Search Results

Search found 33433 results on 1338 pages for 'java annotations'.

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 305/1338 | < Previous Page | 301 302 303 304 305 306 307 308 309 310 311 312  | Next Page >

  • how can i acess a variable outside of an if statement in java

    - by themanepalli
    i have defined a variable inside an if statement and I am trying to access it outside of that if statement now. now the error is saying that it cannot find the symbol which is because its being defined as an intance variable, is there a way i can change it so i can access it outside the variable? heres the code if((e.getSource()==userOrder2)&& (orderType==1)) { String buyO= userOrder2.getText(); int buyOrder= Integer.parseInt(buyO); //variable im trying to access } // trying to use buyOrder in a different if statement if(orderType==1 && (stockPrice <= buyOrder)) { orderResult.setText("The Stock" + (stockName2.getText()) + "was bought at" + stockPrice); }

    Read the article

  • Java: when to use static methods

    - by KP65
    Hello, I am wondering when to use static methods? Say If i have a class with a few getters and setters, a method or two, and i want those methods only to be invokable on an instance object of the class. Does this mean i should use a static method? e.g Obj x = new Obj(); x.someMethod or Obj.someMethod (is this the static way?) I'm rather confused!

    Read the article

  • Setting the height of a row in a JTable in java

    - by Douglas Grealis
    I have been searching for a solution to be able to increase the height of a row in a JTable. I have been using the setRowHeight(int int) method which compiles and runs OK, but no row[s] have been increased. When I use the getRowHeight(int) method of the row I set the height to, it does print out the size I increased the row to, so I'm not sure what is wrong. The code below is a rough illustration how I am trying to solve it. My class extends JFrame. String[] columnNames = {"Column 1", "Column 2", "Column 1 3"}; JTable table = new JTable(new DefaultTableModel(columnNames, people.size())); DefaultTableModel model = (DefaultTableModel) table.getModel(); int count =1; for(Person p: people) { model.insertRow(count,(new Object[]{count, p.getName(), p.getAge()+"", p.getNationality})); count++; } table.setRowHeight(1, 15);//Try set height to 15 (I've tried higher) Can anyone tell me where I am going wrong? I am trying to increase the height of row 1 to 15 pixels?

    Read the article

  • Java Counting # of occurrences of a word in a string

    - by Doug
    I have a large text file I am reading from and I need to find out how many times some words come up. For example, the word "the". I'm doing this line by line each line is a string. I need to make sure that I only count legit "the"'s the the in other would not count. This means I know I need to use regular expressions in some way. What I was trying so far is this: numSpace += line.split("[^a-z]the[^a-z]").length; I realize the regular expression may not be correct at the moment but I tried without that and just tried to find occurrences of the word the and I get wrong numbers to. I was under the impression this would split the string up into an array and how many times that array was split up was how many times the word is in the string. Any ideas I would be grateful.

    Read the article

  • What is the purpose of Finalization in java?

    - by Karthik
    Different websites are giving different opinions. My understanding is this: To clean up or reclaim the memory that an object occupies, the Garbage collector comes into action. (automatically is invoked???) The garbage collector then dereferences the object. Sometimes, there is no way for the garbage collector to access the object. Then finalize is invoked to do a final clean up processing after which the garbage collector can be invoked. is this right?

    Read the article

  • Garbage Collection Java

    - by simion
    On the slides i am revising from it says the following; Live objects can be identified either by maintaining a count of the number of references to each object, or by tracing chains of references from the roots. Reference counting is expensive – it needs action every time a reference changes and it doesn’t spot cyclical structures, but it can reclaim space incrementally. Tracing involves identifying live objects only when you need to reclaim space – moving the cost from general access to the time at which the GC runs, typically only when you are out of memory. I understand the principles of why reference counting is expensive but do not understand what "doesn’t spot cyclical structures, but it can reclaim space incrementally." means. Could anyone help me out a little bit please? Thanks

    Read the article

  • Java method: retrieve the inheriting type

    - by DrDro
    I have several classes that extend C and I would need a method that accepts any argument of type C. But in this method I would like to know if I'm dealing with A or B. * public A extends C public B extends C public void goForIt(C c)() If I cast how can I retrieve the type in a clean way (I just read using getClass or instanceof is often not the best way). *Sorry but I can't type closing braces

    Read the article

  • Building "isolated" and "automatically updated" caches (java.util.List) in Java.

