Search Results

Search found 46178 results on 1848 pages for 'java home'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 850/1848 | < Previous Page | 846 847 848 849 850 851 852 853 854 855 856 857  | Next Page >

  • Can the JVM recover from an OutOfMemoryError without a restart

    - by askullhead
    Can the JVM recover from an OutOfMemoryError without a restart if it gets a chance to run the GC before more object allocation requests come in? Do the various JVM implementations differ in this aspect? EDIT: My question was about the JVM recovering and not the user program trying to recover by catching the error. In other words if an OOME is thrown in an application server (jboss/websphere/..) do I have to restart it? Or can I let it run if further requests seem to work without a problem. Sorry if that wan't clear.

    Read the article

  • In Intellij, how can I get a List on the left hand side when I extract a variable that's an ArrayList?

    - by tieTYT
    As an example, if I extract a variable from this: return new ArrayList<CrudTestData<Foo>>(); It will turn the code into this: ArrayList<CrudTestData<Foo>> list = new ArrayList<CrudTestData<Foo>>(); return list; How can I automatically get a list on the left hand side like this? List<CrudTestData<Foo>> list = new ArrayList<CrudTestData<Foo>>(); return list; Theoretically, Intellij should know to use a List instead of a Collection because the method returns a List.

    Read the article

  • JBoss Clustered Service that sends emails from txt file

    - by michael lucas
    I need a little push in the right direction. Here's my problem: I have to create an ultra-reliable service that sends email messages to clients whose addresses are stored in txt file on FTP server. Single txt file may contain unlimited number of entries. Most often the file contains about 300,000 entries. Service exposes interface with just two simple methods: TaskHandle sendEmails(String ftpFilePath); ProcessStatus checkProcessStatus(TaskHandle taskHandle); Method sendEmails() returns TaskHandle by which we can ask for ProcessStatus. For such a service to be reliable clustering is necessary. Processing single txt file might take a long time. Restarting one node in a cluster should have no impact on sending emails. We use JBoss AS 4.2.0 which comes with a nice HASingletonController that ensure one instance of service is running at given time. But once a fail-over happens, the second service should continue work from where the first one stopped. How can I share state between nodes in a cluster in such a way that leaves no possibility of sending some emails twice?

    Read the article

  • DataSource or ConnectionPoolDataSource for Application Server JDBC resources

    - by Vinnie
    When creating JNDI JDBC connection pools in an application server, I always specified the type as javax.sql.ConnectionPoolDataSource. I never really gave it too much thought as it always seemed natural to prefer pooled connections over non-pooled. However, in looking at some examples (specifically for Tomcat) I noticed that they specify javax.sql.DataSource. Further, it seems there are settings for maxIdle and maxWait giving the impression that these connections are pooled as well. Glassfish also allows these parameters regardless of the type of data source selected. Are javax.sql.DataSource pooled in an application server (or servlet container)? What (if any) advantages are there for choosing javax.sql.ConnectionPoolDataSource over javax.sql.DataSource (or vice versa)?

    Read the article

  • hibernate for dynamic table creation

    - by user369316
    i AM A HIBERNATE BEGINNER ,Since i need to create dynamic tables with dynamic fields in them i chose to use hibernate . As far as my understanding , creating tables requires a class with the fields defined in the class . How do i generate the classes dynamically based on the table with the required fields ?

    Read the article

  • Google App Engine - What causes cold start latency time to be high, even though my CPU usage is rela

    - by Spines
    I've optimized my code to use only lightweight libraries. I'm even using the low level datastore rather than JDO. And my cold start CPU usage has dropped from about 5 seconds to about 1.5 seconds. However, the time it takes to respond is often about 4.5 seconds, though it varies a lot. Here are some lines from my logs: 03-19 09:16PM 57.368 /donothing 200 4506ms 1516cpu_ms 0kb Mozilla/5.0 03-19 09:22PM 54.884 /donothing 200 4452ms 1477cpu_ms 0kb Mozilla/5.0 What is the app engine doing for those extra 3 seconds that apparently isn't using any CPU?

    Read the article

  • JUnit: checking if a void method gets called

    - by nkr1pt
    I have a very simple filewatcher class which checks every 2 seconds if a file has changed and if so, the onChange method (void) is called. Is there an easy way to check ik the onChange method is getting called in a unit test? code: public class PropertyFileWatcher extends TimerTask { private long timeStamp; private File file; public PropertyFileWatcher(File file) { this.file = file; this.timeStamp = file.lastModified(); } public final void run() { long timeStamp = file.lastModified(); if (this.timeStamp != timeStamp) { this.timeStamp = timeStamp; onChange(file); } } protected void onChange(File file) { System.out.println("Property file has changed"); } } @Test public void testPropertyFileWatcher() throws Exception { File file = new File("testfile"); file.createNewFile(); PropertyFileWatcher propertyFileWatcher = new PropertyFileWatcher(file); Timer timer = new Timer(); timer.schedule(propertyFileWatcher, 2000); FileWriter fw = new FileWriter(file); fw.write("blah"); fw.close(); Thread.sleep(8000); // check if propertyFileWatcher.onChange was called file.delete(); }

