Search Results

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

Page 980/1848 | < Previous Page | 976 977 978 979 980 981 982 983 984 985 986 987  | Next Page >

  • Null Pointer Exception

    - by user1507835
    I am getting a null pointer exception, but I dont know why. I checked to see if the cell was null before I read it to a string. So, why is that string null? private void fillArray() private void fillArray() { try { readBook = new HSSFWorkbook(readFile); } catch (IOException e) { System.out .println("If we know what we're doing, no one should ever see this line."); } if (readBook != null) {HSSFSheet infoSheet = readBook.getSheetAt(0); HSSFRow headingsRow = infoSheet.getRow(0); int i = 0; HSSFCell cell = headingsRow.getCell(i); String columnHeading = cell.toString(); while (cell != null && !(cell.toString().equals(""))) { cell = headingsRow.getCell(i); columnHeading = cell.toString(); columnHeadings.add(columnHeading); i++; } if(columnListIsSetup == false) { createList(); columnListIsSetup = true; } }

    Read the article

  • How to move positions within an array?

    - by Jade Mulholland
    A program that simply moves array elements. Two variables: userInputVariable and blankSpaceVariable. I have a 2D array named table. Defined as table[userInputVariable + 1][6] I am printing out this array in a table format, and the far left column is numbered by whatever number the user entered at the beginning of the program. I then ask the user where they would like to enter a blank space within the array. This blank space acts like a divider for all the other information in the array. For example, if the user enters 10 at the start for the userInputVariable, and then enters 5 for the blank space. Once printed, the numbers should go like this: 1, 2, 3, 4, --, 5, 6, 7, 8, 9, 10. My plan has been to create a for loop and try to move all the numbers in the array back a position starting from the blank space variable. What I currently have, but does not work: for (int i = blankSpaceVariable; i < table.length - 1; i++) { table[i] = table[i + 1]; } table[blankSpaceVariable] = "--"; With my current code, the numbers go like this: 1, 2, 3, 4, 6, 7, 8, 9, 10 Tried completing this a few different ways also, but the other info within my 2D array didn't move with the numbers. So I thought that this approach can hopefully move all the info within my 2D array down, and make way for a blank section. All help is greatly appreciated!

    Read the article

  • from Hibernate hbm to JPA annotations, a challenging one

    - by nodje
    Hi, I've been struggling with this one for quite some time already. It appears a lot less simple than I thought it'd be: This is included in the "COTISATION" table mapping an uses SynchroDataType, extending Hibernate UserType. This works really great, and I can't find a way to translate it to proper JPA, while keeping the convenience of it. Does someone has a solution for that kind of one-to-one mapping? cheers

    Read the article

  • @ExceptionHandler doesn't handle the thrown exceptions

    - by Javi
    Hello, I have a method in my controller which will handle the exceptions thrown by the application. So I have a method like this one. @Controller public class ExceptionController { @RequestMapping(value="/error") @ExceptionHandler(value={Exception.class, NullPointerException.class}) public String showError(Exception e, Model model){ return "tiles:error"; } } And to try I if it works I throw a NullPointerException in another method in other method controller: boolean a = true; if(a){ throw new NullPointerException(); } After the exception is thrown it is printed in the JSP, but it doesn't go throw my showError() method (I've set a breakpoint there and it never enters). showError() method will catch the exception and will show different error pages depending on the exception type (though now it always shows the same error page). If I go to the url /error it shows the error page so the showError() method is OK. I'm using Spring 3. What can be the problem? Thanks.

    Read the article

  • Q about AbstractApplicationContext.getBeansOfType() and getBean()

    - by Paul Reiners
    We have the following legacy 2.0.7 Spring code: final Map<String, MyClass> secondaryFactories = (Map<String, MyClass>) context.getBeansOfType(MyClass.class, false, true); return (MyClass) context.getBean("myClass"); where context is an instance of org.springframework.context.support.AbstractApplicationContext Note that we ignore the return value of getBeansOfType(). This works just fine, but the problem is that the call to getBeansOfType() is time-consuming. However, even though we ignore the return value of this call, if we try to eliminate this call, then the instance of MyClass returned by getBean() is not fully initialized. (So, apparently, the call to getBeansOfType() is having some sort of side-effects that we need.) We suspect that the call to getBeansOfType() is overkill and we could do something more lightweight so that the instance of MyClass obtained by the call to getBean() would be fully initialized (but it's not null and no exception is thrown). So, is there a more efficient way of doing this?

