Search Results

Search found 1806 results on 73 pages for 'lazy evaluation'.

Page 21/73 | < Previous Page | 17 18 19 20 21 22 23 24 25 26 27 28  | Next Page >

  • Not loading associations without proxies in NHibernate

    - by Alice
    I don't like the idea of proxy and lazy loading. I don't need that. I want pure POCO. And I want to control loading associations explicitly when I need. Here is entity public class Post { public long Id { get; set; } public long OwnerId { get; set; } public string Content { get; set; } public User Owner { get; set; } } and mapping <class name="Post"> <id name="Id" /> <property name="OwnerId" /> <property name="Content" /> <many-to-one name="Owner" column="OwnerId" /> </class> However if I specify lazy="false" in the mapping, Owner is always eagerly fetched. I can't remove many-to-one mapping because that also disables explicit loading or a query like from x in session.Query<Comment>() where x.Owner.Title == "hello" select x; I specified lazy="true" and set use_proxy_validator property to false. But that also eager loads Owner. Is there any way to load only Post entity?

    Read the article

  • Question About Fk refrence in The Collection

    - by Ahmed
    Hi , i have 2 entities : ( person ) & (Address) with follwing mapping : <class name="Adress" table="Adress" lazy="false"> <id name="Id" column="Id"> <generator class="native" /> </id> <many-to-one name="Person" class="Person"> <column name="PersonId" /> </many-to-one> </class> <class name="Person" table="Person" lazy="false"> <id name="PersonId" column="PersonId"> <generator class="native" /> </id> <property name="Name" column="Name" type="String" not-null="true" /> <set name="Adresses" lazy="true" inverse="true" cascade="save-update"> <key> <column name="PersonId" /> </key> <one-to-many class="Adress" /> </set> </class> my propblem is that when i set Adrees.Person with new object of person ,The collection person.Adresses doesn't update itself . should i update every end role of the association to be updated in the two both? another thing : if i updated the Fk manually like this : Adress.PersonId it doesn't break or change association. does this is Nhibernte behavior ? thanks in advance , i am waiting for your experiencies

    Read the article

  • I need help solving a rather weird error in a WCF service.

    - by Moulde
    Hi.. I have a solution that contains three projects. A main project with my MVC app, a silverlight application and a (silverlight enabled) WCF service project. In my silverlight project i have made a Service Reference to my WCF service. And i pretty much got that working. In my WCF service i have a method that returns an Book object, which got some random fields like title, date etc. In the book class, i have a ICollection field that contains a list of events. The book class is generated using entity framework 4.0, and Lazy Loading is enabled. If i in my getBook(int id) method return a book with the events field not initialized, it works as a charm. But if i initialize the field, i'm getting this error. The server did not provide a meaningful reply; this might be caused by a contract mismatch, a premature session shutdown or an internal server error. I have a few ideas why that is happening, and while writing this i just got another one. The wcf service somehow threw away the reference to the event class. That would be very weird since i have a reference between my main mvc app (with the models) and my WCF service. Since i have enabled lazy loading in EF 4.0, i suspect that it may be the thing generating the error. But i'm not sure why that would be, because i'm not in any way accessing that field. I could understand that i may not be able to access the events field after i recive the object in my silverlight application since the connection between the book object and the entity framework is like broken. Did i mention that Lazy Loading is enabled on my EF instance? And there is no inner exception in the thrown exception. Thanks in advance. Malte Baden Hansen

    Read the article

  • Playframework sends 2 queries for fetched query

    - by MRu
    I currently have problems with the JPA at the play framework 1.2.4. I need to have a UserOptions model in a separate database and want to join it lazyly cause its only needed in one query. In this query I want to load the options eagerly and by searching I found out that can only be done by using a join query. If I use eager instead oder lazy, everything would be fine by using User.findById() and the options and the user is found in one query. But play sends two queries when I use a 'left join fetch' query. So heres the query: User.find(" SELECT user FROM User user LEFT JOIN FETCH user.options options WHERE user.id = ? ", Long.parseLong(id)).first(); And here the models: @Entity public class User extends Model { @OneToOne(mappedBy = "user", fetch = FetchType.LAZY) public UserOptions options; // ... } @Entity public class UserOptions extends Model { @OneToOne(fetch = FetchType.LAZY) public User user; } The question is why play sends two query for the fetch query? Thanks in advance

    Read the article

  • Under what circumstances will an entity be able to lazily load its relationships in JPA

    - by Mowgli
    Assuming a Java EE container is being used with JPA persistence and JTA transaction management where EJB and WAR packages are inside a EAR package. Say an entity with lazy-load relationships has just been returned from a JPQL search, such as the getBoats method below: @Stateless public class BoatFacade implements BoatFacadeRemote, BoatFacadeLocal { @PersistenceContext(unitName = "boats") private EntityManager em; @Override public List<Boat> getBoats(Collection<Integer> boatIDs) { if(boatIDs.isEmpty()) { return Collections.<Boat>emptyList(); } Query query = em.createNamedQuery("getAllBoats"); query.setParameter("boatID", boatIDs); List<Boat> boats = query.getResultList(); return boats; } } The entity: @Entity @NamedQuery( name="getAllBoats", query="Select b from Boat b where b.id in : boatID") public class Boat { @Id private long id; @OneToOne(fetch=FetchType.LAZY) private Gun mainGun; public Gun getMainGun() { return mainGun; } } Where will its lazy-load relationships be loadable (assuming the same stateless request): Same JAR: A method in the same EJB A method in another EJB A method in a POJO in the same EJB JAR Same EAR, but outside EJB JAR: A method in a web tier managed bean. A method in a web tier POJO. Different EAR: A method in a different EAR which receives the entity through RMI. What is it that restricts the scope, for example: the JPA transaction, persistence context or JTA transaction?

    Read the article

  • Hibernate Performance Best Practice?

    - by user829237
    Im writing a Web application using Hibernate 3. So, after a while i noticed that something was slow. So i tested hibernate profiler and found that hibernate will make unreasonably many db-calls for simple operation. The reason is ofcourse that i load an Object (this object has several "parents") and these "parents" have other "parents". So basicly hibernate loads them all, even though i just need the basic object. Ok, so i looked into lazy-loading. Which lead me into the Lazyloading-exception, because i have a MVC webapp. So now i'm a bit confused as to what is my best approach to this. Basicly all I need is to update a single field on an object. I already have the object-key. Should I: 1. Dig into Lazy-loading. And then rewrite my app for a open-session-view? 2. Dig into lazy-loading. And then rewrite my dao's to be more specific. E.g. writing DAO-methods that will return objects instanciated with only whats necessary for each use-case? Could be a lot of extra methods... 3. Scratch hibernate and do it myself? 4. Cant really think of other solutions right now. Any suggestions? What is the best practice?

