id="httpTestServer" class="org.eclipse.jetty.server.Server" init-method="start" destroy-method="stop" depends-on="servletHandlerSetter"> <property name="connectors"> <list> <bean class="org.eclipse.jetty.server.nio.SelectChannelConnector"> <property name="port" value="#{settings['webservice.server.port']}" /> </bean> </list> </property> <property name="handler"> <ref bean="servletHandler" /> </property> </bean> Running latest Jetty 8.1.8 server and Spring 3.1.3. Any idea?

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• Adding Related Entities without using navigation properties

  - by Barisa Puter

  I have the following classes, set for testing: public class Company { [DatabaseGenerated(DatabaseGeneratedOption.Identity)] public int Id { get; set; } public string Name { get; set; } } public class Employee { [DatabaseGenerated(DatabaseGeneratedOption.Identity)] public int Id { get; set; } public string Name { get; set; } public int CompanyId { get; set; } public virtual Company Company { get; set; } } public class EFTestDbContext : DbContext { public DbSet<Employee> Employees { get; set; } public DbSet<Company> Companies { get; set; } } For the sake of testing, I wanted to insert one company and one employee for that company with single SaveChanges call, like this: Company company = new Company { Name = "Sample company" }; context.Companies.Add(company); // ** UNCOMMENTED FOR TEST 2 //Company company2 = new Company //{ // Name = "Some other company" //}; //context.Companies.Add(company2); Employee employee = new Employee { Name = "Hans", CompanyId = company.Id }; context.Employees.Add(employee); context.SaveChanges(); Even though I am not using navigational properties, but instead I've made relation over Id, this somehow mysteriously worked - employee was saved with proper foreign key to company which got updated from 0 to real value, which made me go ?!?! Some hidden C# feature? Then I've decided to add more code, which is commented in the snippet above, making it to be inserting of 2 x Company entity and 1 x Employee entity, and then I got exception: Unable to determine the principal end of the 'CodeLab.EFTest.Employee_Company' relationship. Multiple added entities may have the same primary key. Does this mean that in cases where foreign key is 0, and there is a single matching entity being inserted in same SaveChanges transaction, Entity Framework will assume that foreign key should be for that matching entity? In second test, when there are two entities matching the relation type, Entity Framework throws an exception as it is not able to figure out to which of the Companies Employee should be related to.

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• best alternative to in-definition initialization of static class members? (for SVN keywords)

  - by Jeff

  I'm storing expanded SVN keyword literals for .cpp files in 'static char const *const' class members and want to store the .h descriptions as similarly as possible. In short, I need to guarantee single instantiation of a static member (presumably in a .cpp file) to an auto-generated non-integer literal living in a potentially shared .h file. Unfortunately the language makes no attempt to resolve multiple instantiations resulting from assignments made outside class definitions and explicitly forbids non-integer inits inside class definitions. My best attempt (using static-wrapping internal classes) is not too dirty, but I'd really like to do better. Does anyone have a way to template the wrapper below or have an altogether superior approach? // Foo.h: class with .h/.cpp SVN info stored and logged statically class Foo { static Logger const verLog; struct hInfoWrap; public: static hInfoWrap const hInfo; static char const *const cInfo; }; // Would like to eliminate this per-class boilerplate. struct Foo::hInfoWrap { hInfoWrapper() : text("$Id$") { } char const *const text; }; ... // Foo.cpp: static inits called here Foo::hInfoWrap const Foo::hInfo; char const *const Foo::cInfo = "$Id$"; Logger const Foo::verLog(Foo::cInfo, Foo::hInfo.text); ... // Helper.h: output on construction, with no subsequent activity or stored fields class Logger { Logger(char const *info1, char const *info2) { cout << info0 << endl << info1 << endl; } }; Is there a way to get around the static linkage address issue for templating the hInfoWrap class on string literals? Extern char pointers assigned outside class definitions are linguistically valid but fail in essentially the same manner as direct member initializations. I get why the language shirks the whole resolution issue, but it'd be very convenient if an inverted extern member qualifier were provided, where the definition code was visible in class definitions to any caller but only actually invoked at the point of a single special declaration elsewhere. Anyway, I digress. What's the best solution for the language we've got, template or otherwise? Thanks!

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• Have main thread wait for a boost thread complete a task (but not finish).