    Read the article

  • Logger.setLevel() doesn't enable logging correctly

    - by ripper234
    Situation: I have this log4j logger: private static final Logger logger = Logger.getLogger(ThisClassName.class); And am trying to set it programatically through: Logger.getLogger(ThisClassName.class).setLevel(Level.DEBUG); Still, DEBUG level prints are swalloed (while INFO prints are printed successfully). Even this bit has no effect: Logger.getRootLogger().setLevel(Level.DEBUG); Calling logger.debug("foo") reaches Category.forcedLog() and ConsoleAppender.doAppend(), and then fails (quits) at: if(!isAsSevereAsThreshold(event.getLevel())) Any idea why this is happening?

    Read the article

  • Redirects in Glassfish (adding trailing slash)

    - by echox
    Is it possible to add a trailing slash to the default context of an application? Example: http://www.uri.com/foo -> http://www.uri.com/foo/ I added the following redirect to the server properties: redirect_1: from=/foo url-prefix=/foo/ and this ends up in a loop... Several other configurations also didn't work :-/ I'm using glassfish v2.1-b60e.

    Read the article

  • Which is the 'correct' way to do this (if statement)

    - by frinkz
    I've got plenty of these lying around, and I'm wondering if I'm going to face any trouble - or performance problems. I have method A: MyClass monkey; ... if(monkey != null) { ... } Or method B: boolean hasMonkey; //This is set to TRUE when monkey is not null MyClass monkey; ... if(hasMonkey) { ... } On a functional level, they both do the same thing. Right now, I'm using method A. Is that a bad way of doing things? Which is going to perform better?

    Read the article

  • Ques: Which method will be called and y?

    - by Gaurav
    Ques: Which method will be called and y? public class Test { public void method(Object o){ System.out.println("object"); } public void method(String s) { System.out.println("String"); } public void method() { System.out.println("blank"); } /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Test test=new Test(); test.method(null); } }

    Read the article

  • Creating an instance within the Class itself

    - by didxga
    What's going on when the assignment statement executed at Line 4, does compiler ignore the new operator and keep the foo variable being null or something else happen to handle this awkward moment? public class Foo { // creating an instance before its constructor has been invoked, suppose the "initializing" // gets printed in constructor as a result of the next line, of course it will not print it private Foo foo = new Foo();//Line 4 public Foo() { System.out.println("initializing"); } }

    Read the article

  • Why the generated key size is not constant?

    - by Tom Brito
    The following code prints randomly 634, 635, 636, each time I run it. Why its not constant? public static void main(String[] args) throws Exception { KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("RSA", "BC"); keyPairGen.initialize(1024); RsaKeyPair keyPair = new RsaKeyPair(keyPairGen.generateKeyPair()); System.out.println(keyPair.getPrivate().getEncoded().length); }

    Read the article

  • JPA 2.0 Provider Hibernate Spring MVC 3.0

    - by user558019
    Dear All i have very strange problem we are using jpa 2.0 with hibernate and spring 3.0 mvc annotations based Database generated through JPA DDL is true and MySQL as Database; i will provide some refference classes and then my porblem. public abstract class Common implements serializable{ @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name = "id", updatable = false) private Long id; @ManyToOne @JoinColumn private Address address; //with all getter and setters //as well equal and hashCode } public class Parent extends Common{ private String name; @OneToMany(cascade = {CascadeType.MERGE,CascadeType.PERSIST}, mappedBy = "parent") private List<Child> child; //setters and rest of class } public class child extends Common{ //some properties with getter/setters } public class Address implements Serializable{ @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name = "id", updatable = false) private Long id; private String street; //rest of class with get/setter } as in code you can see that parents and child classes extends Common class so both have address property and id , the problem occurs when change the address refference in parent class it reflect same change in all child objects in list and if change address refference in child class then on merge it will change address refference of parent as well i am not able to figure out is it is problem of jpa or hibernate or spring thanks in advance

    Read the article

  • Background image JFrame with content

    - by Petr Safar
    I have a JFrame with BorderLayout, there are panels on all sides (North, East ,...). In the panels there are labels and buttons mostly. Now I want the frame to have a background image, some research told me that i had to change the content pane of my frame. When I try this however, the content gets put in the background and isn't visible. Also, I don't know how to resize the image if the frame is resized. Is there an easy fix for this or will I have to rework most of my code?