    Read the article

  • F# for the C# Programmer

    - by mbcrump
    Are you a C# Programmer and can’t make it past a day without seeing or hearing someone mention F#?  Today, I’m going to walk you through your first F# application and give you a brief introduction to the language. Sit back this will only take about 20 minutes. Introduction Microsoft's F# programming language is a functional language for the .NET framework that was originally developed at Microsoft Research Cambridge by Don Syme. In October 2007, the senior vice president of the developer division at Microsoft announced that F# was being officially productized to become a fully supported .NET language and professional developers were hired to create a team of around ten people to build the product version. In September 2008, Microsoft released the first Community Technology Preview (CTP), an official beta release, of the F# distribution . In December 2008, Microsoft announced that the success of this CTP had encouraged them to escalate F# and it is now will now be shipped as one of the core languages in Visual Studio 2010 , alongside C++, C# 4.0 and VB. The F# programming language incorporates many state-of-the-art features from programming language research and ossifies them in an industrial strength implementation that promises to revolutionize interactive, parallel and concurrent programming. Advantages of F# F# is the world's first language to combine all of the following features: Type inference: types are inferred by the compiler and generic definitions are created automatically. Algebraic data types: a succinct way to represent trees. Pattern matching: a comprehensible and efficient way to dissect data structures. Active patterns: pattern matching over foreign data structures. Interactive sessions: as easy to use as Python and Mathematica. High performance JIT compilation to native code: as fast as C#. Rich data structures: lists and arrays built into the language with syntactic support. Functional programming: first-class functions and tail calls. Expressive static type system: finds bugs during compilation and provides machine-verified documentation. Sequence expressions: interrogate huge data sets efficiently. Asynchronous workflows: syntactic support for monadic style concurrent programming with cancellations. Industrial-strength IDE support: multithreaded debugging, and graphical throwback of inferred types and documentation. Commerce friendly design and a viable commercial market. Lets try a short program in C# then F# to understand the differences. Using C#: Create a variable and output the value to the console window: Sample Program. using System;   namespace ConsoleApplication9 {     class Program     {         static void Main(string[] args)         {             var a = 2;             Console.WriteLine(a);             Console.ReadLine();         }     } } A breeze right? 14 Lines of code. We could have condensed it a bit by removing the “using” statment and tossing the namespace. But this is the typical C# program. Using F#: Create a variable and output the value to the console window: To start, open Visual Studio 2010 or Visual Studio 2008. Note: If using VS2008, then please download the SDK first before getting started. If you are using VS2010 then you are already setup and ready to go. So, click File-> New Project –> Other Languages –> Visual F# –> Windows –> F# Application. You will get the screen below. Go ahead and enter a name and click OK. Now, you will notice that the Solution Explorer contains the following: Double click the Program.fs and enter the following information. Hit F5 and it should run successfully. Sample Program. open System let a = 2        Console.WriteLine a As Shown below: Hmm, what? F# did the same thing in 3 lines of code. Show me the interactive evaluation that I keep hearing about. The F# development environment for Visual Studio 2010 provides two different modes of execution for F# code: Batch compilation to a .NET executable or DLL. (This was accomplished above). Interactive evaluation. (Demo is below) The interactive session provides a > prompt, requires a double semicolon ;; identifier at the end of a code snippet to force evaluation, and returns the names (if any) and types of resulting definitions and values. To access the F# prompt, in VS2010 Goto View –> Other Window then F# Interactive. Once you have the interactive window type in the following expression: 2+3;; as shown in the screenshot below: I hope this guide helps you get started with the language, please check out the following books for further information. F# Books for further reading   Foundations of F# Author: Robert Pickering An introduction to functional programming with F#. Including many samples, this book walks through the features of the F# language and libraries, and covers many of the .NET Framework features which can be leveraged with F#.       Functional Programming for the Real World: With Examples in F# and C# Authors: Tomas Petricek and Jon Skeet An introduction to functional programming for existing C# developers written by Tomas Petricek and Jon Skeet. This book explains the core principles using both C# and F#, shows how to use functional ideas when designing .NET applications and presents practical examples such as design of domain specific language, development of multi-core applications and programming of reactive applications.

    Read the article

  • JavaOne 2011: Content review process and Tips for submissions

    - by arungupta
    The Technical Sessions, Birds of Feather, Panels, and Hands-on labs (basically all the content delivered at JavaOne) forms the backbone of the conference. At this year's JavaOne conference you'll have access to the rock star speakers, the ability to engage with luminaries in the hallways, and have beer (or 2) with community peers in designated areas. Even though the conference is Oct 2-6, 2011, and will be bigger and better than last year's conference, the Call for Paper submission and review/selection evaluation started much earlier.In previous years, I've participated in the review process and this year I was honored to serve as co-lead for the "Enterprise Service Architecture and Cloud" track with Ludovic Champenois. We had a stellar review team with an equal mix of Oracle and external community reviewers. The review process is very overwhelming with the reviewers going through multiple voting iterations on each submission in order to ensure that the selected content is the BEST of the submitted lot. Our ultimate goal was to ensure that the content best represented the track, and most importantly would draw interest and excitement from attendees. As always, the number and quality of submissions were just superb, making for a truly challenging (and rewarding) experience for the reviewers. As co-lead I tried to ensure that I applied a fair and balanced process in the evaluation of content in my track. . Here are some key steps followed by all track leads: Vote on sessions - Each reviewer is required to vote on the sessions on a scale of 1-5 - and also provide a justifying comment. Create buckets - Divide the submissions into different buckets to ensure a fair representation of different topics within a track. This ensures that if a particular bucket got higher votes then the track is not exclusively skewed towards it. Top 7 - The review committee provides a list of the top 7 talks that can be used in the promotional material by the JavaOne team. Generally these talks are easy to identify and a consensus is reached upon them fairly quickly. First cut - Each track is allocated a total number of sessions (including panels), BoFs, and Hands-on labs that can be approved. The track leads then start creating the first cut of the approvals using the casted votes coupled with their prior experience in the subject matter. In our case, Ludo and I have been attending/speaking at JavaOne (and other popular Java-focused conferences) for double digit years. The Grind - The first cut is then refined and refined and refined using multiple selection criteria such as sorting on the bucket, speaker quality, topic popularity, cumulative vote total, and individual vote scale. The sessions that don't make the cut are reviewed again as well to ensure if they need to replace one of the selected one as a potential alternate. I would like to thank the entire Java community for all the submissions and many thanks to the reviewers who spent countless hours reading each abstract, voting on them, and helping us refine the list. I think approximately 3-4 hours cumulative were spent on each submission to reach an evaluation, specifically the border line cases. We gave our recommendations to the JavaOne Program Committee Chairperson (Sharat Chander) and accept/decline notifications should show up in submitter inboxes in the next few weeks. Here are some points to keep in mind when submitting a session to JavaOne next time: JavaOne is a technology-focused conference so any product, marketing or seemingly marketish talk are put at the bottom of the list.Oracle Open World and Oracle Develop are better options for submitting product specific talks. Make your title catchy. Remember the attendees are more likely to read the abstract if they like the title. We try our best to recategorize the talk to a different track if it needs to but please ensure that you are filing in the right track to have all the right eyeballs looking at it. Also, it does not hurt marking an alternate track if your talk meets the criteria. Make sure to coordinate within your team before the submission - multiple sessions from the same team or company does not ensure that the best speaker is picked. In such case we rely upon your "google presence" and/or review committee's prior knowledge of the speaker. The reviewers may not know you or your product at all and you get 750 characters to pitch your idea. Make sure to use all of them, to the last 750th character. Make sure to read your abstract multiple times to ensure that you are giving all the relevant information ? Think through your presentation and see if you are leaving out any important aspects.Also look if the abstract has any redundant information that will not required by the reviewers. There are additional sections that allow you to share information about the speaker and the presentation summary. Use them to blow the horn about yourself and any other relevant details. Please don't say "call me at xxx-xxx-xxxx to find out the details" :-) The review committee enjoyed reviewing the submissions and we certainly hope you'll have a great time attending them. Happy JavaOne!