  - by JAKE6459

  I have found plenty on making one thread wait for another to finish executing before continuing, but that is not what I wanted to do. I am not very familiar with using any multi-threading apis but right now I'm trying to learn boost. My situation is that I am using my main thread (the starting one from int main()) to create an instance of a class that is in charge of interacting with the main GUI. A class function is then called that creates a boost thread which in turn creates the GUI and runs the message pump. The thing I want to do is when my main thread calls the classes member function to create the GUI, I don't want that function to return until I tell it to from the newly created thread. This way my main thread can't continue and call more functions from the GUI class that interact with the GUI thread until that thread has completed GUI creation and entered the message loop. I think I may be able to figure it out if it was multiple boost thread objects interacting with each other, but when it is the main thread (non-boost object) interacting with a boost thread object, I get lost. Eventually I want a loop in my main thread to call a class function (among other tasks) to check if the user as entered any new input into the GUI (buy any changes detected by the message loop being updated into a struct and changing a bool to tell the main thread in the class function a change has occurred). Any suggestions for any of this would be greatly appreciated. This is the member function called by the main thread. int ANNGUI::CreateGUI() { GUIMain = new Main(); GUIThread = new boost::thread(boost::bind(&Main::MainThreadFunc, GUIMain)); return 0; }; This is the boost thread starting function. void Main::MainThreadFunc() { ANNVariables = new GUIVariables; WndProc = new WindowProcedure; ANNWindowsClass = new WindowsClass(ANNVariables, WndProc); ANNWindow = new MainWindow(ANNVariables); GUIMessagePump = new MessagePump; ANNWindow-ShowWindows(); while(true) { GUIMessagePump-ProcessMessage(); } }; BTW, everything compiles fine and when I run it, it works I just put a sleep() in the main thread so I can play with the GUI a little.

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• Need help with map (c++, STL)

  - by Mike Dooley

  Hi folks! Actually I'm new to C++. I tried something out (actually the map container) but it doesn't work the way I assumed it will... Before posting my code, I will explain it shortly. I created 3 classes: ClassA ClassDerivedA ClassAnotherDerivedA The two last ones are derived from "ClassA". Further I created a map: map<string,ClassA> test_map; I put some objects (from Type ClassDerivedA and ClassAnotherDerivedA) into the map. Keep in mind: the mapped value is from type "ClassA". This will only work because of Polymorphism. Finally I created an iterator which runs over my map and compares the user input with my keys in the map. If they match, it will call a specific method called "printOutput". And there is the Problem: Although i declared "printOutput" as "virtual" the only method called is the one from my base class, but why? and here is the code: #include <iostream> #include <map> using namespace std; class ClassA { public: virtual void printOutput() { cout << "ClassA" << endl; } }; class ClassDerivedA : public ClassA { public: void printOutput() { cout << "ClassDerivedA" << endl; } }; class ClassAnotherDerivedA: public ClassA { public: void printOutput() { cout << "ClassAnotherDerivedA" << endl; } }; int main() { ClassDerivedA class_derived_a; ClassAnotherDerivedA class_another_a; map<string,ClassA> test_map; test_map.insert(pair<string,ClassA>("deriveda", class_derived_a)); test_map.insert(pair<string,ClassA>("anothera", class_another_a)); string s; while( cin >> s ) { if( s != "quit" ) { map<string,ClassA>::iterator it = test_map.find(s); if(it != test_map.end()) it->second.printOutput(); } else break; } } Blockquote

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• Manipulating values from database table with php

  - by charliecodex23

  I currently have 5 tables in MySQL database. Some of them share foreign keys and are interdependent of each other. I am displaying classes accordingly to their majors. Each class is taught during the fall, spring or all_year. In my database I have a table named semester which has an id, year, and semester fields. The semester field in particular is a tinyint that has three values 0, 1, 2. This signifies the fall, spring or all_year. When I display the query instead of having it show 0 or 1 or 2 can I have it show fall, spring etc? Extra: How can I add space to the end of each loop so the data doesn't look clustered? Key 0 Fall 1 Spring 2 All-year PHP <? try { $pdo = new PDO ("mysql:host=$hostname;dbname=$dbname","$username","$pw"); } catch (PDOException $e) { echo "Failed to get DB handle: " . $e->getMessage() . "\n"; exit; } $query = $pdo->prepare("SELECT course.name, course.code, course.description, course.hours, semester.semester, semester.year FROM course LEFT JOIN major_course_xref ON course.id = major_course_xref.course_id LEFT JOIN major ON major.id = major_course_xref.major_id LEFT JOIN course_semester_xref ON course.id = course_semester_xref.course_id LEFT JOIN semester ON course_semester_xref.semester_id = semester.id"); $query->execute(); if ($query->execute()){ while ($row = $query->fetch(PDO::FETCH_ASSOC)){ print $row['name'] . "<br>"; print $row['code'] . "<br>"; print $row['description'] . "<br>"; print $row['hours'] . " hrs.<br>"; print $row['semester'] . "<br>"; print $row['year'] . "<br>"; } } else echo 'Could not fetch results.'; unset($pdo); unset($query); ?> Current Display Computer Programming I CPSC1400 Introduction to disciplined, object-oriented program development. 4 hrs. 0 2013 Desire Display Computer Programming I CPSC1400 Introduction to disciplined, object-oriented program development. 4 hrs. Fall 2013

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• Abstract class and an inheritor: is it possible to factorize .parent() here?

