Search Results

Search found 38453 results on 1539 pages for 'java card'.

Page 680/1539 | < Previous Page | 676 677 678 679 680 681 682 683 684 685 686 687  | Next Page >

  • Strings - Filling In Leading Zeros Wtih A Zero

    - by headscratch
    I'm reading an array of hard-coded strings of numeric characters - all positions are filled with a character, even for the leading zeros. Thus, can confidently parse it using substring(start, end) to convert to numeric. Example: "0123 0456 0789" However, a string coming from a database does not fill in the leading zero with a 'zero character', it simply fetches the '123 456 789', which is correct for an arithmetic number but not for my needs and makes for parsing trouble. Before writing conditionals to check for leading zeros and adding them to the string if needed, is there a simple way of specifying they be filled with a character ? I'm not finding this in my Java book... I could have done the three conditionals in the time it took to post this but, this is more about 'education'... Thanks

    Read the article

  • Do fields need to be explicitly final to have a "proper" immutable object?

    - by Yishai
    You often read about immutable objects requiring final fields to be immutable in Java. Is this in fact the case, or is it simply enough to have no public mutability and not actually mutate the state? For example, if you have an immutable object built by the builder pattern, you could do it by having the builder assign the individual fields as it builds, or having the builder hold the fields itself and ultimately return the immutable object by passing the values to its (private) constructor. Having the fields final has the obvious advantage of preventing implementation errors (such as allowing code to retain a reference to the builder and "building" the object multiple times while in fact mutating an existing object), but having the Builder store its data inside the object as it is built would seem to be DRYer. So the question is: Assuming the Builder does not leak the Object early and stops itself from modifying the object once built (say by setting its reference to the object as null) is there actually anything gained (such as improved thread safety) in the "immutability" of the object if the object's fields were made final instead?

    Read the article

  • Inferring type from method generics

    - by ng
    I am from a Java background and I am looking from the equivalent in c# for the following. public interface Reader { <T> T read(Class<? extends T> type); } Such that I can do the following, constraining the parameter and inferring the return type. Cat cat = reader.read(Cat.class); Dog dog = reader.read(Dog.class); I was hoping something like this would work in c# but I am not sure it will. public interface Reader { T Read<T>(); } And and do this. public class TypeReader : Reader { public T Read<T>() { Type type = T.GetType(); ... } } Is something like this even possible in c#?

    Read the article

  • Tomcat + Struts + OpenID raising ServletExceptions

    - by Rocjoe
    I am working with Tomcat 5.5.x with Struts 1.2 to run a rather large website (large w.r.t. source code). I'm looking to add OpenID to my website, mostly to access attribute exchange to help accelerate the registration process. Every Java implementation for OpenID I have attempted to use will cause a ServletException. Tracing this has been very difficult, but it seems merely instancing any class that makes use of Apache HttpClient will cause the crash. Is this a configuration problem I can address in the JVM, or is it positively wrong to try to initiate an outbound Http request from within an inbound Http request?

    Read the article

  • NullPointerException when accessing image files in a .jar file

    - by user548240
    Hi, I have pretty much tried everything but still have this same problem. I have the following setup: I have a images.jar containing a folder called 'images' in which there are multiple image files. I add images.jar to the java build path of the project in eclipse, and i've been trying to use the following code to access the individual images in the jar: URL url = this.getClass().getResource("images/a.png"); ImageIcon icon = new ImageIcon (url); Unfortunately, the URL object is always NULL. I don't think this has anything to do with where I put images.jar file as it is added to the classpath in eclipse. I have also tried using the path '/images/a.png', but still the same problem. Any suggestion would be extremely welcome! Thanks.

    Read the article

  • String as \x03\x00\x00\x00 to integer

    - by marta
    Helo: I have a question, that I solved in c, but now I want to do it in hava: I have a String like: '\x03\x00\x00\x00' This is representing an hexadecimal value of a integer. I transform to 0x03\0x00... And now I want to obtain the integer, but I don't know how to do it in java could someone give me some idea ? Thanks in advance (Is it some way to use this format ('\x03\x00\x00\x00' ) directly without use byte[] arrays? and in C can I use this format directly to build a integer (int)?)

