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  • JTable row filters updates

    - by Jeff Storey
    Is there a way to tell a JTable's row filter that it should update itself to display the filtered data? I'm currently using the fireTableDataChanged method in the AbstractTableModel but the underlying data for the table isn't actually changing, so this seems like it might be wasteful. The way my filter works is to check if data in the table is in some other list and only display it if it is in that list. So that other list changed and I need to tell the filter to refresh itself. Is fireTableDataChanged the correct way to do this? thanks, Jeff

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  • Use case of Glass Pane vs. Layered Pane

    - by Amanda S
    I've always been a little fuzzy on the difference between the glass pane and a layered pane. Is the glass pane essentially just "the very top layer of the root pane," or does it behave differently? When would you use a layered pane instead of the glass pane?

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  • WTK emulator bluetooth connection problem

    - by Gokhan B.
    Hi! I'm developing a J2ME program with eclipse / WTK 2.5.2 and having problem with connecting two emulators using bluetooth. There is one server and one .client running on two different emulators. The problem is client program cannot discover any bluetooth device. Here is the server and client codes: public Server() { try { LocalDevice local = LocalDevice.getLocalDevice(); local.setDiscoverable(DiscoveryAgent.GIAC); server = (StreamConnectionNotifier) Connector.open("btspp://localhost:" + UUID_STRING + ";name=" + SERVICE_NAME); Util.Log("EchoServer() Server connector open!"); } catch (Exception e) {} } after calling Connector.open, I get following warning in console, which i believe is related: Warning: Unregistered device: unspecified and client code that searches for devices: public SearchForDevices(String uuid, String nm) { UUIDStr = uuid; srchServiceName = nm; try { LocalDevice local = LocalDevice.getLocalDevice(); agent = local.getDiscoveryAgent(); deviceList = new Vector(); agent.startInquiry(DiscoveryAgent.GIAC, this); // non-blocking } catch (Exception e) {} } system never calls deviceDiscovered, but calls inquiryCompleted() with INQUIRY_COMPLETED paramter, so I suppose client program runs fine. Bluetooth is enabled at emulator settings.. any ideas ?

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  • 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!

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  • Dependency on Spring's annotations

    - by Jacques René Mesrine
    I have annotated my classes with @Repository, @Resource, @Component, @Service annotations but these classes must run in 2 environments. The first environment is Spring 2.x based while the other has no spring at all. I'm sure the code will fail without the spring jars & I want to know ideas from you on how I can retain the annotations but still work in both environments

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  • ThreadPooler in Spring 2.5.6

    - by MiKu
    My application uses Spring 2.5.6. I have a service that creates explicit threads for some specific task. Triggering of this service call happens through quartz time scheduler. Question : While executing service calls, i want to use some sort of thread pooler that can return me thread instances. Is there any implementations that i can use in Spring?

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  • Best Maven plugins

    - by ripper234
    We are just moving to Maven, and I understand there is a world of different plugins & extensions. Which are the best ones you recommend for general usage? (On plugin per answer please)

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  • Why is Swing Parser's handleText not handling nested tags?

    - by Jim P
    I need to transform some HTML text that has nested tags to decorate 'matches' with a css attribute to highlight it (like firefox search). I can't just do a simple replace (think if user searched for "img" for example), so I'm trying to just do the replace within the body text (not on tag attributes). I have a pretty straightforward HTML parser that I think should do this: final Pattern pat = Pattern.compile(srch, Pattern.CASE_INSENSITIVE); Matcher m = pat.matcher(output); if (m.find()) { final StringBuffer ret = new StringBuffer(output.length()+100); lastPos=0; try { new ParserDelegator().parse(new StringReader(output.toString()), new HTMLEditorKit.ParserCallback () { public void handleText(char[] data, int pos) { ret.append(output.subSequence(lastPos, pos)); Matcher m = pat.matcher(new String(data)); ret.append(m.replaceAll("<span class=\"search\">$0</span>")); lastPos=pos+data.length; } }, false); ret.append(output.subSequence(lastPos, output.length())); return ret; } catch (Exception e) { return output; } } return output; My problem is, when I debug this, the handleText is getting called with text that includes tags! It's like it's only going one level deep. Anyone know why? Is there some simple thing I need to do to HTMLParser (haven't used it much) to enable 'proper' behavior of nested tags? PS - I figured it out myself - see answer below. Short answer is, it works fine if you pass it HTML, not pre-escaped HTML. Doh! Hope this helps someone else. <span>example with <a href="#">nested</a> <p>more nesting</p> </span> <!-- all this gets thrown together -->

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  • Defining jUnit Test cases Correctly