    Read the article

  • JavaOne 2011: Content review process and Tips for submissions

    - by arungupta
    The Technical Sessions, Birds of Feather, Panels, and Hands-on labs (basically all the content delivered at JavaOne) forms the backbone of the conference. At this year's JavaOne conference you'll have access to the rock star speakers, the ability to engage with luminaries in the hallways, and have beer (or 2) with community peers in designated areas. Even though the conference is Oct 2-6, 2011, and will be bigger and better than last year's conference, the Call for Paper submission and review/selection evaluation started much earlier.In previous years, I've participated in the review process and this year I was honored to serve as co-lead for the "Enterprise Service Architecture and Cloud" track with Ludovic Champenois. We had a stellar review team with an equal mix of Oracle and external community reviewers. The review process is very overwhelming with the reviewers going through multiple voting iterations on each submission in order to ensure that the selected content is the BEST of the submitted lot. Our ultimate goal was to ensure that the content best represented the track, and most importantly would draw interest and excitement from attendees. As always, the number and quality of submissions were just superb, making for a truly challenging (and rewarding) experience for the reviewers. As co-lead I tried to ensure that I applied a fair and balanced process in the evaluation of content in my track. . Here are some key steps followed by all track leads: Vote on sessions - Each reviewer is required to vote on the sessions on a scale of 1-5 - and also provide a justifying comment. Create buckets - Divide the submissions into different buckets to ensure a fair representation of different topics within a track. This ensures that if a particular bucket got higher votes then the track is not exclusively skewed towards it. Top 7 - The review committee provides a list of the top 7 talks that can be used in the promotional material by the JavaOne team. Generally these talks are easy to identify and a consensus is reached upon them fairly quickly. First cut - Each track is allocated a total number of sessions (including panels), BoFs, and Hands-on labs that can be approved. The track leads then start creating the first cut of the approvals using the casted votes coupled with their prior experience in the subject matter. In our case, Ludo and I have been attending/speaking at JavaOne (and other popular Java-focused conferences) for double digit years. The Grind - The first cut is then refined and refined and refined using multiple selection criteria such as sorting on the bucket, speaker quality, topic popularity, cumulative vote total, and individual vote scale. The sessions that don't make the cut are reviewed again as well to ensure if they need to replace one of the selected one as a potential alternate. I would like to thank the entire Java community for all the submissions and many thanks to the reviewers who spent countless hours reading each abstract, voting on them, and helping us refine the list. I think approximately 3-4 hours cumulative were spent on each submission to reach an evaluation, specifically the border line cases. We gave our recommendations to the JavaOne Program Committee Chairperson (Sharat Chander) and accept/decline notifications should show up in submitter inboxes in the next few weeks. Here are some points to keep in mind when submitting a session to JavaOne next time: JavaOne is a technology-focused conference so any product, marketing or seemingly marketish talk are put at the bottom of the list.Oracle Open World and Oracle Develop are better options for submitting product specific talks. Make your title catchy. Remember the attendees are more likely to read the abstract if they like the title. We try our best to recategorize the talk to a different track if it needs to but please ensure that you are filing in the right track to have all the right eyeballs looking at it. Also, it does not hurt marking an alternate track if your talk meets the criteria. Make sure to coordinate within your team before the submission - multiple sessions from the same team or company does not ensure that the best speaker is picked. In such case we rely upon your "google presence" and/or review committee's prior knowledge of the speaker. The reviewers may not know you or your product at all and you get 750 characters to pitch your idea. Make sure to use all of them, to the last 750th character. Make sure to read your abstract multiple times to ensure that you are giving all the relevant information ? Think through your presentation and see if you are leaving out any important aspects.Also look if the abstract has any redundant information that will not required by the reviewers. There are additional sections that allow you to share information about the speaker and the presentation summary. Use them to blow the horn about yourself and any other relevant details. Please don't say "call me at xxx-xxx-xxxx to find out the details" :-) The review committee enjoyed reviewing the submissions and we certainly hope you'll have a great time attending them. Happy JavaOne!

    Read the article

  • Best Method For Evaluating Existing Software or New Software

    How many of us have been faced with having to decide on an off-the-self or a custom built component, application, or solution to integrate in to an existing system or to be the core foundation of a new system? What is the best method for evaluating existing software or new software still in the design phase? One of the industry preferred methodologies to use is the Active Reviews for Intermediate Designs (ARID) evaluation process.  ARID is a hybrid mixture of the Active Design Review (ADR) methodology and the Architectural Tradeoff Analysis Method (ATAM). So what is ARID? ARD’s main goal is to ensure quality, detailed designs in software. One way in which it does this is by empowering reviewers by assigning generic open ended survey questions. This approach attempts to remove the possibility for allowing the standard answers such as “Yes” or “No”. The ADR process ignores the “Yes”/”No” questions due to the fact that they can be leading based on how the question is asked. Additionally these questions tend to receive less thought in comparison to more open ended questions. Common Active Design Review Questions What possible exceptions can occur in this component, application, or solution? How should exceptions be handled in this component, application, or solution? Where should exceptions be handled in this component, application, or solution? How should the component, application, or solution flow based on the design? What is the maximum execution time for every component, application, or solution? What environments can this component, application, or solution? What data dependencies does this component, application, or solution have? What kind of data does this component, application, or solution require? Ok, now I know what ARID is, how can I apply? Let’s imagine that your organization is going to purchase an off-the-shelf (OTS) solution for its customer-relationship management software. What process would we use to ensure that the correct purchase is made? If we use ARID, then we will have a series of 9 steps broken up by 2 phases in order to ensure that the correct OTS solution is purchases. Phase 1 Identify the Reviewers Prepare the Design Briefing Prepare the Seed Scenarios Prepare the Materials When identifying reviewers for a design it is preferred that they be pulled from a candidate pool comprised of developers that are going to implement the design. The believe is that developers actually implementing the design will have more a vested interest in ensuring that the design is correct prior to the start of code. Design debriefing consist of a summary of the design, examples of the design solving real world examples put in to use and should be no longer than two hours typically. The primary goal of this briefing is to adequately summarize the design so that the review members could actually implement the design. In the example of purchasing an OTS product I would attempt to review my briefing prior to its distribution with the review facilitator to ensure that nothing was excluded that should have not been. This practice will also allow me to test the length of the briefing to ensure that can be delivered in an appropriate about of time. Seed Scenarios are designed to illustrate conceptualized scenarios when applied with a set of sample data. These scenarios can then be used by the reviewers in the actual evaluation of the software, All materials needed for the evaluation should be prepared ahead of time so that they can be reviewed prior to and during the meeting. Materials Included: Presentation Seed Scenarios Review Agenda Phase 2 Present ARID Present Design Brainstorm and prioritize scenarios Apply scenarios Summarize Prior to the start of any ARID review meeting the Facilitator should define the remaining steps of ARID so that all the participants know exactly what they are doing prior to the start of the review process. Once the ARID rules have been laid out, then the lead designer presents an overview of the design which typically takes about two hours. During this time no questions about the design or rational are allowed to be asked by the review panel as a standard, but they are written down for use latter in the process. After the presentation the list of compiled questions is then summarized and sent back to the lead designer as areas that need to be addressed further. In the example of purchasing an OTS product issues could arise regarding security, the implementation needed or even if this is this the correct product to solve the needed solution. After the Design presentation a brainstorming and prioritize scenarios process begins by reducing the seed scenarios down to just the highest priority scenarios.  These will then be used to test the design for suitability. Once the selected scenarios have been defined the reviewers apply the examples provided in the presentation to the scenarios. The intended output of this process is to provide code or pseudo code that makes use of the examples provided while solving the selected seed scenarios. As a standard rule, the designers of the systems are not allowed to help the review board unless they all become stuck. When this occurs it is documented and along with the reason why the designer needed to help the review panel back on track. Once all of the scenarios have been completed the review facilitator reviews with the group issues that arise during the process. Then the reviewers will be polled as to efficacy of the review experience. References: Clements, Paul., Kazman, Rick., Klien, Mark. (2002). Evaluating Software Architectures: Methods and Case Studies Indianapolis, IN: Addison-Wesley