    Read the article

  • Speed of Synchronization vs Normal

    - by Swaranga Sarma
    I have a class which is written for a single thread with no methods being synchronized. class MyClass implements MyInterface{ //interface implementation methods, not synchronized } But we also needed a synchronized version of the class. So we made a wrapper class that implements the same interface but has a constructor that takes an instance of MyClass. Any call to the methods of the synchronized class are delegated to the instance of MyClass. Here is my synchronized class.. class SynchronizedMyClass implements MyInterface{ //the constructor public SynchronizedMyClass(MyInterface i/*this is actually an instance of MyClass*/) //interface implementation methods; all synchronized; all delegated to the MyInterface instance } After all this I ran numerous amounts of test runs with both the classes. The tests involve reading log files and counting URLs in each line. The problem is that the synchronized version of the class is consistently taking less time for the parsing. I am using only one thread for the teste, so there is no chance of deadlocks, race around condition etc etc. Each log file contains more than 5 million lines which means calling the methods more than 5 million times. Can anyone explain why synchronized versiuon of the class migt be taking less time than the normal one?

    Read the article

  • How do I specify the foreign key on a many-to-one relationship when is not a property on the object

    - by jjujuma
    I'm trying to map a many-to-one relationship from MarketMenuBranch to Market. My classes look like: public class Market implements Serializable { private int id; private String name; private List<MarketMenuBranch> marketMenuBranches; // accessors / mutators etc... public class MarketMenuBranch implements Serializable { private MarketMenuBranchId id; private String name; // accessors / mutators etc... public class MarketMenuBranchId implements Serializable { private int marketId; private int sequence; // accessors / mutators etc... But I don't know what I can put for the property name (where I have ???? below). I really want to put id.marketId but that seems to be wrong. <class name="MarketMenuBranch" table="MARKET_MENU_BRANCH"> <composite-id name="id" class="MarketMenuBranchId"> <key-property name="marketId"/> <key-property name="sequence"/> </composite-id> <property name="name"/> <many-to-one name="????????"/> </class> How can I do this?

    Read the article

  • Unusual "static" method declaration

    - by Jason
    public class Card { public enum Rank { DEUCE, THREE, FOUR, FIVE, SIX, SEVEN, EIGHT, NINE, TEN, JACK, QUEEN, KING, ACE } public enum Suit { CLUBS, DIAMONDS, HEARTS, SPADES } private final Rank rank; private final Suit suit; private Card(Rank rank, Suit suit) { this.rank = rank; this.suit = suit; } public Rank rank() { return rank; } public Suit suit() { return suit; } public String toString() { return rank + " of " + suit; } private static final List<Card> protoDeck = new ArrayList<Card>(); // Initialize prototype deck **static** { for (Suit suit : Suit.values()) for (Rank rank : Rank.values()) protoDeck.add(new Card(rank, suit)); } public static ArrayList<Card> newDeck() { return new ArrayList<Card>(protoDeck); // Return copy of prototype deck } } I have a quick question. The code block that starts right after the static keyword declaration, what type of method is that ? I haven't ever seen that before. If anyone could enlighten me, that would be greatly appreciated. Thanks.

    Read the article

  • Swing: Programmatically select a text

    - by HH
    Hey everyone, I have a very simple Swing GUI with just a JTetxtArea. I am trying to programmatically select a part of text using: textArea.select(startSelection,endSelection); This work. However as soon as I add some other components to the GUI I do not see selection anymore frame.getContentPane().add(button); frame.getContentPane().add(textArea); textArea.select(startSelection,endSelection); I suspect that during layouting the gui, some event causes the text to be deselected. Am I right? And could anybody suggest a solution? My goal is to have a program which displays a text, and allows the user to input start and end selection position, and a selection appears between these two position. Thank you.

    Read the article

  • Hibernate query cache automatically refreshed on external update?

    - by artgon
    I'm creating a service that has read-only access to the database. I have a query cache and a second level cache enabled (READ_ONLY mode) in Hibernate to speed up the service, as the tables being accessed change rarely. My question is, if someone goes into the DB and changes the tables manually (i.e. outside of Hibernate), does the cache recognize automatically that it needs to be cleared? Is there a time limit on the cache?

    Read the article

  • How can you remove a Criterion from a criteria?

    - by ChuckM
    Hello, For instance if I do something like: Criteria c = session.createCriteria(Book.class) .add(Expression.ge("release",reDate); .add(Expression.ge("price",price); .addOrder( Order.asc("date") ) .setFirstResult(0) .setMaxResults(10); c.list(); How can I use the same criteria instance, but remove (for example) the second criterion? I'm trying to build a dynamic query in which I'd like to let the user remove a filter, without the backend having to reconstruct the criteria from scratch. Thank you

    Read the article

< Previous Page | 976 977 978 979 980 981 982 983 984 985 986 987  | Next Page >