Search Results

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

Page 986/1848 | < Previous Page | 982 983 984 985 986 987 988 989 990 991 992 993  | Next Page >

  • Can I have a set containing identical elements?

    - by Roman
    It is convenient for me to use a set. I like how I can "add" ("remove") an element to (from) the set. It is also convenient to check if a given element is in the set. The only problem, I found out that I cannot add a new element to a set if the set has already such an element. Is it possible to have "sets" which can contain several identical elements.

    Read the article

  • How do I ensure my abstract class's function can only operate on extenders of the same type as the c

    - by incrediman
    For example, let's say this is my abstract class: abstract class A{ int x; int y; void foo(A fooMe); } ...and B and C are two classes which extend A. What I want is for B to only be able to call foo() on other Bs, and for C to only be able to call foo() on other Cs. But I want this to be out of the hands of the programmer who's extending my A class - that is, I want a way to ensure this functionality within As code alone. What can I do? (If possible) I'd like to avoid any hack or generics solution that's too messy - I still want foo to be able to be called like this, for example: B b=new B(); B bb=new B(); bb.foo(b);

    Read the article

  • Android - Opening phone deletes app state

    - by Tom G
    Hey everyone, I'm writing an android application that maintains a lot of "state" data...some of it I can save in the form of onSaveInstanceState but some of it is just to complex to save in memory. My problem is that sliding the phone open destroys/recreates the app, and I lose all my application state in the process. The same thing happens with the "back" button, but I overloaded that function on my way. Is there any way to overload the phone opening to prevent it from happening? Thanks in advance.

    Read the article

  • Regular Expression Program

    - by david robers
    Hi I have the following text: SMWABCCA ABCCAEZZRHM NABCCAYJG XABCCA ABCCADK ABCCASKIYRH ABCCAKY PQABCCAK ABCCAKQ This method takes a regex in out by the user and SHOULD print out the Strings it applies to but seems to print out something completely different: private void matchIt(String regex) { Pattern p = Pattern.compile(regex); Matcher m = null; boolean found = false; for(int i = 0; i < data.length; i++){ m = p.matcher(data[i]); if(m.find()){ out.println(data[i]); found = true; } } if(!found){ out.println("Pattern Not Found"); } } When inputting "[C]" It outputs: SMWABCCA ABCCAEZZRHM NABCCAYJG XABCCA ABCCADK ABCCASKIYRH ABCCAKY PQABCCAK ABCCAKQ Any ideas why? I think I'm using m.find() improperly...

    Read the article

  • Will this be garbage collected in JVM?

    - by stjowa
    I am running the following code every two minutes via a Timer: object = new Object(this); Potentially, this is a lot of objects being created and a lot of objects being overwritten. Do the overwritten objects get garbage collected, even with a reference to itself being used in the newly created object? I am using JDK 1.6.0_13. Thanks for the help.

    Read the article

  • What exactly is GRASP's Controller about?

    - by devoured elysium
    What is the idea behind Grasp's Controller pattern? My current interpretation is that sometimes you want to achieve something that needs to use a couple of classes but none of those classes could or has access to the information needed to do it, so you create a new class that does the job, having references to all the needed classes(this is, could be the information expert). Is this a correct view of what Grasp's Controller is about? Generally when googling or SO'ing controller, I just get results about MVC's (and whatnot) which are topics that I don't understand about, so I'd like answers that don't assume I know ASP.NET's MVC or something :( Thanks

    Read the article

  • Specifiy classpath for maven

    - by Zombies
    Quite new to maven here so let me explain first what I am trying to do: We have certain JAR files which will not be added to the repo. This is because they are specific to Oracle ADF and are already placed on our application server. There is only 1 version to be used for all apps at anyone time. In order to compile though, we need to have these on the class path. There are a LOT of these JARS, so if we were to upgrade to a newer version of ADF, we would have to go into every application and redefine some pretty redundant dependencies. So again, my goal is to just add these JARs to the classpath, since we will control what version is actually used elsewhere. So basically, I want to just add every JAR in a given directory to maven's classpath for when it compiles. And without putting any of these JAR files in a repository. And of course, these JARs are not to be packaged into any EAR/WAR.

