Search Results

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

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 774/1848 | < Previous Page | 770 771 772 773 774 775 776 777 778 779 780 781  | Next Page >

  • How to download attachment file from JSP

    - by Stardust
    I want to know how can I download any file from JSP page based on content disposition as an attachment from mail server. I want to create a link on JSP page, and by clicking on that link user can download file from mail server. The link should be for content dispostion's attachment type. How can I do that in JSP?

    Read the article

  • Why does appending "" to a String save memory?

    - by hsmit
    I used a variable with a lot of data in it, say String data. I wanted to use a small part of this string in the following way: this.smallpart = data.substring(12,18); After some hours of debugging (with a memory visualizer) I found out that the objects field smallpart remembered all the data from data, although it only contained the substring. When I changed the code into: this.smallpart = data.substring(12,18)+""; ..the problem was solved! Now my application uses very little memory now! How is that possible? Can anyone explain this? I think this.smallpart kept referencing towards data, but why? UPDATE: How can I clear the big String then? Will data = new String(data.substring(0,100)) do the thing?

    Read the article

  • Writing a Servlet that checks to see if JSP's exist and forwards to another JSP if they aren't

    - by Omar Kooheji
    I've beeb tasked with writing a servlet that intercepts a call to and JSP in a specific directoy, check that the file exists and if it does just forwarding to that file, if if doesn't I'm to forward to a default JSP. I've setup the web.xml as follows: <servlet> <description>This is the description of my J2EE component</description> <display-name>This is the display name of my J2EE component</display-name> <servlet-name>CustomJSPListener</servlet-name> <servlet-class> ... CustomJSPListener</servlet-class> <load-on-startup>1</load-on-startup> </servlet> ... <servlet-mapping> <servlet-name>CustomJSPListener</servlet-name> <url-pattern>/custom/*</url-pattern> </servlet-mapping> And the doGet method of the servlet is as follows: public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { logger.debug(String.format("Intercepted a request for an item in the custom directory [%s]",request.getRequestURL().toString())); String requestUri = request.getRequestURI(); // Check that the file name contains a text string if (requestUri.toLowerCase(Locale.UK).contains("someText")){ logger.debug(String.format("We are interested in this file [%s]",requestUri)); File file = new File(requestUri); boolean fileExists = file.exists(); logger.debug(String.format("Checking to see if file [%s] exists [%s].",requestUri,fileExists)); // if the file exists just forward it to the file if (fileExists){ getServletConfig().getServletContext().getRequestDispatcher( requestUri).forward(request,response); } else { // Otherwise redirect to default.jsp getServletConfig().getServletContext().getRequestDispatcher( "/custom/default.jsp").forward(request,response); } } else { // We aren't responsible for checking this file exists just pass it on to the requeseted jsp getServletConfig().getServletContext().getRequestDispatcher( requestUri).forward(request,response); } } This seems to result in an error 500 from tomcat, I think this is because the servlet is redirecting to the same folder which is then being intercepted again by the servlet, resulting in an infinite loop. Is there a better way to do this? I'm lead to believe that I could use filters to do this, but I don't know very much about them.

    Read the article

  • Problem of instanceOf

    - by eric2323223
    Hi, could anyone tell me why this code won't compile? public boolean isOf(Class clazz, Object obj){ if(obj instanceof clazz){ return true; }else{ return false; } } Why I can't pass a class variable to instanceOf? Thanks in advance.

    Read the article

  • hibernate column uniqueness question

    - by Seth
    I'm still in the process of learning hibernate/hql and I have a question that's half best practices question/half sanity check. Let's say I have a class A: @Entity public class A { @Id @GeneratedValue(strategy=GenerationType.AUTO) private Long id; @Column(unique=true) private String name = ""; //getters, setters, etc. omitted for brevity } I want to enforce that every instance of A that gets saved has a unique name (hence the @Column annotation), but I also want to be able to handle the case where there's already an A instance saved that has that name. I see two ways of doing this: 1) I can catch the org.hibernate.exception.ConstraintViolationException that could be thrown during the session.saveOrUpdate() call and try to handle it. 2) I can query for existing instances of A that already have that name in the DAO before calling session.saveOrUpdate(). Right now I'm leaning towards approach 2, because in approach 1 I don't know how to programmatically figure out which constraint was violated (there are a couple of other unique members in A). Right now my DAO.save() code looks roughly like this: public void save(A a) throws DataAccessException, NonUniqueNameException { Session session = sessionFactory.getCurrentSession(); try { session.beginTransaction(); Query query = null; //if id isn't null, make sure we don't count this object as a duplicate if(obj.getId() == null) { query = session.createQuery("select count(a) from A a where a.name = :name").setParameter("name", obj.getName()); } else { query = session.createQuery("select count(a) from A a where a.name = :name " + "and a.id != :id").setParameter("name", obj.getName()).setParameter("name", obj.getName()); } Long numNameDuplicates = (Long)query.uniqueResult(); if(numNameDuplicates > 0) throw new NonUniqueNameException(); session.saveOrUpdate(a); session.getTransaction().commit(); } catch(RuntimeException e) { session.getTransaction().rollback(); throw new DataAccessException(e); //my own class } } Am I going about this in the right way? Can hibernate tell me programmatically (i.e. not as an error string) which value is violating the uniqueness constraint? By separating the query from the commit, am I inviting thread-safety errors, or am I safe? How is this usually done? Thanks!

