Search Results

Search found 33603 results on 1345 pages for 'java champion stephen chin'.

Page 643/1345 | < Previous Page | 639 640 641 642 643 644 645 646 647 648 649 650  | Next Page >

• Handling 'session expired' in JSF web application, running in JBoss AS 5

  - by Veera

  This question is related to my other question "How to redirect to Login page when Session is expired in Java web application?". Below is what I'm trying to do: I've a JSF web application running on JBoss AS 5 When the user is inactive for, say 15 minutes, I need to log out the user and redirect him to the login page, if he is trying to use the application after the session has expired. So, as suggested in 'JSF Logout and Redirect', I've implemented a filter which checks for the session expired condition and redirects the user to a session-timed-out.jsp page, if the session has expired. I've added SessionExpiryCheckFilter on top of all other filter definitions in web.xml, so that my session expiry check will get the first hit always. Now comes the challenge I'm facing. Since I'm using JBoss AS, when the session expired, JBoss automatically redirects me to the login page (note that the session expiry check filter is not invoked). So, after I log-in, my SessionExpiryCheckFilter intercepts the request, and it sees a session is available. But, it throws the exception javax.faces.application.ViewExpiredException: viewId:/mypage.faces - View /mypage.faces could not be restored. Have anyone faced this issue before? Any ideas to solve this issue?

  Read the article

• How can I place validating constraints on my method input parameters?

  - by rcampbell

  Here is the typical way of accomplishing this goal: public void myContractualMethod(final String x, final Set<String> y) { if ((x == null) || (x.isEmpty())) { throw new IllegalArgumentException("x cannot be null or empty"); } if (y == null) { throw new IllegalArgumentException("y cannot be null"); } // Now I can actually start writing purposeful // code to accomplish the goal of this method I think this solution is ugly. Your methods quickly fill up with boilerplate code checking the valid input parameters contract, obscuring the heart of the method. Here's what I'd like to have: public void myContractualMethod(@NotNull @NotEmpty final String x, @NotNull final Set<String> y) { // Now I have a clean method body that isn't obscured by // contract checking If those annotations look like JSR 303/Bean Validation Spec, it's because I borrowed them. Unfortunitely they don't seem to work this way; they are intended for annotating instance variables, then running the object through a validator. Which of the many Java design-by-contract frameworks provide the closest functionality to my "like to have" example? The exceptions that get thrown should be runtime exceptions (like IllegalArgumentExceptions) so encapsulation isn't broken.

  Read the article

• Elegantly handling constraint violations in EJB/JPA environment?

  - by hallidave

  I'm working with EJB and JPA on a Glassfish v3 app server. I have an Entity class where I'm forcing one of the fields to be unique with a @Column annotation. @Entity public class MyEntity implements Serializable { private String uniqueName; public MyEntity() { } @Column(unique = true, nullable = false) public String getUniqueName() { return uniqueName; } public void setUniqueName(String uniqueName) { this.uniqueName = uniqueName; } } When I try to persist an object with this field set to a non-unique value I get an exception (as expected) when the transaction managed by the EJB container commits. I have two problems I'd like to solve: 1) The exception I get is the unhelpful "javax.ejb.EJBException: Transaction aborted". If I recursively call getCause() enough times, I eventually reach the more useful "java.sql.SQLIntegrityConstraintViolationException", but this exception is part of the EclipseLink implementation and I'm not really comfortable relying on it's existence. Is there a better way to get detailed error information with JPA? 2) The EJB container insists on logging this error even though I catch it and handle it. Is there a better way to handle this error which will stop Glassfish from cluttering up my logs with useless exception information? Thanks.

  Read the article

• RemoteRef.invoke implementation

  - by phill

  Just finished a basic implementation of RMI for a class project, and now I am interested in how it is actually done. Sun is kind enough to provide the source for the majority of the Java classes with the JDK, however an implementation of RemoteRef doesn't seem to be there. I have the source for the interface RemoteRef along with the ServerRef interface and one implementation, ProxyRef, which just calls invoke on another RemoteRef, but none of the classes that implement actual code, ActivatableRef or UnicastRef for example, are included. I mention ActivatableRef and UnicastRef because I believe these have proper implementations of invoke thanks to the wonder that is Eclipse and its class file editor showing that it is more then just a method declaration. Although I can tell that it is more then a declaration, I can't get much more out of it, building a string here, throw exception there, but nothing about the process that is taking place to send the remote method call. Would anyone here happen to know where I can get this code, or if its even available? If it is not available, would anyone happen to know what the message being sent to the server looks like? phill

