Search Results

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

Page 864/1848 | < Previous Page | 860 861 862 863 864 865 866 867 868 869 870 871  | Next Page >

  • Shortcut for adding to List in a HashMap

    - by Damo
    I often have a need to take a list of objects and group them into a Map based on a value contained in the object. Eg. take a list of Users and group by Country. My code for this usually looks like: Map<String, List<User>> usersByCountry = new HashMap<String, List<User>>(); for(User user : listOfUsers) { if(usersByCountry.containsKey(user.getCountry())) { //Add to existing list usersByCountry.get(user.getCountry()).add(user); } else { //Create new list List<User> users = new ArrayList<User>(1); users.add(user); usersByCountry.put(user.getCountry(), users); } } However I can't help thinking that this is awkward and some guru has a better approach. The closest I can see so far is the MultiMap from Google Collections. Are there any standard approaches? Thanks!

    Read the article

  • Finding days between two dates

    - by Ram
    I need to get all the dates between two dates For example Start date : 04/06/2010 End Date : 10/06/2010 Then, it has to list out 05/06/2010 06/06/2010 07/06/2010 08/06/2010 09/06/2010 Thanks

    Read the article

  • Hibernate updating records and implementing listeners : getting only required attribute values for event.getOldState()

    - by Narendra
    Hi All, I am using Hibernate 3 as my persistence framework. Below is the sample hbm file I am using. <?xml version="1.0"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping> <class name="com.test.User" table="user"> <meta attribute="implements">com.test.dao.interfaces.IEntity</meta> <id name="key" type="long" column="user_key"> <generator class="increment" /> </id> <property name="userName" column="user_name" not-null="true" type="string" /> <property name="password" column="password" not-null="true" type="string" /> <property name="firstName" column="first_name" not-null="true" type="string" /> <property name="lastName" column="last_name" not-null="true" type="string" /> <property name="createdDate" column="created_date" not-null="true" type="timestamp" insert="false" update="false" /> <property name="createdBy" column="created_by" not-null="true" type="string" update="false" /> </class> </hibernate-mapping> I am added a post-update listener. What it will do is if there any updations perfomed on User then it will be invoked and cahnges will be inserted to audit table. Below is the sample implementation for postupdate event. public void onPostUpdate(PostUpdateEvent event) { LogHelper.info(logger, "Begin - onPostUpdate " + event.getEntity().getClass().getSimpleName()); if (!this.checkForAudit(event.getEntity().getClass().getSimpleName())) { // check do we need to audit it. } // Get Attribute Names String[] attrNames = event.getPersister().getEntityMetamodel() .getPropertyNames(); Object[] oldobjectValue = c Object[] newObjectValue = event.getState(); this.auditDetailsEvent(attrNames, oldobjectValue, newObjectValue); LogHelper.info(logger, "End - onPostUpdate"); // return false; } Here is my requirement. event.getPersister().getEntityMetamodel() .getPropertyNames(); or event.getOldState(); or event.getState(); must return attribute names or value which i can update or insert. Is there any way to control the return values of above one's. Pleas help me on this regard. Thanks, Narendra

    Read the article

  • Eager fetching of children with JDO (Datanucleus)

    - by Jan
    Hi, can JDO fetch all children of a database model at once? Like: class Parent { @Persistent(mappedBy="parent") private Set<Children> children; } class Children { @Persistent private Parent parent; @Persistent private String name; } In my case, I have a large number of Parents which I fetch at once. Accessing their children then takes a lot of time because they are fetched lazily. Does JDO (Datanucleus) support their fetching at once, togehter with the Parents? I also tried to fetch all Children independantly with another quey and put them into the Level2 cache afterwards, but still they are fetched (maybe jdo doesn't know about their relationship? Because the ForeignKey (parent-id) hasn't been fetched at first?) Any ideas how to read the data structure faster? Cheers, Jan