    Read the article

  • How can I load file into web app through certain periods?

    - by Elena
    Hi all! I have next task: I need to load the same file into my web app several times, for example - twice a day! Suppose in that file I have information, that changes, and I need to load this info into my app to change the statistics for example. How can I load file several times (twice an hour, or twice a day)? What should I use? Is any algorithm to do that? I am not allowed to use external libraries like Quartz Scheduler. So I need to do it with Thread and/or Timer. Can anybody give me some example or algorithm how to do it. Where can I create the entry point to my Thread, can I do it in managed bean or I need some sort of filter/listener/servlet. I works with jsf and richFaces. Maybe in this technologies there are some algorithms to solve my problem. Any ideas? Thanks very much for help!

    Read the article

  • best way to pick a random subset from a collection?

    - by Tom
    I have a set of objects in a Vector from which I'd like to select a random subset (e.g. 100 items coming back; pick 5 randomly). In my first (very hasty) pass I did an extremely simple and perhaps overly clever solution: Vector itemsVector = getItems(); Collections.shuffle(itemsVector); itemsVector.setSize(5); While this has the advantage of being nice and simple, I suspect it's not going to scale very well, i.e. Collections.shuffle() must be O(n) at least. My less clever alternative is Vector itemsVector = getItems(); Random rand = new Random(System.currentTimeMillis()); // would make this static to the class List subsetList = new ArrayList(5); for (int i = 0; i < 5; i++) { // be sure to use Vector.remove() or you may get the same item twice subsetList.add(itemsVector.remove(rand.nextInt(itemsVector.size()))); } Any suggestions on better ways to draw out a random subset from a Collection?

    Read the article

  • request parameter is taking null value in servlets

    - by Dusk
    Hi, I want to know how can I get the value of the request parameters "j_username" and "j_password"? After successfully login using form based authentication, I want my servlet to get the value of parameters "j_username" and "j_password", but I'm getting null as the value in both parameters. Could anyone please tell me how can I get the actual value of both paramters? Servlets class : package foo; import javax.servlet.http.*; import javax.servlet.*; public class RequestHandler extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) { try { String user = request.getParameter("j_username"); String password = request.getParameter("j_password"); response.getWriter().println(user+" "+password); } catch(Exception e) { e.printStackTrace(); } } } output: null null

    Read the article

  • SLF4J, Common Logging, console output

    - by Mauricio Scheffer
    I have this 3rd party library that has: slf4j-api-1.5.5.jar slf4j-jdk14-1.5.5.jar jcl-over-slf4j-1.5.5.jar I want to write some tests against this library and see its log output, and I don't want to add any more logging libraries (no log4j or anything else). I understand that SLF4J and Common Logging are both logging abstractions so I probably need to write my own simple concrete logger (or maybe not, since jcl-over-slf4j includes org.apache.commons.logging.impl.SimpleLog?). If so, what interfaces should I implement, and more importantly, how do I set up SL4J/Common Logging to use my logger in my test? I read in the SLF4J docs that I have to modify the StaticLoggerBinder class... does that really mean that I actually have to download SLF4J sources, modify the class and recompile it?

    Read the article

  • Turning off hibernate logging console output

    - by Jared
    I'm using hibernate 3 and want to stop it from dumping all the startup messages to the console. I tried commenting out the stdout lines in log4j.properties but no luck. I've pasted my log file below. Also I'm using eclipse with the standard project structure and have a copy of log4j.properties in both the root of the project folder and the bin folder. ### direct log messages to stdout ### #log4j.appender.stdout=org.apache.log4j.ConsoleAppender #log4j.appender.stdout.Target=System.out #log4j.appender.stdout.layout=org.apache.log4j.PatternLayout #log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n ### direct messages to file hibernate.log ### log4j.appender.file=org.apache.log4j.FileAppender log4j.appender.file.File=hibernate.log log4j.appender.file.layout=org.apache.log4j.PatternLayout log4j.appender.file.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n ### set log levels - for more verbose logging change 'info' to 'debug' ### log4j.rootLogger=warn, stdout #log4j.logger.org.hibernate=info log4j.logger.org.hibernate=debug ### log HQL query parser activity #log4j.logger.org.hibernate.hql.ast.AST=debug ### log just the SQL #log4j.logger.org.hibernate.SQL=debug ### log JDBC bind parameters ### log4j.logger.org.hibernate.type=info #log4j.logger.org.hibernate.type=debug ### log schema export/update ### log4j.logger.org.hibernate.tool.hbm2ddl=debug ### log HQL parse trees #log4j.logger.org.hibernate.hql=debug ### log cache activity ### #log4j.logger.org.hibernate.cache=debug ### log transaction activity #log4j.logger.org.hibernate.transaction=debug ### log JDBC resource acquisition #log4j.logger.org.hibernate.jdbc=debug ### enable the following line if you want to track down connection ### ### leakages when using DriverManagerConnectionProvider ### #log4j.logger.org.hibernate.connection.DriverManagerConnectionProvider=trac5