    Read the article

  • Extendable accessing of sqlite database on android platform

    - by mscriven
    Hi, I am fairly new to the android sdk and databases and have been searching for an answer to this quite some time. I am trying to build an app which has multiple tables within a database. e.g. one for weapons, armours etc. However, my DatabaseManager class which handles all of my table creating, DatabaseHelper inner class and populating of data is creating for an extremely large class requiring high maintenance. Every time I would like to add or remove a table column I need to change quite a few areas of code, - Every reference to the addition of a row in that table with data - The method that the above calls - The method returning all of the database rows - The code in the helper class creating the table - Any specific update methods My question is this: Surely there must be some better way of coding this system, maybe using a database isn't the best way to go, or am i just not used to such large classes having only learned java at university and my largest class consisting of a mere 400-600 lines of code. Thanks for any help!

    Read the article

  • Hashing and salting values

    - by Avanst
    I am developing a small web app that internally authenticates users. Once the user is authenticated my web app then passes some information such as userID and Person's name to a third party web application. The third party developer is suggesting that we hash and salt the values. Forgive my ignorance, but what exactly does that mean? I am writing the app in Java. So what I am planning on doing is hashing the userID, Person's name, and some Math.random() value as the salt with Apache Commons Digest Utils SHA512 and passing that hashed string along with the userID and person's name. Is that the standard practice? I should be passing the third party the salt as well correct?

    Read the article

  • how to store a date, and then check to see if another date matches that date

    - by user797963
    I'm trying to figure out dates in Java and am completely lost. Do I use Date? Use epoch time? Gregorian Calendar? Let's say I have a want to store a date, then later compare it to other dates. For example, I've stored a date "10/27/2013". Then, I want to later compare it to dates entered later to see if a later date is identical to "10/27/2013", or if just the day, year, or month matches? What's the best way to do this?

    Read the article

  • Best way to access a sqlite database file in a web service.

    - by rogernorling
    First question from me on stack overflow. I have created a java web application containing a web service using netbeans (I hope a web application were the correct choice). I use the web application as is with no extra frameworks. This web service use a sqlite JDBC driver for accessing a sqlite database file. My problem is that the file path end up incorrect when I try to form the JDBC connection string. Also, the working directory is different when deploying and when running JUnit tests. I read somewhere about including the file as a resource, but examples of this were nowhere to be seen. In any case, what is the best way to open the sqlite database, both when the web service is deployed and when I test it "localy"? I don't know much about web services, I just need it to work, so please, help me with the technicalities.

    Read the article

  • How do you make long SQL invoked from other code readable?

    - by Artem
    This is a very open question, but I think it can be very beneficial for SQL readability. So you have a Java program, and you are trying to call a monster SQL statement from it, with many subqueries and joins. The starting point for my question is a string constant like this: static string MONSTER_STATEMENT = "SELECT " + " fields" + "WHERE "+ " fieldA = (SELECT a FROM TableC) " + "AND fieldB IN (%s)" + "AND fieldC = %d " + "FROM " " tableA INNER JOIN tableB ON ..."; It later gets filled using String.format and executed. What are you tricks for making this kind of stuff readable? Do you separate your inner joins. Do you indent the SQL itself inside the string? Where do you put the comments? Please share all of the tricks in your arsenal.

    Read the article

  • What is the most efficient way to pass data (list of pairs of [Integer + Double]) between two Google App Engine instances?

    - by ruslan
    What is the most efficient way to pass data (list of pairs of [Integer, Double]) between two Google App Engine instances ? Currently I use Java binary serialization. Frontend servlet receives data from the client in JSON format. I convert it to byte[] using ObjectOutput.writeObject and then send it to backend servlet via HTTP POST. It's not in production yet. Should I just pass client's JSON as it is to backend? It seems more logical. But it's bigger in size. Or should I use Google Protocol Buffers as stated in this benchmark article ? Thank you!!!