  Read the article

• ExecutorService - scaling

  - by Stanciu Alexandru-Marian

  I am trying to write a program in Java using ExecutorService and it's function invokeAll. My question is: does the invokeAll functions solve the tasks simultaneously? I mean, if i have two processors, there will be two workers in the same time? Because a can't make it to scale correct. It takes the same time to complete the problem if i give newFixedThreadPool(2) or 1. List<Future<PartialSolution>> list = new ArrayList<Future<PartialSolution>>(); Collection<Callable<PartialSolution>> tasks = new ArrayList<Callable<PartialSolution>>(); for(PartialSolution ps : wp) { tasks.add(new Map(ps, keyWords)); } list = executor.invokeAll(tasks); Map is a class that implements Callable and wp is a vector of Partial Solutions, a class that holds some informations in different times. Why doesn't it scale? What could be the problem? Thank you, Alex

  Read the article

• Selenium and Firefox 9's "Will you help improve Mozilla Firefox" popup

  - by Rup

  I'm trying to test a Java web app using Selenium 2.16.1. When Selenium opens Firefox, I see a band at the top of the page with message "Will you help improve Mozilla Firefox" For some reason this breaks selenium.click("id=submit"); selenium.waitForPageToLoad("60000"); which is trying to log in - it becomes a no-op, and the test fails because it's then expecting to have logged in. If I break on the click line and clear the 'will you help' band before continuing then the form submit succeeds. Is there a way to suppress this band from appearing? (I expect that would mean setting a property in Firefox's default profile - where do I find that?) Or is there a way to get Selenium to spot and dismiss this first? Thanks! I'm using Firefox 9.0.1. Solved - thanks Danny! Just in case it isn't clear from the answers and comments below: This was an issue with 2.16.1 and IMO the best solution is to upgrade to 2.17 or later.

  Read the article

• Problem with JMX query of Coherence node MBeans visible in JConsole

  - by Quinn Taylor

  I'm using JMX to build a custom tool for monitoring remote Coherence clusters at work. I'm able to connect just fine and query MBeans directly, and I've acquired nearly all the information I need. However, I've run into a snag when trying to query MBeans for specific caches within a cluster, which is where I can find stats about total number of gets/puts, average time for each, etc. The MBeans I'm trying to access programatically are visible when I connect to the remote process using JConsole, and have names like this: Coherence:type=Cache,service=SequenceQueue,name=SEQ%GENERATOR,nodeId=1,tier=back It would make it more flexible if I can dynamically grab all type=Cache MBeans for a particular node ID without specifying all the caches. I'm trying to query them like this: QueryExp specifiedNodeId = Query.eq(Query.attr("nodeId"), Query.value(nodeId)); QueryExp typeIsCache = Query.eq(Query.attr("type"), Query.value("Cache")); QueryExp cacheNodes = Query.and(specifiedNodeId, typeIsCache); ObjectName coherence = new ObjectName("Coherence:*"); Set<ObjectName> cacheMBeans = mBeanServer.queryMBeans(coherence, cacheNodes); However, regardless of whether I use queryMBeans() or queryNames(), the query returns a Set containing... ...0 objects if I pass the arguments shown above ...0 objects if I pass null for the first argument ...all MBeans in the Coherence:* domain (112) if I pass null for the second argument ...every single MBean (128) if I pass null for both arguments The first two results are the unexpected ones, and suggest a problem in the QueryExp I'm passing, but I can't figure out what the problem is. I even tried just passing typeIsCache or specifiedNodeId for the second parameter (with either coherence or null as the first parameter) and I always get 0 results. I'm pretty green with JMX — any insight on what the problem is? (FYI, the monitoring tool will be run on Java 5, so things like JMX 2.0 won't help me at this point.)

  Read the article

• Does JAXB work under Java 5?

  - by Arne Evertsson

  Building with maven I get "package javax.xml.bind.annotation does not exists" What do I need to make JAXB work with Java 5?