    Read the article

  • Windows 7 file-based backup service

    - by Ben Voigt
    I'm looking for a good replacement for Lazy Mirror, since it doesn't support Windows 7 well. Pros: One of the things I really loved about Lazy Mirror is that it always maintains a "full" backup, but does so by only copying modified files. As each file was copied, the old version got archived (moved to an out-of-the-way location). So after mirroring ran, there'd be a complete copy of the file system, which could even be booted if necessary. At the same time, extra space on the backup media was used to store as many older versions of files as possible, without wasting space storing multiple copies of the same version. It seems that with Windows 7 backup, there'd be wasted space storing the same data in both the system image and file backup. It was completely file-based, but also aware of the registry (it had a feature to dump the live registry to hive files in the correct format). The backups were normal NTFS filesystems, no special tool was needed to read them. It automatically cleaned out the oldest previous versions when space ran out (unlike Windows 7 backup which apparently simply starts failing the the backup media fills.) It copied all file attributes including security. Cons: It doesn't deal well with junction points, symbolic links, and hard links. It didn't run as a service without lots of help from firesrv or srvany, and then you couldn't interact with the GUI. Running as a service was necessary to be able to mirror protected OS files. It didn't have open file handling, except for registry hives. I guess that the file-by-file archive and replacement could leave mismatched sets of files, if the mirror was interrupted. This would be the advantage of incremental backup techniques that require old full backup + all intermediate incremental backups to restore. But I don't see this as presenting much of a problem, you'd really only have a boot failure if you had a mixture of pre- and post-service pack files, and I can run a full image backup using another tool before applying a service pack. Does anyone know of a tool that does both full-system backup and storage of old versions of files like Lazy Mirror did (without storing the same data multiple times), and also can run as a service in Windows 7? Free is best of course, but a reasonably priced paid program (e.g. It would be absolutely awesome if it also triggered a backup/mirror pass when a particular external drive was plugged in and generated popup warnings if backups hadn't been run recently)

    Read the article

  • Is there a process-oriented IDE ?

    - by Raveline
    My problem is simple : when I'm programming in an OO paradigm, I'm often having part of a main business process divided in many classes. Which means, if I want to examine the whole functional chain that leads to the output, for debugging or for optimization research, it can be a bit painful. So I was wondering : is there an IDE that let you put a "process tag" on functions coming from different objects, and give you a view of all those functions having the same tag ? edit : To give an example (that I'm making up completely, sorry if it doesn't sound very realistic). Let's say we have the following business process for a HR application : receive a holiday-request by an employee, check the validity of the request, then give an alert to his boss ("one of those lazy programmer wants another day off"); at the same time, let's say the boss will want to have a table of all employee's timetable during the time the employee wants his vacations; then handle the answer of the boss, send a nice little mail to the employee ("No way, lazy bones"). Even if we get rid of everything not purely business-related (mail sending process, db handling to get the useful info, GUI functionalities, and so on), we still have something that doesn't really fit in "one class". I'd like to have an IDE that would give me the opportunity to embrace quickly, at the very least : The function handling the validation of the request by the employee; The function preparing the "timetable" for the boss; The function handling the validation of the request by the boss; I wouldn't put all those functions in the same class (but perhaps that's my mistake ?). This is where my dreamed IDE could be helpful.

    Read the article

  • NHibernate Tools: Visual NHibernate

    - by Ricardo Peres
    You probably know that I’m a big fan of Slyce Software’s Visual NHibernate. To me, it is the best tool for generating your entities and mappings from an existing database (it also allows you to go the other way, but I honestly have never used it that way). What I like most about it: Great support: folks at Slyce always listen to your suggestions, give you feedback in a timely manner, and I was even lucky enough to have some of my suggestions implemented! The templating engine, which is very powerful, and more user-friendly than, for example, MyGeneration’s; one of the included templates is Sharp Architecture; Advanced model validations: it even warns you about having lazy properties declared in non-lazy entities; Integration with NHibernate Validator and generation of validation rules automatically based on the database, or on user-defined model settings; The designer: they opted for not displaying all entities in a single screen, which I think was a good decision; has support for all inheritance strategies (table per class hierarchy, table per class, table per concrete class); Generation of FluentNHibernate mappings as well as hbm.xml. I could name others, but… why don’t you see for yourself? There is a demo version available for downloading. By the way, I am in no way related to Slyce, I just happen to like their software!

    Read the article

  • From Oracle PL/SQL Developer to Java programmer - Is it a good decision? [on hold]

    - by user3554231
    I will explain my question in simple words. I have little over 1 year experience in Oracle. My dream is to be "called" as a 'Developer', be it database developer if not software developer. But right now I don't develop anything neither I am in good touch with PL/SQL and other Oracle Utilites like SQL*LOADER, shell scripting and stuff like that as I am only a System Analyst where I analyze and configure database using SQL queries. To be honest, I know very basic PL/SQL and good knowledge in SQL but that won't ever give me a chance to be a developer as I am lagging way behind the "real" developers knowledge. Now I feel I should learn JAVA as well so that I can cope up with the competition. But I am too scared to learn new things as it will take much more time which will indirectly increase my useless work experince(just analyzing) which values nothing in todays market. Moreover that, I am too lazy to work hard i.e. to study and not to work during office hours. To sum it up I am lazy and confused and scared but I want to learn things as well but don't know if I am intelligent enough to learn whole of PL/SQL or to master any other language. Is there any other way from which I can feel confident? Actually I even feel sometimes that after 2-3 years if I still don't achieve my goal, I won't ever be able to reach my destination. I just want to live my dream of being a developer. Give me some tips and hopes but not false hopes.

    Read the article

  • Do you think Scala will be the dominant JVM langauge, ie be the next Java? [on hold]

    - by user1037729
    From what I've read about Scala do far I think it has some nice features but I do not think it should be "the next Java". It might however end up being the next Java (due to fashion rather than fact) but lets not hope it does not... To me adds a lot of complexity over Java which is a simple and scalable language. Scala Pattern matching allows you to perform some type/value checking in a more concise way, this is possible in Java, Scala's pattern matching has a limit to it, you cannot continuously match deeper and deeper down the object graph, so why not just stick to Java and use decent invariants? Scala provides tuples, easy enough to make in Java, create a static factory method and it all reads nicely too. Scala provides mixins, why not just use composition? I believe Scala implicit's are bad, they can lead to code becoming complex and hard to maintain, explicitness is good. Scala provides closures, well they will be in Java 8 too. Scala has lazy keyword for lazy instantiation, this is easy enough to do in Java by calling a getter which creates the instance when needed, no hidden magic here. Scala can be used with AKKA, well so can Java, there is an Java AKKA implementation. Scala offers addition functional features but these can all be created in Java, there are many frameworks with have implemented functional features in Java. All in all Scala seems to offer is addition complexity and thats it...

    Read the article

  • Count function on tree structure (non-binary)

    - by Spevy
    I am implementing a tree Data structure in c# based (largely on Dan Vanderboom's Generic implementation). I am now considering approach on handling a Count property which Dan does not implement. The obvious and easy way would be to use a recursive call which Traverses the tree happily adding up nodes (or iteratively traversing the tree with a Queue and counting nodes if you prefer). It just seems expensive. (I also may want to lazy load some of my nodes down the road). I could maintain a count at the root node. All children would traverse up to and/or hold a reference to the root, and update a internally settable count property on changes. This would push the iteration problem to when ever I want to break off a branch or clear all children below a given node. Generally less expensive, and puts the heavy lifting what I think will be less frequently called functions. Seems a little brute force, and that usually means exception cases I haven't thought of yet, or bugs if you prefer. Does anyone have an example of an implementation which keeps a count for an Unbalanced and/or non-binary tree structure rather than counting on the fly? Don't worry about the lazy load, or language. I am sure I can adjust the example to fit my specific needs. EDIT: I am curious about an example, rather than instructions or discussion. I know this is not technically difficult...