    - by Aidos
    Hi Guys, I am trying to write a framework which contains a lot of short-lived caches created from a long-living cache. These short-lived caches need to be able to return their entier contents, which is a clone from the original long-living cache. Effectively what I am trying to build is a level of transaction isolation for the short-lived caches. The user should be able to modify the contents of the short-lived cache, but changes to the long-living cache should not be propogated through (there is also a case where the changes should be pushed through, depending on the Cache type). I will do my best to try and explain: master-cache contains: [A,B,C,D,E,F] temporary-cache created with state [A,B,C,D,E,F] 1) temporary-cache adds item G: [A,B,C,D,E,F] 2) temporary-cache removes item B: [A,C,D,E,F] master-cache contains: [A,B,C,D,E,F] 3) master-cache adds items [X,Y,Z]: [A,B,C,D,E,F,X,Y,Z] temporary-cache contains: [A,C,D,E,F] Things get even harder when the values in the items can change and shouldn't always be updated (so I can't even share the underlying object instances, I need to use clones). I have implemented the simple approach of just creating a new instance of the List using the standard Collection constructor on ArrayList, however when you get out to about 200,000 items the system just runs out of memory. I know the value of 200,000 is excessive to iterate, but I am trying to stress my code a bit. I had thought that it might be able to somehow "proxy" the list, so the temporary-cache uses the master-cache, and stores all of it's changes (effectively a Memento for the change), however that quickly becomes a nightmare when you want to iterate the temporary-cache, or retrieve an item at a specific index. Also given that I want some modifications to the contents of the list to come through (depending on the type of the temporary-cache, whether it is "auto-update" or not) and I get completly out of my depth. Any pointers to techniques or data-structures or just general concepts to try and research will be greatly appreciated. Cheers, Aidos

    Read the article

  • Java do while, while

    - by Pindatjuh
    Hello, what behaviour can I expect when I run this code: do while(testA) { // do stuff } while(testB); Will it behave like: do { while(testA) { // do stuff } } while(testB); Or: if(testA) { do { // do stuff } while(testA && testB); } Or something totally unexpected? I ask this question because I think this is quite ambiguous, and for other people searching on this topic, not because I am lazy to test it out.

    Read the article

  • Load/Store Objects in file in Java

    - by brain_damage
    I want to store an object from my class in file, and after that to be able to load the object from this file. But somewhere I am making a mistake(s) and cannot figure out where. May I receive some help? public class GameManagerSystem implements GameManager, Serializable { private static final long serialVersionUID = -5966618586666474164L; HashMap<Game, GameStatus> games; HashMap<Ticket, ArrayList<Object>> baggage; HashSet<Ticket> bookedTickets; Place place; public GameManagerSystem(Place place) { super(); this.games = new HashMap<Game, GameStatus>(); this.baggage = new HashMap<Ticket, ArrayList<Object>>(); this.bookedTickets = new HashSet<Ticket>(); this.place = place; } public static GameManager createManagerSystem(Game at) { return new GameManagerSystem(at); } public boolean store(File f) { try { FileOutputStream fos = new FileOutputStream(f); ObjectOutputStream oos = new ObjectOutputStream(fos); oos.writeObject(games); oos.writeObject(bookedTickets); oos.writeObject(baggage); oos.close(); fos.close(); } catch (IOException ex) { return false; } return true; } public boolean load(File f) { try { FileInputStream fis = new FileInputStream(f); ObjectInputStream ois = new ObjectInputStream(fis); this.games = (HashMap<Game,GameStatus>)ois.readObject(); this.bookedTickets = (HashSet<Ticket>)ois.readObject(); this.baggage = (HashMap<Ticket,ArrayList<Object>>)ois.readObject(); ois.close(); fis.close(); } catch (IOException e) { return false; } catch (ClassNotFoundException e) { return false; } return true; } . . . } public class JUnitDemo { GameManager manager; @Before public void setUp() { manager = GameManagerSystem.createManagerSystem(Place.ENG); } @Test public void testStore() { Game g = new Game(new Date(), Teams.LIONS, Teams.SHARKS); manager.registerGame(g); File file = new File("file.ser"); assertTrue(airport.store(file)); } }