  Read the article

• Using a version control system as a data backend

  - by JacobM

  I'm involved in a project that, among other things, involves storing edits and changes to a large hierarchical document (HTML-formatted text). We want to include versioning of textual changes and of structural changes. Currently we're maintaining the tree of document sections in a relational database, but as we start working on how to manage versioning of structural changes, it's clear that we're in danger of having to write a lot of the functionality that a version control system provides. We don't want to reinvent the wheel. Is it possible that we could use an existing version control system as the data store, at least for the document itself? Presumably we could do so by writing out new versions to the filesystem, and keeping that directory under version control (and programmatically doing commits and so forth) but it would be better if we could directly interact with the repository via code. The VCS that we are most familiar with is Subversion, but I'm not thrilled with how Subversion represents changes to the directory structure -- it would be nice if we could see that a particular revision included moving a section from Chapter 2 to Chapter 6, rather than just seeing a new version of the tree. This sounds more like the way a system like Mercurial handles changes to the structure. Any advice? Do VCS's have public APIs and so forth? The project is in Java (with Spring) if it matters.

  Read the article

• Liferay: Customise the web.xml HeaderFilter added during portlet deloyment

  - by gid

  I need to customise the deployment of my liferay portlet such that the GWT nocache.js files don't get a 'Expires' HTTP header set. My war file looks like this: view.jsp com.foobar.MyEntryPoint/com.foobar.MyEntryPoint.nocache.js com.foobar.MyEntryPoint/12312312313213123123123.cache.html WEB-INF/web.xml WEB-INF/portlet.xml WEB-INF/liferay-portlet.xml ... etc my web.xml is pretty much empty (only has the displayName) On deployment this is rewritten my liferay to have a series of filters in particalar: Header Filter com.liferay.portal.kernel.servlet.PortalClassLoaderFilter filter-class com.liferay.portal.servlet.filters.header.HeaderFilter Cache-Control max-age=315360000, public Expires 315360000 Header Filter *.js This filter adds an Expires header for about 2020 to the .nocache.js js files... the trouble is these files really shouldn't be cached (the hint is in the name :) For development purposes I have worked around this by disabling the filter using: com.liferay.portal.servlet.filters.header.HeaderFilter=false in portal-ext.properties globaly. What I what I would like to to is one of the following: Disable HeaderFilter only for this portlet or war file. I can always add my own expires Add an init-param to the HeaderFilter to match anything other than .nocache.js files Any ideas how either of these things could be achieved? Stack: liferay-6.0.1 CE, Windows 7, java 1.6.0_18, GWT 2.0.3

  Read the article

• Perl Script in background

  - by himz

  I have a perl script i made to automatically telnet into different servers . but its interface is only command line. To make it more user friendly for general windows users , i need to make GUI for it . My idea is to make GUI in a language like VB,java ,etc and let that call perl script . my script will run in background in a command prompt and whatever the result it displays back in GUI. Got some success. GUI in vb ,I run an instance of CMD in background ,run perl script in that .But that is wer program fails .As perl script runs in a thread for perl , i only get the output when script completes(rather say when it timeout). i need a mechanism where i can interact with the perl script , take output of script and show to user , then take input from user and so on . Please can you all suggest me some way to actually make this happen. PS: No limitation on using any language for GUI (as core work is done by perl script,GUI only there to give appropriate commands to script) Thanks in advance

  Read the article

• HttpURLConnection inside a loop

  - by Carlos Garces

  Hi! I'm trying to connect to one URL that I know that exist but I don't know when. I don't have access to this server so I can't change anything to receive a event. The actual code is this. URL url = new URL(urlName); for(int j = 0 ; j< POOLING && disconnected; j++){ HttpURLConnection connection = (HttpURLConnection) url.openConnection(); int status = connection.getResponseCode(); if(status == HttpURLConnection.HTTP_OK || status == HttpURLConnection.HTTP_NOT_MODIFIED){ //Some work }else{ //wait 3s Thread.sleep(3000); } } Java not is my best skill and I'm not sure if this code is good from the point of view of performance. I'm opening a new connection every 3 seconds? or the connection is reused? If I call to disconnect() I ensure that no new connections are open in the loop, but... it will impact in performance?. Suggestions? What is the fast/best ways to know it a URL exist?

  Read the article

• java.lang.Void in C#?