    Read the article

  • Correct way to inject dependencies in Business logic service?

    - by Sri Harsha Velicheti
    Currently the structure of my application is as below Web App -- WCF Service (just a facade) -- Business Logic Services -- Repository - Entity Framework Datacontext Now each of my Business logic service is dependent on more than 5 repositories ( I have interfaces defined for all the repos) and I am doing a Constructor injection right now(poor mans DI instead of using a proper IOC as it was determined that it would be a overkill for our project). Repositories have references to EF datacontexts. Now some of the methods in the Business logic service require only one of the 5 repositories, so If I need to call that method I would end up instantiating a Service which will instatiate all 5 repositories which is a waste. An example: public class SomeService : ISomeService { public(IFirstRepository repo1, ISecondRepository repo2, IThirdRepository repo3) {} // My DoSomething method depends only on repo1 and doesn't use repo2 and repo3 public DoSomething() { //uses repo1 to do some stuff, doesn't use repo2 and repo3 } public DoSomething2() { //uses repo2 and repo3 to do something, doesn't require repo1 } public DoSomething3() { //uses repo3 to do something, doesn't require repo1 and repo2 } } Now if my I have to use DoSomething method on SomeService I end up creating both IFirstRepository,ISecondRepository and IThirdRepository but using only IFirstRepository, now this is bugging me, I can seem to accept that I am un-necessarily creating repositories and not using them. Is this a correct design? Are there any better alternatives? Should I be looking at Lazy instantiation Lazy<T> ?

    Read the article

  • Could a singleton type replace static methods and classes?

    - by MKO
    In C# Static methods has long served a purpose allowing us to call them without instantiating classes. Only in later year have we became more aware of the problems of using static methods and classes. They can’t use interfaces They can’t use inheritance They are hard to test because you can’t make mocks and stubs Is there a better way ? Obviously we need to be able to access library methods without instantiated classes all the time otherwise our code would become pretty cluttered One possibly solution is to use a new keyword for an old concept: the singleton. Singleton’s are global instances of a class, since they are instances we can use them as we would normal classes. In order to make their use nice and practical we'd need some syntactic sugar however Say that the Math class would be of type singleton instead of an actual class. The actual class containing all the default methods for the Math singleton is DefaultMath, which implements the interface IMath. The singleton would be declared as singleton Math : IMath { public Math { this = new DefaultMath(); } } If we wanted to substitute our own class for all math operations we could make a new class MyMath that inherits DefaultMath, or we could just inherit from the interface IMath and create a whole new Class. To make our class the active Math class, you'd do a simple assignment Math = new MyMath(); and voilá! the next time we call Math.Floor it will call your method. Note that for a normal singleton we'd have to write something like Math.Instance.Floor but the compiler eliminates the need for the Instance property Another idea would be to be able to define a singletons as Lazy so they get instantiated only when they're first called, like lazy singleton Math : IMath What do you think, would it have been a better solution that static methods and classes? Is there any problems with this approach?

    Read the article

  • python- scipy optimization

    - by pear
    In scipy fmin_slsqp (Sequential Least Squares Quadratic Programming), I tried reading the code 'slsqp.py' provided with the scipy package, to find what are the criteria to get the exit_modes 0? I cannot find which statements in the code produce this exit mode? Please help me 'slsqp.py' code as follows, exit_modes = { -1 : "Gradient evaluation required (g & a)", 0 : "Optimization terminated successfully.", 1 : "Function evaluation required (f & c)", 2 : "More equality constraints than independent variables", 3 : "More than 3*n iterations in LSQ subproblem", 4 : "Inequality constraints incompatible", 5 : "Singular matrix E in LSQ subproblem", 6 : "Singular matrix C in LSQ subproblem", 7 : "Rank-deficient equality constraint subproblem HFTI", 8 : "Positive directional derivative for linesearch", 9 : "Iteration limit exceeded" } def fmin_slsqp( func, x0 , eqcons=[], f_eqcons=None, ieqcons=[], f_ieqcons=None, bounds = [], fprime = None, fprime_eqcons=None, fprime_ieqcons=None, args = (), iter = 100, acc = 1.0E-6, iprint = 1, full_output = 0, epsilon = _epsilon ): # Now do a lot of function wrapping # Wrap func feval, func = wrap_function(func, args) # Wrap fprime, if provided, or approx_fprime if not if fprime: geval, fprime = wrap_function(fprime,args) else: geval, fprime = wrap_function(approx_fprime,(func,epsilon)) if f_eqcons: # Equality constraints provided via f_eqcons ceval, f_eqcons = wrap_function(f_eqcons,args) if fprime_eqcons: # Wrap fprime_eqcons geval, fprime_eqcons = wrap_function(fprime_eqcons,args) else: # Wrap approx_jacobian geval, fprime_eqcons = wrap_function(approx_jacobian, (f_eqcons,epsilon)) else: # Equality constraints provided via eqcons[] eqcons_prime = [] for i in range(len(eqcons)): eqcons_prime.append(None) if eqcons[i]: # Wrap eqcons and eqcons_prime ceval, eqcons[i] = wrap_function(eqcons[i],args) geval, eqcons_prime[i] = wrap_function(approx_fprime, (eqcons[i],epsilon)) if f_ieqcons: # Inequality constraints provided via f_ieqcons ceval, f_ieqcons = wrap_function(f_ieqcons,args) if fprime_ieqcons: # Wrap fprime_ieqcons geval, fprime_ieqcons = wrap_function(fprime_ieqcons,args) else: # Wrap approx_jacobian geval, fprime_ieqcons = wrap_function(approx_jacobian, (f_ieqcons,epsilon)) else: # Inequality constraints provided via ieqcons[] ieqcons_prime = [] for i in range(len(ieqcons)): ieqcons_prime.append(None) if ieqcons[i]: # Wrap ieqcons and ieqcons_prime ceval, ieqcons[i] = wrap_function(ieqcons[i],args) geval, ieqcons_prime[i] = wrap_function(approx_fprime, (ieqcons[i],epsilon)) # Transform x0 into an array. x = asfarray(x0).flatten() # Set the parameters that SLSQP will need # meq = The number of equality constraints if f_eqcons: meq = len(f_eqcons(x)) else: meq = len(eqcons) if f_ieqcons: mieq = len(f_ieqcons(x)) else: mieq = len(ieqcons) # m = The total number of constraints m = meq + mieq # la = The number of constraints, or 1 if there are no constraints la = array([1,m]).max() # n = The number of independent variables n = len(x) # Define the workspaces for SLSQP n1 = n+1 mineq = m - meq + n1 + n1 len_w = (3*n1+m)*(n1+1)+(n1-meq+1)*(mineq+2) + 2*mineq+(n1+mineq)*(n1-meq) \ + 2*meq + n1 +(n+1)*n/2 + 2*m + 3*n + 3*n1 + 1 len_jw = mineq w = zeros(len_w) jw = zeros(len_jw) # Decompose bounds into xl and xu if len(bounds) == 0: bounds = [(-1.0E12, 1.0E12) for i in range(n)] elif len(bounds) != n: raise IndexError, \ 'SLSQP Error: If bounds is specified, len(bounds) == len(x0)' else: for i in range(len(bounds)): if bounds[i][0] > bounds[i][1]: raise ValueError, \ 'SLSQP Error: lb > ub in bounds[' + str(i) +'] ' + str(bounds[4]) xl = array( [ b[0] for b in bounds ] ) xu = array( [ b[1] for b in bounds ] ) # Initialize the iteration counter and the mode value mode = array(0,int) acc = array(acc,float) majiter = array(iter,int) majiter_prev = 0 # Print the header if iprint >= 2 if iprint >= 2: print "%5s %5s %16s %16s" % ("NIT","FC","OBJFUN","GNORM") while 1: if mode == 0 or mode == 1: # objective and constraint evaluation requird # Compute objective function fx = func(x) # Compute the constraints if f_eqcons: c_eq = f_eqcons(x) else: c_eq = array([ eqcons[i](x) for i in range(meq) ]) if f_ieqcons: c_ieq = f_ieqcons(x) else: c_ieq = array([ ieqcons[i](x) for i in range(len(ieqcons)) ]) # Now combine c_eq and c_ieq into a single matrix if m == 0: # no constraints c = zeros([la]) else: # constraints exist if meq > 0 and mieq == 0: # only equality constraints c = c_eq if meq == 0 and mieq > 0: # only inequality constraints c = c_ieq if meq > 0 and mieq > 0: # both equality and inequality constraints exist c = append(c_eq, c_ieq) if mode == 0 or mode == -1: # gradient evaluation required # Compute the derivatives of the objective function # For some reason SLSQP wants g dimensioned to n+1 g = append(fprime(x),0.0) # Compute the normals of the constraints if fprime_eqcons: a_eq = fprime_eqcons(x) else: a_eq = zeros([meq,n]) for i in range(meq): a_eq[i] = eqcons_prime[i](x) if fprime_ieqcons: a_ieq = fprime_ieqcons(x) else: a_ieq = zeros([mieq,n]) for i in range(mieq): a_ieq[i] = ieqcons_prime[i](x) # Now combine a_eq and a_ieq into a single a matrix if m == 0: # no constraints a = zeros([la,n]) elif meq > 0 and mieq == 0: # only equality constraints a = a_eq elif meq == 0 and mieq > 0: # only inequality constraints a = a_ieq elif meq > 0 and mieq > 0: # both equality and inequality constraints exist a = vstack((a_eq,a_ieq)) a = concatenate((a,zeros([la,1])),1) # Call SLSQP slsqp(m, meq, x, xl, xu, fx, c, g, a, acc, majiter, mode, w, jw) # Print the status of the current iterate if iprint > 2 and the # major iteration has incremented if iprint >= 2 and majiter > majiter_prev: print "%5i %5i % 16.6E % 16.6E" % (majiter,feval[0], fx,linalg.norm(g)) # If exit mode is not -1 or 1, slsqp has completed if abs(mode) != 1: break majiter_prev = int(majiter) # Optimization loop complete. Print status if requested if iprint >= 1: print exit_modes[int(mode)] + " (Exit mode " + str(mode) + ')' print " Current function value:", fx print " Iterations:", majiter print " Function evaluations:", feval[0] print " Gradient evaluations:", geval[0] if not full_output: return x else: return [list(x), float(fx), int(majiter), int(mode), exit_modes[int(mode)] ]