    Read the article

  • Java document parsing over internet using POST

    - by Travis
    I've looked all around and decided to make my own library for accessing the EVE API. Requests are sent to a server address such as /account/Characters.xml.aspx. Characters.xml.aspx requires two item be submitted in POST and then it returns an XML file. So far I have this but it does not work, probably becuase I am using GET instead of POST: //Get the API data DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); DocumentBuilder builder = factory.newDocumentBuilder(); String url = "http://api.eveonline.com/account/Characters.xml.aspx?userID="+ userID+"?apiKey="+key; Document doc = builder.parse(url); How would I go about being able to parst an XML file that is generated by submitting variables in POST?

    Read the article

  • How to rotate an image properly in JPanel (Java)

    - by Bruce
    Hi guys, I'm working on rotating a loaded image. I set the graphics on a JPanel and then use standard AffineTransform in order to rotate it, say, 45 degrees. Unfortunately, the image is being cut, if it exceeds the panel area. How may I force JPanel to add scrolls to itself (while loading an image file, I would like to adjust the size of JPanel by adding the scrolls, without adjusting the size of JFrame). Or, in other words, how to correctly rotate the whole image? Thank you in advance for the reply!

    Read the article

  • Java data structure suggestion.

    - by techoverflow
    Hi folks, I am a newbie in this field so please excuse my silly mistakes :) So the issue I am facing is: On my webpage, I am displaying a table. For now my issue is concerned with three columns of the table. First is : Area Code Second is : Zone Code Third is: Value The relationship between these three is: 1 Area Code has 6 different Zone code's and all those 6 Zone codes have corresponding "Value" I need a data structer that would give me the flexibility to get a "Value" for a Zone code, which falls under a particular Area code. I have the same zone codes for all the Area codes: Zone codes are: 111, 222, 333, 444, 555, 666 After surfing your stackoverflow, I thought I can go with this structure: Map<Integer, Map<Integer, Double>> retailPrices = new HashMap<Integer, Map<Integer, Double>>(); Map<Integer, Double> codes = new HashMap<Integer, Double>(); where reatailPrices would hold an Area Code and a Map of Zone code as Key and "Value" as Value. but when I am trying to populate this through a SQL resultset, I am getting the following error: The method put(Integer, Map<Integer,Double>) in the type Map is not applicable for the arguments (Integer, Double) on line: `while(oResult.next()) retailPrices.put((new Integer(oResult.getString("AREA"))), (pegPlPrices.put(new Integer(oResult.getString("ZONE_CODE")), new Double(oResult.getString("VALUE"))))); }` please help me figure out this problem. Am I following the right approach?

    Read the article

  • java number exceeds long.max_value - how to detect?

    - by jurchiks
    I'm having problems detecting if a sum/multiplication of two numbers exceeds the maximum value of a long integer. Example code: long a = 2 * Long.MAX_VALUE; System.out.println("long.max * smth > long.max... or is it? a=" + a); This gives me -2, while I would expect it to throw a NumberFormatException... Is there a simple way of making this work? Because I have some code that does multiplications in nested IF blocks or additions in a loop and I would hate to add more IFs to each IF or inside the loop. Edit: oh well, it seems that this answer from another question is the most appropriate for what I need: http://stackoverflow.com/a/9057367/540394 I don't want to do boxing/unboxing as it adds unnecassary overhead, and this way is very short, which is a huge plus to me. I'll just write two short functions to do these checks and return the min or max long. Edit2: here's the function for limiting a long to its min/max value according to the answer I linked to above: /** * @param a : one of the two numbers added/multiplied * @param b : the other of the two numbers * @param c : the result of the addition/multiplication * @return the minimum or maximum value of a long integer if addition/multiplication of a and b is less than Long.MIN_VALUE or more than Long.MAX_VALUE */ public static long limitLong(long a, long b, long c) { return (((a > 0) && (b > 0) && (c <= 0)) ? Long.MAX_VALUE : (((a < 0) && (b < 0) && (c >= 0)) ? Long.MIN_VALUE : c)); } Tell me if you think this is wrong.