    Read the article

  • Mixing synchronized() with ReentrantLock.lock()

    - by yarvin
    In Java, do ReentrantLock.lock() and ReetrantLock.unlock() use the same locking mechanism as synchronized()? My guess is "No," but I'm hoping to be wrong. Example: Imagine that Thread 1 and Thread 2 both have access to: ReentrantLock lock = new ReentrantLock(); Thread 1 runs: synchronized (lock) { // blah } Thread 2 runs: lock.lock(); try { // blah } finally { lock.unlock(); } Assume Thread 1 reaches its part first, then Thread 2 before Thread 1 is finished: will Thread 2 wait for Thread 1 to leave the synchronized() block, or will it go ahead and run?

    Read the article

  • Eclipse bug? Switching on a null with only default case

    - by polygenelubricants
    I was experimenting with enum, and I found that the following compiles and runs fine on Eclipse (Build id: 20090920-1017, not sure exact compiler version): public class SwitchingOnAnull { enum X { ,; } public static void main(String[] args) { X x = null; switch(x) { default: System.out.println("Hello world!"); } } } When compiled and run with Eclipse, this prints "Hello world!" and exits normally. With the javac compiler, this throws a NullPointerException as expected. So is there a bug in Eclipse Java compiler?

    Read the article

  • how to achieve Inter-Widget communication

    - by bakore
    I was looking for a platform where widgets developed using various technologies like Java can communicate with each other. In other words When I add widgets to an interface I need them to talk to each other. For example A Click event in one widget should trigger an event in some other widget. I have been looking into the web for solutions and ways to do it, but couldnt find anything concrete. Any pointers or information on this would be great. Something like this http://blogs.sun.com/pdblog/entry/inter_widget_communication_in_cross

    Read the article

  • Can't get jQuery and IE to be friends

    - by Matthew
    Using jQuery and the Cycle plugin. Runs flawless in Safari, Chrome, Firefox, and the latest version of Opera. Won't run in older versions of Opera, and of course, IE. I know its running Java, because its picking up the rollovers. This is driving me batty. Hopefully its something simple. Here's the code... $(document).ready(function() { $("#slideshow").css("overflow", "hidden"); $("div#slides").cycle({ fx: 'scrollHorz', speed: 'slow', timeout: 0, prev: '#prev', next: '#next' }); Really appreciate the help guys.

    Read the article

  • Obtain distances to nearest landmarks (Mall, Hospital, and Airport etc.) using google map

    - by user227290
    I am working on a project in which I have around 100000 addreses in major cities in India(it is a table in a database). I want to know if it is possible to obtain the distances to to nearest landmarks (Mall, Hospital, and Airport etc.). Ideally I want these distances to be mergeed to the parent table. We have Java and Php coders to get it done once we find out how to go about it. Any pointers will be of great help. Thank you.

    Read the article

  • Generate service layer with Hibernate

    - by gmate
    Hi all! I generate *.hbm.xml mapping files and *.java file from the DB schema, with Hibernate tools. My question is, that is there any option, to generate service classes also? These are the classes where I implement the store(), find(), delete(), etc... methods. I know that for C# there are many solutions to generate almost everything. I'm looking for the same, but with Hibernate. Is there any? Thanks for every reply in advance!

    Read the article

  • Hibernate criterion Projection alias not being used

    - by sbzoom
    Do Hibernate Projection aliases even work? I could swear it just doesn't. At least, it doesn't do what I would expect it to do. Here is the java: return sessionFactory.getCurrentSession().createCriteria( PersonProgramActivity.class ).setProjection( Projections.projectionList().add( Projections.alias( Projections.sum( "numberOfPoints" ), "number_of_points" ) ).add( Projections.groupProperty( "person.id" ) ) ).setFirstResult( start ).setFetchSize( size ).addOrder( Order.desc( "numberOfPoints" ) ).list(); Here is the SQL that it generates: select sum(this_.number_of_points) as y0_, this_.person_id as y1_ from PERSON_PROGRAM_ACTIVITY this_ group by this_.person_id order by this_.number_of_points desc It doesn't seem to use the alias at all. I would think setting the alias would mean that "sum(this_.number_of_points)" would be aliased as "number_of_points" and not "y0_". Is there some trick I am missing? Thanks.