    Read the article

  • JPA : Add and remove operations on lazily initialized collection behaviour ?

    - by Albert Kam
    Hello, im currently trying out JPA 2 and using Hibernate 3.6.x as the engine. I have an entity of ReceivingGood that contains a List of ReceivingGoodDetail, and has a bidirectional relation. Some related codes for each entity follows : ReceivingGood.java @OneToMany(mappedBy="receivingGood", targetEntity=ReceivingGoodDetail.class, fetch=FetchType.LAZY, cascade = CascadeType.ALL) private List<ReceivingGoodDetail> details = new ArrayList<ReceivingGoodDetail>(); public void addReceivingGoodDetail(ReceivingGoodDetail receivingGoodDetail) { receivingGoodDetail.setReceivingGood(this); } void internalAddReceivingGoodDetail(ReceivingGoodDetail receivingGoodDetail) { this.details.add(receivingGoodDetail); } public void removeReceivingGoodDetail(ReceivingGoodDetail receivingGoodDetail) { receivingGoodDetail.setReceivingGood(null); } void internalRemoveReceivingGoodDetail(ReceivingGoodDetail receivingGoodDetail) { this.details.remove(receivingGoodDetail); } @ManyToOne @JoinColumn(name = "receivinggood_id") private ReceivingGood receivingGood; ReceivingGoodDetail.java : public void setReceivingGood(ReceivingGood receivingGood) { if (this.receivingGood != null) { this.receivingGood.internalRemoveReceivingGoodDetail(this); } this.receivingGood = receivingGood; if (receivingGood != null) { receivingGood.internalAddReceivingGoodDetail(this); } } In my experiements with both of these entities, both adding the detail to the receivingGood's collection, and even removing the detail from the receivingGood's collection, will trigger a query to fill the collection before doing the add or remove. This assumption is based on my experiments that i will paste below. My concern is that : is it ok to do changes on only a little bit of records on the collection, and the engine has to query all of the details belonging to the collection ? What if the collection would have to be filled with 1000 records when i just want to edit a single record ? Here are my experiments with the output as the comment above each method : /* Hibernate: select receivingg0_.id as id9_14_, receivingg0_.creationDate as creation2_9_14_, ... too long Hibernate: select receivingg0_.id as id10_20_, receivingg0_.creationDate as creation2_10_20_, ... too long removing existing detail from lazy collection Hibernate: select details0_.receivinggood_id as receivi13_9_8_, details0_.id as id8_, details0_.id as id10_7_, details0_.creationDate as creation2_10_7_, details0_.modificationDate as modifica3_10_7_, details0_.usercreate_id as usercreate10_10_7_, details0_.usermodify_id as usermodify11_10_7_, details0_.version as version10_7_, details0_.buyQuantity as buyQuant5_10_7_, details0_.buyUnit as buyUnit10_7_, details0_.internalQuantity as internal7_10_7_, details0_.internalUnit as internal8_10_7_, details0_.product_id as product12_10_7_, details0_.receivinggood_id as receivi13_10_7_, details0_.supplierLotNumber as supplier9_10_7_, user1_.id as id2_0_, user1_.creationDate as creation2_2_0_, user1_.modificationDate as modifica3_2_0_, user1_.usercreate_id as usercreate6_2_0_, user1_.usermodify_id as usermodify7_2_0_, user1_.version as version2_0_, user1_.name as name2_0_, user2_.id as id2_1_, user2_.creationDate as creation2_2_1_, user2_.modificationDate as modifica3_2_1_, user2_.usercreate_id as usercreate6_2_1_, user2_.usermodify_id as usermodify7_2_1_, user2_.version as version2_1_, user2_.name as name2_1_, user3_.id as id2_2_, user3_.creationDate as creation2_2_2_, user3_.modificationDate as modifica3_2_2_, user3_.usercreate_id as usercreate6_2_2_, user3_.usermodify_id as usermodify7_2_2_, user3_.version as version2_2_, user3_.name as name2_2_, user4_.id as id2_3_, user4_.creationDate as creation2_2_3_, user4_.modificationDate as modifica3_2_3_, user4_.usercreate_id as usercreate6_2_3_, user4_.usermodify_id as usermodify7_2_3_, user4_.version as version2_3_, user4_.name as name2_3_, product5_.id as id0_4_, product5_.creationDate as creation2_0_4_, product5_.modificationDate as modifica3_0_4_, product5_.usercreate_id as usercreate7_0_4_, product5_.usermodify_id as usermodify8_0_4_, product5_.version as version0_4_, product5_.code as code0_4_, product5_.name as name0_4_, user6_.id as id2_5_, user6_.creationDate as creation2_2_5_, user6_.modificationDate as modifica3_2_5_, user6_.usercreate_id as usercreate6_2_5_, user6_.usermodify_id as usermodify7_2_5_, user6_.version as version2_5_, user6_.name as name2_5_, user7_.id as id2_6_, user7_.creationDate as creation2_2_6_, user7_.modificationDate as modifica3_2_6_, user7_.usercreate_id as usercreate6_2_6_, user7_.usermodify_id as usermodify7_2_6_, user7_.version as version2_6_, user7_.name as name2_6_ from ReceivingGoodDetail details0_ left outer join COMMON_USER user1_ on details0_.usercreate_id=user1_.id left outer join COMMON_USER user2_ on user1_.usercreate_id=user2_.id left outer join COMMON_USER user3_ on user2_.usermodify_id=user3_.id left outer join COMMON_USER user4_ on details0_.usermodify_id=user4_.id left outer join Product product5_ on details0_.product_id=product5_.id left outer join COMMON_USER user6_ on product5_.usercreate_id=user6_.id left outer join COMMON_USER user7_ on product5_.usermodify_id=user7_.id where details0_.receivinggood_id=? after removing try selecting the size : 4 after removing, now flushing Hibernate: update ReceivingGood set