    Read the article

  • Social Media Java Design Problem

    - by jboyd
    I need to put something together quickly that will take blog posts and place them on social media sites, the requirements are as follows: Blog Entries are independent records that already exist, they have a published date and a modified date, the blog entry application cannot be changed, at least not substantially A new blog entry, or update needs to be sent to social media sites I currently do not need to update or delete social media communications if the blog entry is edited, or deleted, though I may need to later My design problems here are as follows: how do I know the status of each update how can I figure out what blog entry updates and postings have already been sent out? how can I quickly poll the blog entry table for postings that haven't yet been sent out? Avoiding looking at each Entry record from the DB as an object and asking if it's been sent already. That would be too slow. I cannot hook into any Blog Entry update code, my only option would be to create a trigger that an update queues something to be processed I'm looking for general guiding principles here, the biggest problem I'm having is coming up with any reasonable way to figure out if a blog entry should be sent to our social media sites in the first place

    Read the article

  • Ajax file uploading with java back end?

    - by Joren
    I don't want to use flash. I've found multiple jquery libraries that do this. Right now I'm using this one: http://demo.webdeveloperplus.com/ajax-file-upload/ The problem is they all use PHP. I tried just pointing it at my servlet instead of the PHP file, but it never gets called.

    Read the article

  • Java JPA @OneToMany neededs to reciprocate @ManyToOne?

    - by bguiz
    Create Table A ( ID varchar(8), Primary Key(ID) ); Create Table B ( ID varchar(8), A_ID varchar(8), Primary Key(ID), Foreign Key(A_ID) References A(ID) ); Given that I have created two tables using the SQL statements above, and I want to create Entity classes for them, for the class B, I have these member attributes: @Id @Column(name = "ID", nullable = false, length = 8) private String id; @JoinColumn(name = "A_ID", referencedColumnName = "ID", nullable = false) @ManyToOne(optional = false) private A AId; In class A, do I need to reciprocate the many-to-one relationship? @Id @Column(name = "ID", nullable = false, length = 8) private String id; @OneToMany(cascade = CascadeType.ALL, mappedBy = "AId") private List<B> BList; //<-- Is this attribute necessary? Is it a necessary or a good idea to have a reciprocal @OneToMany for the @ManyToOne? If I make the design decision to leave out the @OneToMany annotated attribute now, will come back to bite me further down.

    Read the article

  • Google App-Engine Java Batch Update

    - by Manjoor
    I need to upload a .csv file and save the records in bigtable. My application successfully parse 200 the records in the csv files and save to table. Here is my code to save the data. for (int i=0;i<lines.length -1;i++) //lines hold total records in csv file { String line = lines[i]; //The record have 3 columns integer,integer,Text if(line.length() > 15) { int n = line.indexOf(","); if (n>0) { int ID = lInteger.parseInt(ine.substring(0,n)); int n1 = line.indexOf(",", n + 2); if(n1 > n) { int Col1 = Integer.parseInt(line.substring(n + 1, n1)); String Col2 = line.substring(n1 + 1); myTable uu = new myTable(); uu.setId(ID); uu.setCol1(MobNo); Text t = new Text(Col2); uu.setCol2(t); PersistenceManager pm = PMF.get().getPersistenceManager(); pm.makePersistent(uu); pm.close(); } } } } But when no of records grow it gives timeout error. The csv file may have upto 800 records. Is it possible to do that in App-Engine? (something like batch update)

    Read the article

  • Communication via internet in Java

    - by Stuart
    What I mean is like servers on video games. You can run an application and it will set up a server on your computer with an IP and a port. For example, how would you make an application where one host application sets up a thing where it has an IP and a port, and another computer that has access to the internet as well can type in the IP and port and it would be able to communicate with the host? I mean simple communication, like sending a boolean or String. And would there be any security problems that would be needed to fix?

    Read the article

  • Profiling a Java Spring application

    - by niklassaers
    Hi guys, I have a Spring application that I believe has some bottlenecks, so I'd like to run it with a profiler to measure what functions take how much time. Any recommendations to how I should do that? I'm running STS, the project is a maven project, and I'm running Spring 3.0.1 Cheers Nik

    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 | 301 302 303 304 305 306 307 308 309 310 311 312  | Next Page >