    Read the article

  • Correct way to persist Quartz triggers

    - by davioooh
    I'm quite new to Quartz and now I need to schedule some jobs in Spring Web App. I know about Spring + Quartz integration (I'm using Spring v 3.1.1) but I'm wondering if it's the right way to follow. In particular I need to persist my scheduled tasks in a DB so I can re-initialize them when application is restarted. Are there some utilities provided by Spring scheduling wrapper to do this? Can you suggest me some "well known" approach to follow?

    Read the article

  • Partially constructed object / Multi threading

    - by reto
    Heya! I'm using joda due to it's good reputation regarding multi threading. It goes great distances to make multi threaded date handling efficient, for example by making all Date/Time/DateTime objects immutable. But here's a situation where I'm not sure if Joda is really doing the right thing. It probably is correct, but I'd be very interested to see the explanation for it. When a toString() of a DateTime is being called Joda does the following: /* org.joda.time.base.AbstractInstant */ public String toString() { return ISODateTimeFormat.dateTime().print(this); } All formatters are thread safe, as they are as well ready-only. But what's about the formatter-factory: private static DateTimeFormatter dt; /* org.joda.time.format.ISODateTimeFormat */ public static DateTimeFormatter dateTime() { if (dt == null) { dt = new DateTimeFormatterBuilder() .append(date()) .append(tTime()) .toFormatter(); } return dt; } This is a common pattern in single threaded applications. I see the following dangers: Race condition during null check -- worst case: two objects get created. No Problem, as this is solely a helper object (unlike a normal singleton pattern situation), one gets saved in dt, the other is lost and will be garbage collected sooner or later. the static variable might point to a partially constructed object before the objec has been finished initialization (before calling me crazy, read about a similar situation in this Wikipedia article. So how does Joda ensure that not partially created formatter gets published in this static variable? Thanks for your explanations! Reto

    Read the article

  • Accessing FacesContext from Web Service

    - by scriptmonster
    I'm developing a Web Service which will be called by clients which are written by me. In the web service I need to use application-wide objects which eases the load of application on the system. I have implemented my application-wide objects as shown in this question. I can use my object in a jsf page with no problem as follows. MyObject mo = (MyObject) FacesContext.getCurrentInstance().getExternalContext().getApplicationMap().get("MyObjectsName"); But when it comes to use it in a Web Service Request FacesContext.getCurrentInstance() returns null. Is there any way to use the FacesContext in a web service.

    Read the article

  • Counting down to zero in contrast to counting up to length - 1

    - by Helper Method
    Is it recommended to count in small loops (where possible) down from length - 1 to zero instead of counting up to length - 1? 1.) Counting down for (int i = a.length - 1; i >= 0; i--) { if (a[i] == key) return i; } 2.) Counting up for (int i = 0; i < a.length; i++) { if (a[i] == key) return i; } The first one is slightly faster that the second one (because comparing to zero is faster) but is a little more error-prone in my opinion. Besides, the first one could maybe not be optimized by future improvements of the JVM. Any ideas on that?

    Read the article

  • Invoke Maven-Module build from intellij

    - by Roman
    Hi All I was wondering if someone knows a way to invoke a specific maven module build from IntelliJ that will also build ( or use already compiled classes ) from depended modules. So for instance if I would like to build the module "Model" in the picture and only it , it seems reasonable for me to click the package step on it. But what is actually does it invokes the mvn package step inside this specific module rather than "mvn -am -pl module-name" from the root module , which also builds all the dependencies. So is there something that I just don't know ?

    Read the article

  • How can I get jsonp to play nice with my class?

    - by George Edison
    This whole jsonp thing is quite confusing... Here is what I want to do: I have a class DataRetriever The class has a method GetData GetData makes a jsonp request with the following code: var new_tag = document.createElement('script'); new_tag.type = 'text/javascript'; new_tag.src = 'http://somesite.com/somemethod?somedata'; // Add the element var bodyRef = document.getElementsByTagName("body").item(0); bodyRef.appendChild(new_tag); Now, the jsonp data from the server somesite.com can call a function in my code with the data. The problem is, how does the data get delivered to the instance of DataRetriever that requested it? I'm really stuck here.