creationDate=?, modificationDate=?, usercreate_id=?, usermodify_id=?, version=?, purchaseorder_id=?, supplier_id=?, transactionDate=?, transactionNumber=?, transactionType=?, transactionYearMonth=?, warehouse_id=? where id=? and version=? Hibernate: update ReceivingGoodDetail set creationDate=?, modificationDate=?, usercreate_id=?, usermodify_id=?, version=?, buyQuantity=?, buyUnit=?, internalQuantity=?, internalUnit=?, product_id=?, receivinggood_id=?, supplierLotNumber=? where id=? and version=? detail size : 4 */ public void removeFromLazyCollection() { String headerId = "3b373f6a-9cd1-4c9c-9d46-240de37f6b0f"; ReceivingGood receivingGood = em.find(ReceivingGood.class, headerId); // get existing detail ReceivingGoodDetail detail = em.find(ReceivingGoodDetail.class, "323fb0e7-9bb2-48dc-bc07-5ff32f30e131"); detail.setInternalUnit("MCB"); System.out.println("removing existing detail from lazy collection"); receivingGood.removeReceivingGoodDetail(detail); System.out.println("after removing try selecting the size : " + receivingGood.getDetails().size()); System.out.println("after removing, now flushing"); em.flush(); System.out.println("detail size : " + receivingGood.getDetails().size()); } /* Hibernate: select receivingg0_.id as id9_14_, receivingg0_.creationDate as creation2_9_14_, ... too long Hibernate: select receivingg0_.id as id10_20_, receivingg0_.creationDate as creation2_10_20_, ... too long adding existing detail into lazy collection Hibernate: select details0_.receivinggood_id as receivi13_9_8_, details0_.id as id8_, details0_.id as id10_7_, details0_.creationDate as creation2_10_7_, details0_.modificationDate as modifica3_10_7_, details0_.usercreate_id as usercreate10_10_7_, details0_.usermodify_id as usermodify11_10_7_, details0_.version as version10_7_, details0_.buyQuantity as buyQuant5_10_7_, details0_.buyUnit as buyUnit10_7_, details0_.internalQuantity as internal7_10_7_, details0_.internalUnit as internal8_10_7_, details0_.product_id as product12_10_7_, details0_.receivinggood_id as receivi13_10_7_, details0_.supplierLotNumber as supplier9_10_7_, user1_.id as id2_0_, user1_.creationDate as creation2_2_0_, user1_.modificationDate as modifica3_2_0_, user1_.usercreate_id as usercreate6_2_0_, user1_.usermodify_id as usermodify7_2_0_, user1_.version as version2_0_, user1_.name as name2_0_, user2_.id as id2_1_, user2_.creationDate as creation2_2_1_, user2_.modificationDate as modifica3_2_1_, user2_.usercreate_id as usercreate6_2_1_, user2_.usermodify_id as usermodify7_2_1_, user2_.version as version2_1_, user2_.name as name2_1_, user3_.id as id2_2_, user3_.creationDate as creation2_2_2_, user3_.modificationDate as modifica3_2_2_, user3_.usercreate_id as usercreate6_2_2_, user3_.usermodify_id as usermodify7_2_2_, user3_.version as version2_2_, user3_.name as name2_2_, user4_.id as id2_3_, user4_.creationDate as creation2_2_3_, user4_.modificationDate as modifica3_2_3_, user4_.usercreate_id as usercreate6_2_3_, user4_.usermodify_id as usermodify7_2_3_, user4_.version as version2_3_, user4_.name as name2_3_, product5_.id as id0_4_, product5_.creationDate as creation2_0_4_, product5_.modificationDate as modifica3_0_4_, product5_.usercreate_id as usercreate7_0_4_, product5_.usermodify_id as usermodify8_0_4_, product5_.version as version0_4_, product5_.code as code0_4_, product5_.name as name0_4_, user6_.id as id2_5_, user6_.creationDate as creation2_2_5_, user6_.modificationDate as modifica3_2_5_, user6_.usercreate_id as usercreate6_2_5_, user6_.usermodify_id as usermodify7_2_5_, user6_.version as version2_5_, user6_.name as name2_5_, user7_.id as id2_6_, user7_.creationDate as creation2_2_6_, user7_.modificationDate as modifica3_2_6_, user7_.usercreate_id as usercreate6_2_6_, user7_.usermodify_id as usermodify7_2_6_, user7_.version as version2_6_, user7_.name as name2_6_ from ReceivingGoodDetail details0_ left outer join COMMON_USER user1_ on details0_.usercreate_id=user1_.id left outer join COMMON_USER user2_ on user1_.usercreate_id=user2_.id left outer join COMMON_USER user3_ on user2_.usermodify_id=user3_.id left outer join COMMON_USER user4_ on details0_.usermodify_id=user4_.id left outer join Product product5_ on details0_.product_id=product5_.id left outer join COMMON_USER user6_ on product5_.usercreate_id=user6_.id left outer join COMMON_USER user7_ on product5_.usermodify_id=user7_.id where details0_.receivinggood_id=? after adding try selecting the size : 5 after adding, now flushing Hibernate: update ReceivingGood set creationDate=?, modificationDate=?, usercreate_id=?, usermodify_id=?, version=?, purchaseorder_id=?, supplier_id=?, transactionDate=?, transactionNumber=?, transactionType=?, transactionYearMonth=?, warehouse_id=? where id=? and version=? detail size : 5 */ public void editLazyCollection() { String headerId = "3b373f6a-9cd1-4c9c-9d46-240de37f6b0f"; ReceivingGood receivingGood = em.find(ReceivingGood.class, headerId); // get existing detail ReceivingGoodDetail detail = em.find(ReceivingGoodDetail.class, "323fb0e7-9bb2-48dc-bc07-5ff32f30e131"); detail.setInternalUnit("MCB"); System.out.println("adding existing detail into lazy collection"); receivingGood.addReceivingGoodDetail(detail); System.out.println("after adding try selecting the size : " + receivingGood.getDetails().size()); System.out.println("after adding, now flushing"); em.flush(); System.out.println("detail size : " + receivingGood.getDetails().size()); } Please share your experience on this matter ! Thank you !

    Read the article

  • Why does Scala apply thunks automatically, sometimes?