    Read the article

  • How much memory does a hashtable use?

    - by Michael
    Would a hashtable/hashmap use a lot of memory if it only consists of object references and int's? As for a school project we had to map a database to objects (that's what being done by orm/hibernate nowadays) but eager to find a good way not to store id's in objects in order to save them again we thought of putting all objects we created in a hashmap/hashtable, so we could easily retrieve it's ID. My question is if it would cost me performance using this, in my opinion more elegant way to solve this problem.

    Read the article

  • returning a Void object

    - by Robert
    What is the correct way to return a Void type, when it isn't a primitive? Eg. I currently use null as below. interface B<E>{ E method(); } class A implements B<Void>{ public Void method(){ // do something return null; } }

    Read the article

  • Mobile Aps that will detect/accept incoming SMS msg?

    - by user848682
    Im working on my thesis and I need some help. My thesis is like some "automated replying system for mobile apps". My questions: 1st: How to make an application that can detect incoming message? ( even some sample documentation will do, Ill d own my research ) 2nd: Is there any tool I need to achieve this? 3rd: What language is usally used for mobile application programming? 4th: Is it possible to achieve this? Thanks in Advance : ) Sorry I dont have any knowledge in mobile aps programming.

    Read the article

  • Is it possible to Hide Text through a Style?

    - by Sandro
    I currently have a JTextPane that will be displaying text coming in from different streams. The way that the user can tell which stream the text came from is that the text from each stream has a different Style to it. Is there a way to make a Style that will hide the text so that I can filter out different pieces of text? Thank you.

    Read the article

  • How do I remove an old JPanel and add a new one?

    - by Roman
    I would like to remove an old JPanel from the Window (JFrame) and add a new one. How should I do it? I tried the following: public static void showGUI() { JFrame frame = new JFrame("Colored Trails"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.add(partnerSelectionPanel); frame.setSize(600,400); frame.setVisible(true); } private static void updateGUI(final int i, final JLabel label, final JPanel partnerSelectionPanel) { SwingUtilities.invokeLater( new Runnable() { public void run() { label.setText(i + " seconds left."); } partnerSelectionPanel.setVisible(false); \\ <------------ } ); } So, my code update the "old" JPanel and them it makes the whole JPanel invisible. It was the idea. But it does not work. The compiler complains about the line indicated with "<------------". It writes: <identifier> expected, illegal start of type.

    Read the article

  • Best practice when removing entity regarding mappedBy collections?

    - by Daniel Bleisteiner
    I'm still kind of undecided which is the best practice to handle em.remove(entity) with this entity being in several collections mapped using mappedBy in JPA. Consider an entity like a Property that references three other entities: a Descriptor, a BusinessObject and a Level entity. The mapping is defined using @ManyToOne in the Property entity and using @OneToMany(mappedBy...) in the other three objects. That inverse mapping is defined because there are some situations where I need to access those collections. Whenever I remove a Property using em.remove(prop) this element is not automatically removed from managed entities of the other three types. If I don't care about that and the following page load (webapp) doesn't reload those entities the Property is still found and some decisions might be taken that are no longer true. The inverse mappings may become quite large and though I don't want to use something like descriptor.getProperties().remove(prop) because it will load all those properties that might have been lazy loaded until then. So my currently preferred way is to refresh the entity if it is managed: if (em.contains(descriptor)) em.refresh(descriptor) - which unloads a possibly loaded collection and triggers a reload upon the next access. Is there another feasible way to handle all those mappedBy collections of already loaded entites?

    Read the article

  • Why do I have to give an identifier?