  - by fge

  Here are what I think are the relevant parts of the code of these two classes. First, TreePointer (original source here): public abstract class TreePointer<T extends TreeNode> implements Iterable<TokenResolver<T>> { //... /** * What this tree can see as a missing node (may be {@code null}) */ private final T missing; /** * The list of token resolvers */ protected final List<TokenResolver<T>> tokenResolvers; /** * Main protected constructor * * <p>This constructor makes an immutable copy of the list it receives as * an argument.</p> * * @param missing the representation of a missing node (may be null) * @param tokenResolvers the list of reference token resolvers */ protected TreePointer(final T missing, final List<TokenResolver<T>> tokenResolvers) { this.missing = missing; this.tokenResolvers = ImmutableList.copyOf(tokenResolvers); } /** * Alternate constructor * * <p>This is the same as calling {@link #TreePointer(TreeNode, List)} with * {@code null} as the missing node.</p> * * @param tokenResolvers the list of token resolvers */ protected TreePointer(final List<TokenResolver<T>> tokenResolvers) { this(null, tokenResolvers); } //... /** * Tell whether this pointer is empty * * @return true if the reference token list is empty */ public final boolean isEmpty() { return tokenResolvers.isEmpty(); } @Override public final Iterator<TokenResolver<T>> iterator() { return tokenResolvers.iterator(); } // .equals(), .hashCode(), .toString() follow } Then, JsonPointer, which contains this .parent() method which I'd like to factorize here (original source here: public final class JsonPointer extends TreePointer<JsonNode> { /** * The empty JSON Pointer */ private static final JsonPointer EMPTY = new JsonPointer(ImmutableList.<TokenResolver<JsonNode>>of()); /** * Return an empty JSON Pointer * * @return an empty, statically allocated JSON Pointer */ public static JsonPointer empty() { return EMPTY; } //... /** * Return the immediate parent of this JSON Pointer * * <p>The parent of the empty pointer is itself.</p> * * @return a new JSON Pointer representing the parent of the current one */ public JsonPointer parent() { final int size = tokenResolvers.size(); return size <= 1 ? EMPTY : new JsonPointer(tokenResolvers.subList(0, size - 1)); } // ... } As mentioned in the subject, the problem I have here is with JsonPointer's .parent() method. In fact, the logic behind this method applies to TreeNode all the same, and therefore to its future implementations. Except that I have to use a constructor, and of course such a constructor is implementation dependent :/ Is there a way to make that .parent() method available to each and every implementation of TreeNode or is it just a pipe dream?

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• Terminating a long-executing thread and then starting a new one in response to user changing parameters via UI in an applet

  - by user1817170

  I have an applet which creates music using the JFugue API and plays it for the user. It allows the user to input a music phrase which the piece will be based on, or lets them choose to have a phrase generated randomly. I had been using the following method (successfully) to simply stop and start the music, which runs in a thread using the Player class from JFugue. I generate the music using my classes and user input from the applet GUI...then... private playerThread pthread; private Thread threadPlyr; private Player player; (from variables declaration) public void startMusic(Pattern p) // pattern is a JFugue object which holds the generated music { if (pthread == null) { pthread = new playerThread(); } else { pthread = null; pthread = new playerThread(); } if (threadPlyr == null) { threadPlyr = new Thread(pthread); } else { threadPlyr = null; threadPlyr = new Thread(pthread); } pthread.setPattern(p); threadPlyr.start(); } class playerThread implements Runnable // plays midi using jfugue Player { private Pattern pt; public void setPattern(Pattern p) { pt = p; } @Override public void run() { try { player.play(pt); // takes a couple mins or more to execute resetGUI(); } catch (Exception exception) { } } } And the following to stop music when user presses the stop/start button while Player.isPlaying() is true: public void stopMusic() { threadPlyr.interrupt(); threadPlyr = null; pthread = null; player.stop(); } Now I want to implement a feature which will allow the user to change parameters while the music is playing, create an updated music pattern, and then play THAT pattern. Basically, the idea is to make it simulate "real time" adjustments to the generated music for the user. Well, I have been beating my head against the wall on this for a couple of weeks. I've read all the standard java documentation, researched, read, and searched forums, and I have tried many different ideas, none of which have succeeded. The problem I've run into with all approaches I've tried is that when I start the new thread with the new, updated musical pattern, all the old threads ALSO start, and there is a cacophony of unintelligible noise instead of my desired output. From what I've gathered, the issue seems to be that all the methods I've come across require that the thread is able to periodically check the value of a "flag" variable and then shut itself down from within its "run" block in response to that variable. However, since my thread makes a call that takes several minutes minimum to execute (playing the music), and I need to terminate it WHILE it is executing this, there is really no safe way to do so. So, I'm wondering if there is something I'm missing when it comes to threads, or if perhaps I can accomplish my goal using a totally different approach. Any ideas or guidance is greatly appreciated! Thank you!

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