    - by Anonymouse
    At just after 2:40 in ShadowofCatron's Scala Tutorial 3 video, it's pointed out that the parentheses following the name of a thunk are optional. "Buh?" said my functional programming brain, since the value of a function and the value it evaluates to when applied are completely different things. So I wrote the following to try this out. My thought process is described in the comments. object Main { var counter: Int = 10 def f(): Int = { counter = counter + 1; counter } def runThunk(t: () => Int): Int = { t() } def main(args: Array[String]): Unit = { val a = f() // I expect this to mean "apply f to no args" println(a) // and apparently it does val b = f // I expect this to mean "the value f", a function value println(b) // but it's the value it evaluates to when applied to no args println(b) // and the evaluation happens immediately, not in the call runThunk(b) // This is an error: it's not println doing something funny runThunk(f) // Not an error: seems to be val doing something funny } }   To be clear about the problem, this Scheme program (and the console dump which follows) shows what I expected the Scala program to do. (define counter (list 10)) (define f (lambda () (set-car! counter (+ (car counter) 1)) (car counter))) (define runThunk (lambda (t) (t))) (define main (lambda args (let ((a (f)) (b f)) (display a) (newline) (display b) (newline) (display b) (newline) (runThunk b) (runThunk f)))) > (main) 11 #<procedure:f> #<procedure:f> 13   After coming to this site to ask about this, I came across this answer which told me how to fix the above Scala program: val b = f _ // Hey Scala, I mean f, not f() But the underscore 'hint' is only needed sometimes. When I call runThunk(f), no hint is required. But when I 'alias' f to b with a val then apply it, it doesn't work: the evaluation happens in the val; and even lazy val works this way, so it's not the point of evaluation causing this behaviour.   That all leaves me with the question: Why does Scala sometimes automatically apply thunks when evaluating them? Is it, as I suspect, type inference? And if so, shouldn't a type system stay out of the language's semantics? Is this a good idea? Do Scala programmers apply thunks rather than refer to their values so much more often that making the parens optional is better overall? Examples written using Scala 2.8.0RC3, DrScheme 4.0.1 in R5RS.

    Read the article

  • How to make external Mathematica functions interruptible?

    - by Szabolcs
    I had an earlier question about integrating Mathematica with functions written in C++. This is a follow-up question: If the computation takes too long I'd like to be able to abort it using Evaluation Abort Evaluation. Which of the technologies suggested in the answers make it possible to have an interruptible C-based extension function? How can "interruptibility" be implemented on the C side? I need to make my function interruptible in a way which will corrupt neither it, nor the Mathematica kernel (i.e. it should be possible to call the function again from Mathematica after it has been interrupted)

    Read the article

  • Using Apache Velocity with StringBuilders/CharSequences

    - by mindas
    We are using Apache Velocity for dynamic templates. At the moment Velocity has following methods for evaluation/replacing: public static boolean evaluate(Context context, Writer writer, String logTag, Reader reader) public static boolean evaluate(Context context, Writer out, String logTag, String instring) We use these methods by providing StringWriter to write evaluation results. Our incoming data is coming in StringBuilder format so we use StringBuilder.toString and feed it as instring. The problem is that our templates are fairly large (can be megabytes, tens of Ms on rare cases), replacements occur very frequently and each replacement operation triples the amount of required memory (incoming data + StringBuilder.toString() which creates a new copy + outgoing data). I was wondering if there is a way to improve this. E.g. if I could find a way to provide a Reader and Writer on top of same StringBuilder instance that only uses extra memory for in/out differences, would that be a good approach? Has anybody done anything similar and could share any source for such a class? Or maybe there any better solutions to given problem?

    Read the article

  • C++ coverage tool that WORKS?!

    - by Poni
    Been searching for a good coverage tool for a while now. I'm with VC++ 2008. Tried already: NCover, PureCoverage, PartCover and a few others I can't remember their names. None works! Not even with a very basic console application that does almost nothing. Tried to get an evaluation copy from BullsEye and few more others - not only that they require you to ask for it (no automatic process), they don't even answer after you request AND after you ask what's going on, through the support mail. So the question is: Is there any tool, which I can immediately download an evaluation for it, that actually works on VC 2008 projects? Something that will get me going within 10 minutes? It's funny but it seems to be a very non-trivial request in the area of this kind of software.

    Read the article

  • Top 10 Tips & Tricks for Oracle SQL Developer

    - by thatjeffsmith
    Being a short week due to the holiday, and with everyone enjoying their Summer vacations (apologies Southern Hemispherians), I reckoned it was a great time to do one of those lazy recap-Top 10-Reader’s Digest type posts. I’ve been sharing 1-3 tips or ‘tricks’ a week since I started blogging about SQL Developer, and I have more than enough content to write a book. But since I’m lazy, I’m just going to compile a list of my favorite ‘must know’ tips instead. I always have to leave out a few tips when I do my presentations, so now I can refer back to this list to make sure I’m not forgetting anything. So without further ado… 1. Configure Your Preferences Yes, there are a LOT of options. But you don’t need to worry about all of them just yet. I do recommend you take a quick look at these ones in particular. Whether you’re new to the tool or have been using it for 5 years, don’t overlook these settings! 2. Disable Extensions You Aren’t Using If you’re not using Data Miner, or if you’re not working on a Migration – disable those extensions! SQL Developer will run leaner & meaner, plus the user interface will be a bit more simplified making the tool easier to navigate as well. 3. SQL Recall via Keyboard Access your history via the keyboard! Cycle through your recent SQL statements just using these magic key strokes! Ctrl+Up or Ctrl+Down. 4. Format Your Query Output Directly to CSV, XML, HTML, etc Have the query results pre-formatted in the format of your choice! Too lazy to run the Export wizard for your query result sets? Just add the SQL Developer output hints to your statement and have the output auto-magically formatted to the style of your choice! 5. Drag & Drop Multiple Tables to the Worksheet SQL Developer will auto-join the related objects. You can then toggle over to the Query Builder to toggle off the columns you don’t want to query. I guarantee this tip will save you time if you’re joining 3 or more tables! 6. Drag & Drop Multiple Tables to a Relational Model A pretty picture is worth a few dozen DDL scripts? SQL Developer does data modeling! If you ctrl-drag a table to a model, it will take that table and any related tables and reverse engineer them to a relational model! You can then print it out or export it to HTML, PDF, etc. 7. View Your PL/SQL Execution Output Automatically Function returns a refcursor? Procedure had 3 out parameters? When you run these programs via the Procedure Editor, we automatically capture the output and place them into one or more data grids for you to browse. 8. Disable Automatic Code Insight and Use It On-Demand Code Editor – Completion Insight – Enable Completion Auto-Popup (Keyword being Auto) Some folks really don’t like it when their IDEs or word-processors try to do ‘too much’ for them. Thankfully SQL Developer allows you to either increase the delay before it attempts to auto-complete your text OR to disable the automatic bit. Instead, you can invoke it on-demand. 9. Interactive Debugging – Change Your Variable Values as You Step Through Your PLSQL Watches aren’t just for watching. You can actually interact with your programs and ‘see what happens’ when X = 256 instead of 1. 10. Ditch the Tree View for the Schema Browser There’s nothing wrong with the Connection tree for browsing your database objects. But some folks just can’t seem to get comfortable with it. So, we built them a Schema Browser that uses a drop down control instead for changing up your schema and object types. Already Know This Stuff, Want More? Just check out my SQL Developer resource page, it’s one of the main links on the top of this page. Or if you can’t find something, just drop me a note in the form of a comment on this page and I’ll do my best to find it or write it for you.

    Read the article

< Previous Page | 17 18 19 20 21 22 23 24 25 26 27 28  | Next Page >