    Read the article

  • Accessing global variable in multithreaded Tomcat server

    - by jwegan
    I have a singleton object that I construct like thus: private static volatile KeyMapper mapper = null; public static KeyMapper getMapper() { if(mapper == null) { synchronized(Utils.class) { if(mapper == null) { mapper = new LocalMemoryMapper(); } } } return mapper; } The class KeyMapper is basically a synchronized wrapper to HashMap with only two functions, one to add a mapping and one to remove a mapping. When running in Tomcat 6.24 on my 32bit Windows machine everything works fine. However when running on a 64 bit Linux machine (CentOS 5.4 with OpenJDK 1.6.0-b09) I add one mapping and print out the size of the HashMap used by KeyMapper to verify the mapping got added (i.e. verify size = 1). Then I try to retrieve the mapping with another request and I keep getting null and when I checked the size of the HashMap it was 0. I'm confident the mapping isn't accidentally being removed since I've commented out all calls to remove (and I don't use clear or any other mutators, just get and put). The requests are going through Tomcat 6.24 (configured to use 200 threads with a minimum of 4 threads) and I passed -Xnoclassgc to the jvm to ensure the class isn't inadvertently getting garbage collected (jvm is also running in -server mode). I also added a finalize method to KeyMapper to print to stderr if it ever gets garbage collected to verify that it wasn't being garbage collected. I'm at my wits end and I can't figure out why one minute the entry in HashMap is there and the next it isn't :(

    Read the article

  • How a servlet can get the absolute path to a file outside of the servlet?

    - by WolfmanDragon
    We have been using System.getProperties("user.dir") to get the location of a properties file. Now that it has been deployed on Tomcat(via servlet), the System call is giving the location as tomcat and not at the location at where the properties file exist. How can we call the the properties file dynamically? Given: Tomcat is not the only way the app will be deployed We have no control on where the app may be placed. Relative paths will not work as that Vista is being used and Vista breaks relative paths. This must work on all OS, including(but not limited to) Linux, XP and Vista. EDIT I implied this, but in case I was not clear enough, I have no way of knowing the path String.

    Read the article

  • Spring overloaded constructor injection

    - by noob
    This is the code : public class Triangle { private String color; private int height; public Triangle(String color,int height){ this.color = color; this.height = height; } public Triangle(int height ,String color){ this.color = color; this.height = height; } public void draw() { System.out.println("Triangle is drawn , + "color:"+color+" ,height:"+height); } } The Spring config-file is : <bean id="triangle" class="org.tester.Triangle"> <constructor-arg value="20" /> <constructor-arg value="10" /> </bean> Is there any specific rule to determine which constructor will be called by Spring ?

    Read the article

  • Couldn't copy package file to temp file in android

    - by Siva K
    hi i created a new app, whenever i try to run in my device it shows as [2011-02-17 18:57:09 - SpeedApp02] Installation error: INSTALL_FAILED_MEDIA_UNAVAILABLE [2011-02-17 18:57:09 - SpeedApp02] Please check logcat output for more details. [2011-02-17 18:57:10 - SpeedApp02] Launch canceled! in the console and 02-17 18:58:58.540: ERROR/PackageManager(59): Couldn't copy package file to temp file. in the logcat. What it means? what is the problem. This is the same with emulator too....

    Read the article

  • How to comment in jspx page

    - by ricky
    How to comment the code in jspx page? I have tried several methods, <%-- --, but it doesn't not work! So I have to: code, it is really urgly, Is there any other ways? Any help is appreciated!

    Read the article

  • Syncronizing mobile phone contacts with contacts from social networks

    - by Pentium10
    I retrieve a JSON list of contacts from a social network site. It contains firstname, lastname, displayname, data1, data2, etc... What is the efficient way to quickly lookup my local phone contacts database and "match" them based on their name. Since there are firstname, lastname and displayname this can vary. What do you think, how can the best match be achieved? Also how do I make sure I don't parse for each JSON item the whole database I want to avoide having JSON_COUNT x MOBILE COUNT steps.

    Read the article

  • GF 3.0.1 + Virtual Server: www.myhost.com:8080/projectname-war => www.myhost.com. How?

    - by Harry Pham
    EDIT I need to change www.myhost.com:8080/myproject-war to www.myhost.com. Here is what I've been trying: I configurate the Virtual Server: server. I have still have default Network Listeners to be http-listener-1 and http-listner-2. I change the Default Web Module to ScholarActive#ScholarActive-war.war (The only option in the drop down list, since I only deploy 1 application). For the docroot, I try this ${com.sun.aas.instanceRoot}/applications/ScholarActive/ScholarActive-war_war or this ${com.sun.aas.instanceRoot}/applications/ScholarActive/ Both does not work. What does docroot need to point to, for this to work? what I try to do is: when I type localhost:8080/ScholarActive-war, then my application load, I want to make so that if I type locahost:8080, it will load the app as well, then what left is changed the port to 80. But no luck. Any Idea?