  - by user313661

  Hi, I am currently working with .Net 2.0 and have an interface whose generic type is used to define a method's return type. Something like interface IExecutor<T> { T Execute() { ... } } My problem is that some classes that implement this interface do not really need to return anything. In Java you can use java.lang.Void for this purpose, but after quite a bit of searching I found no equivalent in C#. More generically, I also did not find a good way around this problem. I tried to find how people would do this with delegates, but found nothing either - which makes me believe that the problem is that I suck at searching :) So what's the best way to solve this? How would you do it? Thanks!

  Read the article

• Optimizing MySQL update query

  - by Jernej Jerin

  This is currently my MySQL UPDATE query, which is called from program written in Java: String query = "UPDATE maxday SET DatePressureREL = (SELECT Date FROM ws3600 WHERE PressureREL = (SELECT MAX" + "(PressureREL) FROM ws3600 WHERE Date >= '" + Date + "') AND Date >= '" + Date + "' ORDER BY Date DESC LIMIT 1), " + "PressureREL = (SELECT PressureREL FROM ws3600 WHERE PressureREL = (SELECT MAX(PressureREL) FROM ws3600 " + "WHERE Date >= '" + Date + "') AND Date >= '" + Date + "' ORDER BY Date DESC LIMIT 1), ..."; try { s.execute(query); } catch (SQLException e) { System.out.println("SQL error"); } catch(Exception e) { e.printStackTrace(); } Let me explain first, what does it do. I have two tables, first is ws3600, which holds columns (Date, PressureREL, TemperatureOUT, Dewpoint, ...). Then I have second table, called maxday, which holds columns like DatePressureREL, PressureREL, DateTemperatureOUT, TemperatureOUT,... Now as you can see from an example, I update each column, the question is, is there a faster way? I am asking this, because I am calling MAX twice, first to find the Date for that value and secondly to find the actual value. Now I know that I could write like that: SELECT Date, PressureREL FROM ws3600 WHERE PressureREL = (SELECT MAX(PressureREL) FROM ws3600 WHERE Date >= '" + Date + "') AND Date >= '" + Date + "' ORDER BY Date DESC LIMIT 1 That way I get the Date of the max and the max value at the same time and then update with those values the data in maxday table. But the problem of this solution is, that I have to execute many queries, which as I understand takes alot more time compared to executing one long mysql query because of overhead in sending each query to the server. If there is no better way, which solution beetwen this two should I choose. The first, which only takes one query but is very unoptimized or the second which is beter in terms of optimization, but needs alot more queries which probably means that the preformance gain is lost because of overhead in sending each query to the server?

  Read the article

• Single Form with Multiple Dynamic Buttons

  - by John Reilly

  I've spent hours/days trying to figure this out and now I'm completely perplexed so I thought I'd give stackoverflow a try. I'm (a newb) working in Java/JSP using Eclipse hosting on Google App Engine trying to develop an app for a volunteer organization I'm a member of. Rather than embarrass myself by showing my current code I'd love just a nudge in the right direction. I have a form (which doubles as a report basically) showing "people" grouped under the "task" they are currently working on. I would like to select multiple people from multiple tasks and reassign them to another task e.g. Bill and Jane are Gardening, Jeff is Painting. I want to select Jane and Jeff (all people have an associated checkbox in the form) and re-assign them to Sweeping (which is a task on the form but has no people assigned to it yet). Ideally, the re-assignment to Sweeping would be via a Sweeping button (each task would have a dynamically-created task button) that would pass the "Sweeping" value to a servlet along with an array or list of people whose checkbox has been checked. The servlet would handle the request (creating an Assignment "object/entity" with timeStamp, personId, taskId) and then re-direct back to the form/report which would then repaint with the current tasks/people generated from the Assignments class in the datastore. All the tasks are user-defined and retrieved from the database when building the form. Ditto the people. I've been trying to keep the jsp for presentation and the servlets for the processing but I'm no purist and would just like to get unstuck. Many thanks in advance for your assistance.