    Read the article

  • JSF don't find component in view root with the form id

    - by kenzokujpn
    I have a t:inputFileUpload inside the form, in the html of the display page the id of this component is form:inputFile but when I tried to get the component from the view root using "form:inputFile" the return is null, but when the "form:" is removed the return is the component. The component don't set the value in my managed bean, someone have this problem? EDIT: <h:form id="form" enctype="multipart/form-data"> <t:inputFileUpload id="inputFile" size="40" value="#{managedBean.inputFile}"/> </h:form> In the managed bean: private UploadedFile inputFile; with the gets and sets provided by Eclipse. //This method scans the view root and returns the component with the id passed as parameter findComponentInRoot("form:inputFile"); This returns null, but when I use: //This method scans the view root and returns the component with the id passed as parameter findComponentInRoot("inputFile"); The return is the component I'm looking for, but when I use the View Source in Internet Explorer the id of this component is "form:inputFile". I don't know if this is related, but the component don't set the value in my managed bean and it's strange the fact that the id of the component is different from the HTML source. I'm using JSF 1.2 Mojarra. Someone else has this problem? Or know why this happens?

    Read the article

  • How to create new account using servlets

    - by Alvin
    I want to know how can I create new account using servlets in post method? I'm currently following MVC design pattern, and I want to know if I pass the required data to register new account from JSP page, then how can I get that data in post method? As request.getParameter() method returning me null. How can I know that post method is calling to create new account? How can I pass all the relevant user information from servlets to model class for registering data to the database table?

    Read the article

  • Using inheritance and polymorphism to solve a common game problem

    - by Barry Brown
    I have two classes; let's call them Ogre and Wizard. (All fields are public to make the example easier to type in.) public class Ogre { int weight; int height; int axeLength; } public class Wizard { int age; int IQ; int height; } In each class I can create a method called, say, battle() that will determine who will win if an Ogre meets and Ogre or a Wizard meets a Wizard. Here's an example. If an Ogre meets an Ogre, the heavier one wins. But if the weight is the same, the one with the longer axe wins. public Ogre battle(Ogre o) { if (this.height > o.height) return this; else if (this.height < o.height) return o; else if (this.axeLength > o.axeLength) return this; else if (this.axeLength < o.axeLength) return o; else return this; // default case } We can make a similar method for Wizards. But what if a Wizard meets an Ogre? We could of course make a method for that, comparing, say, just the heights. public Wizard battle(Ogre o) { if (this.height > o.height) return this; else if (this.height < o.height) return o; else return this; } And we'd make a similar one for Ogres that meet Wizard. But things get out of hand if we have to add more character types to the program. This is where I get stuck. One obvious solution is to create a Character class with the common traits. Ogre and Wizard inherit from the Character and extend it to include the other traits that define each one. public class Character { int height; public Character battle(Character c) { if (this.height > c.height) return this; else if (this.height < c.height) return c; else return this; } } Is there a better way to organize the classes? I've looked at the strategy pattern and the mediator pattern, but I'm not sure how either of them (if any) could help here. My goal is to reach some kind of common battle method, so that if an Ogre meets an Ogre it uses the Ogre-vs-Ogre battle, but if an Ogre meets a Wizard, it uses a more generic one. Further, what if the characters that meet share no common traits? How can we decide who wins a battle?

    Read the article

  • Using collections/containers/catalogs in Domain Models

    - by devoured elysium
    Let's say I want to model a cinema. The cinema will have a couple of rooms(for example, 7), where the movies are being played. I wonder how should I design the domain model for this scenario. Should the Cinema class concept concept have a direct association with the 7 rooms? Should the Cinema class concept have an association with a catalog of the 7 rooms? Why? I am having some trouble understanding why in some places I see the first case and in some others I see something like the second case. If instead of rooms, I wanted to depict the relationship between Cinema and: Tickets to sell (today). Tickets already sold (today) Customers in the Cinema database The set of hours at which there are movies playing in a given room in the cinema. The set of places you can sit at in a room in the cinema. Should I use catalogs, should I connect them directly to the Cinema concept with a multiplicity of * in the target? Thanks

    Read the article

  • Stripes link event triggering validation that is incorrect.

    - by Davoink
    I have stripes:link tag in a jsp with an event attribute: <stripes:link href="${actionBean.context.currentStage.stripesForwardAction}" addSourcePage="true" event="showTab2Link"> This triggers the validation to trigger on nested properties: @ValidateNestedProperties({ @Validate(field="county", required=true, minlength=2, maxlength=2, mask="\\d\\d"), @Validate(field="parish", required=true, minlength=3, maxlength=3, mask="\\d\\d\\d"), @Validate(field="holding", required=true, minlength=4, maxlength=4, mask="\\d\\d\\d\\d") }) However this would been fine if the actual values it is validation are not present, but they are present within the html and when debugging the bean. Why would the stripes:link trigger this? If I change it to an stripes:submit then it is fine. thanks, Dave

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 846 847 848 849 850 851 852 853 854 855 856 857  | Next Page >