    Read the article

  • How to remove duplicate line in a file

    - by Abs
    Hi I'm using the below method to write to a file from the Jtextarea and I call this method every 30 second within a Timer but instead to add only new line in file it rewrite the entire lines contained in Jtextarea so then I have duplicate lines. I want to avoid this and update the file just with new lines. Could you help me please. public void loger() { FileWriter writer = null; try { writer = new FileWriter("MBM_Log_"+date()+".txt" , true); textArea.write(writer); } catch (IOException exception) { System.err.println("log error"); exception.printStackTrace(); } finally { if (writer != null) { try { writer.close(); } catch (IOException exception) { System.err.println("Error closing writer"); exception.printStackTrace(); } } } }

    Read the article

  • Relation many-to-many with attributes : how ?

    - by mada
    Hi, Excuse me for my poor english in advance as it is not my mother tongue. Like in this example: http://www.xylax.net/hibernate/manytomany.html But i have in the table foo-bar 2 attributes which are not part of the primary or foreign keys.: one boolean(A) & one string(B). I know how to map it without attributes but not in this case. I have not found an answer in the documentation. I need to know please how to map it & what kind of collection i have to declare in my class Foo. Thanks in advance for your answer. I really appreciate the time given by you.

    Read the article

  • JavaME - LWUIT images eat up all the memory

    - by Marko
    Hi, I'm writing a MIDlet using LWUIT and images seem to eat up incredible amounts of memory. All the images I use are PNGs and are packed inside the JAR file. I load them using the standard Image.createImage(URL) method. The application has a number of forms and each has a couple of labels an buttons, however I am fairly certain that only the active form is kept in memory (I know it isn't very trustworthy, but Runtime.freeMemory() seems to confirm this). The application has worked well in 240x320 resolution, but moving it to 480x640 and using appropriately larger images for UI started causing out of memory errors to show up. What the application does, among other things, is download remote images. The application seems to work fine until it gets to this point. After downloading a couple of PNGs and returning to the main menu, the out of memory error is encountered. Naturally, I looked into the amount of memory the main menu uses and it was pretty shocking. It's just two labels with images and four buttons. Each button has three images used for style.setIcon, setPressedIcon and setRolloverIcon. Images range in size from 15 to 25KB but removing two of the three images used for every button (so 8 images in total), Runtime.freeMemory() showed a stunning 1MB decrease in memory usage. The way I see it, I either have a whole lot of memory leaks (which I don't think I do, but memory leaks aren't exactly known to be easily tracked down), I am doing something terribly wrong with image handling or there's really no problem involved and I just need to scale down. If anyone has any insight to offer, I would greatly appreciate it.

    Read the article

  • dynamically change bitmap in imageView, android

    - by Junfei Wang
    All, I have a problem related to imageView, android. I have array which contains of 10 bitmap objects, called bm. I have a imageView, called im. Now I wanna show the bitmaps in the array in im one by one, so I did the following: new Thread(new Runnable() { public void run() { for(int j=0;j<10;j++){ im.setImageBitmap(bm[j]); } } }).start(); But the result only shows the last bitmap in the array. Can someone tell me what to do with this issue? Millions of thanks!

    Read the article

  • Avoid having a huge collection of ids by calling a DAO.getAll()

    - by Michael Bavin
    Instead of returning a List<Long> of ids when calling PersonDao.getAll() we wanted not to have an entire collection of ids in memory. Seems like returning a org.springframework.jdbc.support.rowset.SqlRowSet and iterate over this rowset would not hold every object in memory. The only problem here is i cannot cast this row to my entity. Is there a better way for this?

    Read the article

  • Where about should my main class be created in a project?

    - by Dan
    The problem is where a class should be created in my code. An example is I have a UI class and a main logic class that controls other objects. Should the main logic class create the UI object, or should the UI object create the instance of the main logic class? An explanation of which method is best and why would be ideal. Thanks.

    Read the article

  • Creating a table with an initial element selected

    - by Tony
    I want to create a table which displays in each row a set of data, in addition to a radio button for possible selection. This can be achieved easily by using a simple table model class which extends the DefaultTableModel and a cell renderer and editor class which implements the TableCellRenderer and TableCellEditor interfaces respectively. What I really couldn't manage to do is to make the table to display initially one of the elements (rows) initially selected. It seems straightforward but it isn't...does anybody have a clue about it?

    Read the article

< Previous Page | 860 861 862 863 864 865 866 867 868 869 870 871  | Next Page >