    Read the article

  • Generating equals / hashcode / toString using annotation

    - by Bruno Bieth
    I believe I read somewhere people generating equals / hashcode / toString methods during compile time (using APT) by identifying which fields should be part of the hash / equality test. I couldn't find anything like that on the web (I might have dreamed it ?) ... That could be done like that : public class Person { @Id @GeneratedValue private Integer id; @Identity private String firstName, lastName; @Identity private Date dateOfBirth; //... } For an entity (so we want to exlude some fields, like the id). Or like a scala case class i.e a value object : @ValueObject public class Color { private int red, green, blue; } Not only the file becomes more readable and easier to write, but it also helps ensuring that all the attributes are part of the equals / hashcode (in case you add another attribute later on, without updating the methods accordingly). I heard APT isn't very well supported in IDE but I wouldn't see that as a major issue. After all, tests are mainly run by continuous integration servers. Any idea if this has been done already and if not why ? Thanks

    Read the article

  • alternatedocroot

    - by ring bearer
    Using Sun Glassfish Enterprise server v2.1.1 I am using "alternatedocroot" via sun-web.xml for my web application to abstract out static content from actual deploy-able code (EAR/WAR) What I have is a cluster of two server instances distributed across two physical hosts - HOST1 and HOST2. "alternatedocroot" points to /data/static-content/ on both HOST1 and HOST2. Would DAS (Domain application server )take care of syncing /data/static-content between HOST1 and HOST2 if I use syncinstances=true option while starting up the cluster? Thanks!

    Read the article

  • how to convert byte array to key format??

    - by sebby_zml
    hi everyone, i would like to know how to convert byte array into key. i am doing an AES encryption/decryption. instead of generating a key, i would like to use my generated byte array. byte[] clientCK = Milenage.f3(sharedSecret16, RANDbytes, opc); let say i have a byte array called clientCK, stated above. i want to use it in AES encryption as shown below. Cipher c = Cipher.getInstance("AES"); c.init(Cipher.ENCRYPT_MODE, key); byte[] encValue = c.doFinal(valueToEnc.getBytes()); String encryptedValue = new BASE64Encoder().encode(encValue); therefore, i need to convert that byte array clientCK into key format. please help.

    Read the article

  • Repackaging Jasper-Reports into an application specific OSGi bundle, legal or not?

    - by Chris
    Hi, I wanted to ask (probably a silly) question regarding the packaging of existing open-source components as OSGi bundles (more specifically Jasper Reports). I have an application that I am converting from a monolithic jar-hell type architecture to something more moduler and OSGi is my weapon of choice. There are various modules I have in mind but one of the modules is a reporting module. My own reporting module will be a jar file containing my code that should reference a Jasper Reports bundle. Trouble is, Jasper reports depends on far far too many libraries and is quite monolithic in its own right. I therefore wish to build my own Jasper Reports bundle but this is where I start getting confused about the legality of repackaging. I don't plan to re-compile but I do plan to re-bundle removing known items that I do not require. Can anyone offer advice on whether I am permitted to repackage (not recompile or extend) open-source libraries into OSGi bundles without falling foul of 'derivative works' clause of LGPL? I noticed that Groovy seems to offer some monolithic jars that include all dependancies and actually goes so far as to re-arrange the packages of its dependancies so that there are no namespace conflicts. This seems to me to be a violation of the license but if anyone can reassure me that this is legal then I would feel safer about my less intrusive custom-bundling of Jasper reports. Thanks for your time, Chris

    Read the article

  • Creating GUI for Bantumi game

    - by owca
    I've written backend for simple Bantumi game. Now I'd like to create a simple GUI for it, so that it would look like this : How to start ? What layout should I use, and what type of component each element should be? Classes : Basket Player Game Main Shared

    Read the article

  • How to increase detail band height dynamically

    - by Chandu
    Hi All, I am using ireport. My requirement is to increase the detail band height dynamically when the text field has more data , are there any settings to increase to it? I am using one textfield in the detail band when it has more information(words), it is displaying only some information.i.e the words are being cut off. Depending on the detail band height the words are displaying.I would like to increase the band hieght dynamically when the text field has more data. Please advice me on this regard. Regards, Chandu

    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 | 770 771 772 773 774 775 776 777 778 779 780 781  | Next Page >