  Read the article

• How to access application.xml file of an EAR deployed to IBM WebSphere 6.1

  - by Matt1776

  I am deploying an EAR file to the IBM WebSpehre server 6.1 - I want to be able to access the EAR application name which is stored in the deployment file under 'display-name'. Looking through stack overflow posts on related subjects, I've been able to gather that this is possible via the Java MBean API - or IBM's WAS API - Problem is I cannot find a place where these API lists are summarized, i.e. cannot figure out which one to begin looking at. I could hardcode the WAS install location and find the file by looking in the 'installedApps' directory, but this is not dynamic. Does anyone have any experience working with these APIs? Any other way to dynamically find the deployed EAR's display name? EDIT - I should add that the reason I would like this information is to dynamically load our properties files - that are named by the following convention "EARAppName.properties" - so you see there IS a reasonable 'rationale' behind desiring this information in my application EDIT 2 - I should also note that this app will always be deployed on a WAS - but in the case that it isnt, a generic non-proprietary solution would be preferred, but not necessary at this moment. EDIT 3 - What I want to accomplish: Is there a way to dynamically find the deployed EAR's display name from within the application code?

  Read the article

• Calling an Oracle PL/SQL procedure with Custom Object return types from 0jdbc6 JDBCthin drivers

  - by Andrew Harmel-Law

  I'm writing some JDBC code which calls a Oracle 11g PL/SQL procdedure which has a Custom Object return type. Whenever I try an register my return types, I get either ORA-03115 or PLS-00306 as an error when the statement is executed depending on the type I set. An example is below: PLSQL Code: Procedure GetDataSummary (p_my_key IN KEYS.MY_KEY%TYPE, p_recordset OUT data_summary_tab, p_status OUT VARCHAR2); Java Code: String query = "beginmanageroleviewdata.getdatasummary(?, ?, ?); end;"); CallableStatement stmt = conn.prepareCall(query); stmt.setInt(1, 83); stmt.registerOutParameter(2, OracleTypes.CURSOR); // Causes error: PLS-00306 stmt.registerOutParameter(3, OracleTypes.VARCHAR); stmt.execute(stmt); // Error mentioned above thrown here. Can anyone provide me with an example showing how I can do this? I guess it's possible. However I can't see a rowset OracleType. CURSOR, REF, DATALINK, and more fail. Apologies if this is a dumb question. I'm not a PL/SQL expert and may have used the wrong terminology in some areas of my question. (If so, please edit me). Thanks in advance. Regs, Andrew

  Read the article

• ClassCastException while using service

  - by Sebi

  I defined a local Service: public class ComService extends Service implements IComService { private IBinder binder = new ComServiceBinder(); public class ComServiceBinder extends Binder implements IComService.IServiceBinder { public IComService getService() { return ComService.this; } } public void test(String msg) { System.out.println(msg); } @Override public IBinder onBind(Intent intent) { return binder; } } The corresponding interface: public interface IComService { public void test(String msg); public interface IServiceBinder { IComService getService(); } } Then i try to bind the service in another activity in another application, where the same interface is available: bindService(new Intent("ch.ifi.csg.games4blue.gamebase.api.ComService"), conn, Context.BIND_AUTO_CREATE); and private ServiceConnection conn = new ServiceConnection() { @Override public void onServiceConnected(ComponentName name, IBinder service) { Log.i("INFO", "Service bound " + name); comService = ((IComService.IServiceBinder)service).getService(); serviceHandler.sendEmptyMessage(0); } @Override public void onServiceDisconnected(ComponentName arg0) { Log.i("INFO", "Service Unbound "); } }; but the line comService = ((IComService.IServiceBinder)service).getService(); always throws a 05-02 22:12:55.922: ERROR/AndroidRuntime(622): java.lang.ClassCastException: android.os.BinderProxy I can't explain why, I followed the app sample on http://developer.android.com/resources/samples/ApiDemos/src/com/example/android/apis/app/LocalServiceBinding.html Any hints would be nice!

  Read the article

• Count all lists of adjacent nodes stored in an array.

  - by Ben Brodie

  There are many naive approaches to this problem, but I'm looking for a good solution. Here is the problem (will be implemented in Java): You have a function foo(int a, int b) that returns true if 'a' is "adjacent" to 'b' and false if 'a' is not adjacent to 'b'. You have an array such as this [1,4,5,9,3,2,6,15,89,11,24], but in reality has a very long length, like 120, and will be repeated over and over (its a genetic algorithm fitness function) which is why efficiency is important. I want a function that returns the length of each possible 'list' of adjacencies in the array, but not including the 'lists' which simply subsets of a larger list. For example, if foo(1,4) - true, foo(4,5) - true, foo(5,9)- false, foo(9,3) & foo(3,2) & foo(2,6), foo(6,15) - true, then there are 'lists' (1,4,5) and (9,3,2,6), so length 3 and 4. I don't want it to return (3,2,6), though, because this is simply a subset of 9,3,2,6. Thanks.