    Read the article

  • Integrate existing Spring based web application with a CMS

    - by anne_developer
    We have stable spring based (spring 2.x) web application. We have a new requirement which is our data entry operators should be able to login to some kind of an admin module and simply change the text in the web pages, change the color etc. I have seen PHP based CMS’s that allows authorized user to change the content in WYSIWYG manner. If anyone of you knows such open source Java CMS or third party application, which can facilitate such thing, please let me know. Please note: we cannot write our application from scratch. We are looking for pluggable component.

    Read the article

  • Waiting for ServerSocket accept() to put socket into "listen" mode

    - by inazaruk
    I need a simple client-server communication in order to implement unit-test. My steps: Create server thread Wait for server thread to put server socket into listen mode ( serverSocket.accept() ) Create client Make some request, verify responses Basically, I have a problem with step #2. I can't find a way to signal me when server socket is put to "listen" state. An asynchronous call to "accept" will do in this case, but java doesn't support this (it seems to support only asynchronous channels and those are incompatible with "accept()" method according to documentation). Of cause I can put a simple "sleep", but that is not really a solution for production code. So, to summarize, I need to detect when ServerSocket has been put into listen mode without using sleeps and/or polling.

    Read the article

  • Set intersection of two strings

    - by user1785712
    import java.util.*; class set { public static void main(String args[]) { TreeSet<Character> t1 = new TreeSet<Character>(); TreeSet<Character> t2 = new TreeSet<Character>(); String s1 = "Ambitab bachan"; String s2 = "Ranjikanth"; for(char c1:s1.toCharArray()) t1.add(c1); for(char c2:s2.toCharArray()) t2.add(c2); t2.retainAll(t1); System.out.println(t2); } } this program find the common character in two different string. in this program Treeset is used to store the value and retainAll() method is used to find the common characters. can anybody help me reduce the line of coding.thanks in advance

    Read the article

  • Retrieving images when database is in remote location...

    - by sasidhar
    Hi everyone, I am developing an application using java, my application would be accessed by number of different users simultaneously and the database resides in a central server. The access of the database from remote server is handled by just giving the appropriate IP of the server in the hibernate configure file. My question is, i have to store a picture regarding each user of the database, i heard that storing the image in the database and retrieving it from the database is not advised and has negative impact on the performance. Is it so ? What are the other possible ways i can implement this ? What is the best way to do it..? Please help....

    Read the article

  • How to switch data pins on/off on parallel port?

    - by Matt
    I want to simply switch certain data pins on and off, so that they can control a set of relays. I'm not asking about the hardware bit (should be easy), but I don't know where to begin writing the software. I don't want a high level library that can send bytes to a device - I literally want to switch on/off certain pins. I'm running Linux and I want to do this in Java, so would I just need a library? It would be nice if the library has good documentation and is easy to use, but if not then a short example code will help me get started.

    Read the article

  • How do I print the method body reflectively?

    - by kunjaan
    Right now I have private static void getMethods(Class<? extends Object> clazz) { Method[] declaredMethods = clazz.getDeclaredMethods(); for (Method aMethod : declaredMethods) { aMethod.setAccessible(true); // Print the declaration System.out.print(Modifier.toString(aMethod.getModifiers()) + " " + aMethod.getReturnType().getSimpleName() + " " + aMethod.getName()); // Get Parameter Types getParameters(aMethod); //Empty Body System.out.println("{}\n"); } } Which prints most information reflectively but creates an empty body. How do I add to the reflective nature of Java to print the method body?

    Read the article

< Previous Page | 676 677 678 679 680 681 682 683 684 685 686 687  | Next Page >