    - by Knowing me knowing you
    In code: try { System.out.print(fromClient.readLine()); } catch(IOException )//LINE 1 { System.err.println("Error while trying to read from Client"); } In code line marked as LINE 1 compiler forces me to give an identifier even though I'm not using it. Why this unnatural constrain? And then if I type an identifier I'm getting warning that identifier isn't used. It just doesn't make sense to me, forcing a programmer to do something unnecesarry and surplus. And after me someone will revise this code and will be wondering if I didn't use this variable on purpouse or I just forgot. So in order to avoid that I have to write additional comment explaining why I do not use variable which is unnecessary in my code. Thanks

    Read the article

  • Should i use lock.lock(): in this method?

    - by user962800
    I wrote this method whose purpose is to give notice of the fact that a thread is leaving a specific block of code A thread stands for a car which is leaving a bridge so other cars can traverse it . The bridge is accessible to a given number of cars (limited capacity) and it's one way only. public void getout(int diection){ // release the lock semaphore.release(); try{ lock.lock(); //access to shared data if(direction == Car.NORTH) nNordTraversing--; //decreasing traversing threads else nSudTraversing--; bridgeCond.signal(); }finally{ lock.unlock(); } } My question is: should I use lock.lock(); or it's just nonsense? thanks in advance

    Read the article

  • Can I get the full query that a PreparedStatement is about to execute?

    - by ufk
    I'm working with PreparedStatement with MySQL server. example: String myQuery = "select id from user where name = ?"; PreparedStatement stmt = sqlConnection.prepareStatement(myQuery); stmt.setString(1, "test"); stmt.executeQUery(); ResultSet rs = stmt.getResultSet(); How can I receive the full SQL query that is about to be executed on the MySQL server? thanks!

    Read the article

  • sort a list of objects based on runtime property

    - by jijo
    I have an arraylist of VOs. These objects have many properties and corresponding get/set methods. I want to sort this array list based on a property which I'll be getting in runtime. Let me explain in detail. My VO is like this public class Employee { String name; String id; private String getName() { return name; } private String getId() { return id; } } I will be getting a string ‘sort’ in runtime, which can be either ‘id’ of ‘name’. I want to sort the list based on the value of the string. I have tried to use comparator and reflection together, but no luck. I don’t want to use an if loop and create new comparator classes. Any other thoughts?

    Read the article

  • How to manage a BorderLayout with generic JPanel()

    - by Nick G.
    Im not sure how to reference to JPanel when it was declared like this, I had someone else help me on JPanels and this is the code he used: final JFrame frame = new JFrame("CIT Test Program"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setPreferredSize(new Dimension(350, 250)); frame.add(new JPanel() {{ Not sure how to reference to JPanel to use BorderLayout. How would I go about doing this?

    Read the article

  • WeakHashMap iteration and garbage collection

    - by Shamik
    I am using a WeaekHashMap to implement a Cache. I am wondering if I am iterating over the keys of this map, and at the same time garbage collector is actively removing keys from this map, would I receive a ConcurrentModificationException ? I do not think so, because as far as I understand, concurrentmodificationexception happens because of bugs in the application code where the developer forgot to understand that the same map is shared/used by other threads and in this case, it should not happen. But wondering how would JVM handle this when WeakHashMap is not synchronized ?

    Read the article

  • JVM with no garbage collection

    - by HH
    I've read in many threads that it is impossible to turn off garbage collection on Sun's JVM. However, for the purpose of our research project we need this feature. Can anybody recommend a JVM implementation which does not have garbage collection or which allows turning it off? Thank you.

    Read the article

  • Format String become 0001, 0010 etc

    - by trycatch4j
    Hi all.., I have number : 1, 2, 3, 4, 10 But I wanna print that number 0001 0002 0003 0004 0010 I have search in google, the keyword is number format. but I've got nothing, I just get, frmat decimal such ass 1,000,000.00. hope you can suggest me a reference or give me some problem solving. Thanks,

    Read the article

< Previous Page | 982 983 984 985 986 987 988 989 990 991 992 993  | Next Page >