  Read the article

• Help with Neuroph neural network

  - by user359708

  For my graduate research I am creating a neural network that trains to recognize images. I am going much more complex than just taking a grid of RGB values, downsampling, and and sending them to the input of the network, like many examples do. I actually use over 100 independently trained neural networks that detect features, such as lines, shading patterns, etc. Much more like the human eye, and it works really well so far! The problem is I have quite a bit of training data. I show it over 100 examples of what a car looks like. Then 100 examples of what a person looks like. Then over 100 of what a dog looks like, etc. This is quite a bit of training data! Currently I am running at about one week to train the network. This is kind of killing my progress, as I need to adjust and retrain. I am using Neuroph, as the low-level neural network API. I am running a dual-quadcore machine(16 cores with hyperthreading), so this should be fast. My processor percent is at only 5%. Are there any tricks on Neuroph performance? Or Java peroformance in general? Suggestions? I am a cognitive psych doctoral student, and I am decent as a programmer, but do not know a great deal about performance programming.

  Read the article

• Create image from scratch with JMagick

  - by Michael IV

  I am using Java port of ImageMagick called JMagick .I need to be able to create a new image and write an arbitrary text chunk into it.The docs are very poor and what I managed to get so far is to write text into the image which comes from IO.Also , in all the examples I have found it seems like the very first operation ,before writing new image data , is always loading of an existing image into ImageInfo instance.How do I create an image from scratch with JMagick and then write a text into it? Here is what I do now : try { ImageInfo info = new ImageInfo(); info.setSize("512x512"); info.setUnits(ResolutionType.PixelsPerInchResolution); info.setColorspace(ColorspaceType.RGBColorspace); info.setBorderColor(PixelPacket.queryColorDatabase("red")); info.setDepth(8); BufferedImage img = new BufferedImage(512,512,BufferedImage.TYPE_4BYTE_ABGR); byte[] imageBytes = ((DataBufferByte) img.getData().getDataBuffer()).getData(); MagickImage mimage = new MagickImage(info,imageBytes); DrawInfo aInfo = new DrawInfo(info); aInfo.setFill(PixelPacket.queryColorDatabase("green")); aInfo.setUnderColor(PixelPacket.queryColorDatabase("yellow")); aInfo.setOpacity(0); aInfo.setPointsize(36); aInfo.setFont("Arial"); aInfo.setTextAntialias(true); aInfo.setText("JMagick Tutorial"); aInfo.setGeometry("+40+40"); mimage.annotateImage(aInfo); mimage.setFileName("text.jpg"); mimage.writeImage(info); } catch (MagickException ex) { Logger.getLogger(LWJGL_IDOMOO_SIMPLE_TEST.class.getName()).log(Level.SEVERE, null, ex); } It doesn't work , the JVM crashes with access violation as it probably expects for the input image from IO.

  Read the article

• how to use "tab space" while writing in text file

  - by Manu

  SimpleDateFormat formatter = new SimpleDateFormat("ddMMyyyy_HHmmSS"); String strCurrDate = formatter.format(new java.util.Date()); String strfileNm = "Cust_Advice_" + strCurrDate + ".txt"; String strFileGenLoc = strFileLocation + "/" + strfileNm; String strQuery="select name, age, data from basetable; try { stmt = conn.createStatement(); System.out.println("Query is -> " + strQuery); rs = stmt.executeQuery(strQuery); File f = new File(strFileGenLoc); OutputStream os = (OutputStream)new FileOutputStream(f); String encoding = "UTF8"; OutputStreamWriter osw = new OutputStreamWriter(os, encoding); BufferedWriter bw = new BufferedWriter(osw); while (rs.next() ) { bw.write(rs.getString(1)==null? "":rs.getString(1)); bw.write(" "); bw.write(rs.getString(2)==null? "":rs.getString(2)); bw.write(" "); } bw.flush(); bw.close(); } catch (Exception e) { System.out.println( "Exception occured while getting resultset by the query"); e.printStackTrace(); } finally { try { if (conn != null) { System.out.println("Closing the connection" + conn); conn.close(); } } catch (SQLException e) { System.out.println( "Exception occured while closing the connection"); e.printStackTrace(); } } return objArrayListValue; } i need "one tab space" in between each column(while writing to text file). like manu 25 data1 manc 35 data3 in my code i use bw.write(" ") for creating space between each column. how to use "one tab space" in that place instead of giving "space".

  Read the article

• Best architecture for a social media app

  - by Sky

  Hey guys, Im working on promising project that develops a new social media app for web and mobile. We are at begin defining functionalities. Nevertheless, I'm thinking ahead on architecture. So I'm asking: 1 - Whats the best plataform to develop the core of this aplication that will have a Rest API interface. 2 - Whats the best database that will scale and grow with my application. As far as I researched, these were the answers I found most interesting: For database: Cassandra NoSQL DB, amazing scalabilty, amazing write performance, good read performance (will be improved on 0.6). I think i will choose that one. Zookeer for transactions on Cassandra. I think that 2 technologies rly good for that propose. What do you think guys? On the front end that will serve the REST API, i dont have a final candidate. For this one i have questions based on Perfomance X Scalabilty X Fast Development/Maintenance. Java or .Net As far as I researched, brings the best balance of this requisits. Python, pearl and Rail, has the best (Fast Development/Maintenance), but sux on all other. C or C++ I dont even consider, because its (Fast Development/Maintenance) sux... So what do you guy think about it?

  Read the article

• .apk signing fails even with Sun JDK (java.lang.NoClassDefFoundError: com.android.jarutils.DebugKeyP

  - by ianweller

  I'm having an interesting problem signing my Android application, whether or not I'm using a debug key. Regardless of the JDK I have installed to /usr/bin/{java,keytool,jarsigner} (OpenJDK or Sun's JDK) it will always give the following output after compiling successfully: -package-debug-sign: [apkbuilder] Creating RemoteNotify-debug-unaligned.apk and signing it with a debug key... BUILD FAILED /home/ianweller/AndroidSDK/platforms/android-7/templates/android_rules.xml:281: The following error occurred while executing this line: /home/ianweller/AndroidSDK/platforms/android-7/templates/android_rules.xml:152: java.lang.NoClassDefFoundError: com.android.jarutils.DebugKeyProvider The application was built and signed just fine by Eclipse with the ADT plugin (even without Sun's JDK installed). I'm on Fedora 12. I'm wanting to get my code out of Eclipse and move it into a git repository, but being unable to build it from ant will not allow this to happen.

  Read the article

• Overriding equals method without breaking symmetry in a class that has a primary key

  - by Kosta

  Hi, the answer to this question is probably "not possible", but let me ask regardless :) Assuming we have a very simple JAVA class that has a primary key, for example: class Person { String ssid; String name; String address; ... } Now, I want to store people in a collection, meaning I will have to override the equals method. Not a completely trivial matter, but on a bare basis I will have something along the lines of: @Override public boolean equals (Object other) { if(other==this) return true; if(!other.getClass().equals(this.getClass()) return false; Person otherPerson = (Person)other; if(this.ssid.equals(otherPerson.getSsid()) return true; } Excuse any obvious blunders, just typing this out of my head. Now, let's say later on in the application I have a ssid I obtained through user input. If I want to compare my ssid to a Person, I would have to call something like: String mySsid = getFromSomewhere(); Person myPerson = getFromSomewhere(); if(myPerson.equals(new Person(mySsid)) doSomething(); This means I have to create a convenience constructor to create a Person based on ssid (if I don't already have one), and it's also quite verbose. It would be much nicer to simply call myPerson.equals(mySsid) but if I added a string comparison to my Person equals class, that would break the symmetry property, since the String hasn't got a clue on how to compare itself to a Person. So finally, the big question, is there any way to enable this sort of "shorthand" comparisons using the overriden equals method, and without breaking the symmetry rule? Thanks for any thoughts on this!

  Read the article

< Previous Page | 639 640 641 642 643 644 645 646 647 648 649 650  | Next Page >