    - by Epitaph
    I am new to Unit Testing and therefore wanted to do some practical exercise to get familiar with the jUnit framework. I created a program that implements a String multiplier public String multiply(String number1, String number2) In order to test the multiplier method, I created a test suite consisting of the following test cases (with all the needed integer parsing, etc) @Test public class MultiplierTest { Multiplier multiplier = new Multiplier(); // Test for 2 positive integers assertEquals("Result", 5, multiplier.multiply("5", "1")); // Test for 1 positive integer and 0 assertEquals("Result", 0, multiplier.multiply("5", "0")); // Test for 1 positive and 1 negative integer assertEquals("Result", -1, multiplier.multiply("-1", "1")); // Test for 2 negative integers assertEquals("Result", 10, multiplier.multiply("-5", "-2")); // Test for 1 positive integer and 1 non number assertEquals("Result", , multiplier.multiply("x", "1")); // Test for 1 positive integer and 1 empty field assertEquals("Result", , multiplier.multiply("5", "")); // Test for 2 empty fields assertEquals("Result", , multiplier.multiply("", "")); In a similar fashion, I can create test cases involving boundary cases (considering numbers are int values) or even imaginary values. 1) But, what should be the expected value for the last 3 test cases above? (a special number indicating error?) 2) What additional test cases did I miss? 3) Is assertEquals() method enough for testing the multiplier method or do I need other methods like assertTrue(), assertFalse(), assertSame() etc 4) Is this the RIGHT way to go about developing test cases? How am I "exactly" benefiting from this exercise? 5)What should be the ideal way to test the multiplier method? I am pretty clueless here. If anyone can help answer these queries I'd greatly appreciate it. Thank you.

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  • Basic jUnit Questions

    - by Epitaph
    I was testing a String multiplier class with a multiply() method that takes 2 numbers as inputs (as String) and returns the result number (as String) `public String multiply(String num1, String num2); I have done the implementation and created a test class with the following test cases involving the input String parameter as 1) valid numbers 2) characters 3) special symbol 4) empty string 5) Null value 6) 0 7) Negative number 8) float 9) Boundary values 10) Numbers that are valid but their product is out of range 11) numbers will + sign (+23) 1) I'd like to know if "each and every" assertEquals() should be in it's own test method? Or, can I group similar test cases like testInvalidArguments() to contains all asserts involving invalid characters since ALL of them throw the same NumberFormatException ? 2) If testing an input value like character ("a"), do I need to include test cases for ALL scenarios? "a" as the first argument "a" as the second argument "a" and "b" as the 2 arguments 3) As per my understanding, the benefit of these unit tests is to find out the cases where the input from a user might fail and result in an exception. And, then we can give the user with a meaningful message (asking them to provide valid input) instead of an exception. Is that the correct? And, is it the only benefit? 4) Are the 11 test cases mentioned above sufficient? Did I miss something? Did I overdo? When is enough? 5) Following from the above point, have I successfully tested the multiply() method?

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  • UriBuilder incorrectly encoding Query Parameters value ?

    - by Fred
    Lets consider the following code sample where a path and single parameter are encoded... Parameter name: "param" Parameter value: "foo/bar?aaa=bbb&ccc=ddd" (happens to be a url with query parameters) String test = UriBuilder.fromPath("https://dummy.com"). queryParam("param", "foo/bar?aaa=bbb&ccc=ddd"). build().toURL().toString(); The encoded URL string returned is: "https://dummy.com?param=foo/bar?aaa%3Dbbb&ccc%3Dddd" Is this correct ? Should not the character "&" (and may be even "?") be encoded in the parameter value string ? Would not the URL produced be interpreted as follow: One first parameter, name="param", value = "ar?aaa%3Dbbb" followed by a second parameter, name="ccc%3Dddd", without value.

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  • Casting To The Correct Subclass

    - by kap
    Hi Guys I hava a supeclass called Car with 3 subclasses. class Ford extends Car{ } class Chevrolet extends Car{ } class Audi extends Car{ } Now i have a function called printMessge(Car car) which will print a message of a particular car type. In the implementation i use if statements to test the instance of the classes like this. public int printMessge(Car car){ if((Ford)car instanceof Ford){ // print ford }else if((Chevrolet)car instanceof Chevrolet){ // print chevrolet }else if((Audi)car instanceof Audi){ // print Audi } } for instance if i call it for the first time with Ford printMessge(new Ford()), it prints the ford message but when i call it with printMessge(new Chevrolet()), i get EXCEPTION from the first if statement that Chevrolet cannot be cast to Ford. What am i doing wrong and what is the best way. thanks

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  • 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

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  • Delivery of JMS message before the transaction is committed

    - by ewernli
    Hi, I have a very simple scenario involving a database and a JMS in an application server (Glassfish). The scenario is dead simple: 1. an EJB inserts a row in the database and sends a message. 2. when the message is delivered with an MDB, the row is read and updated. The problem is that sometimes the message is delivered before the insert has been committed in the database. This is actually understandable if we consider the 2 phase commit protocol: 1. prepare JMS 2. prepare database 3. commit JMS 4. ( tiny little gap where message can be delivered before insert has been committed) 5. commit database I've discussed this problem with others, but the answer was always: "Strange, it should work out of the box". My questions are then: How could it work out-of-the box? My scenario sounds fairly simple, why isn't there more people with similar troubles? Am I doing something wrong? Is there a way to solve this issue correctly? Here are a bit more details about my understanding of the problem: This timing issue exist only if the participant are treated in this order. If the 2PC treats the participants in the reverse order (database first then message broker) that should be fine. The problem was randomly happening but completely reproducible. I found no way to control the order of the participants in the distributed transactions in the JTA, JCA and JPA specifications neither in the Glassfish documentation. We could assume they will be enlisted in the distributed transaction according to the order when they are used, but with an ORM such as JPA, it's difficult to know when the data are flushed and when the database connection is really used. Any idea?

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  • Quartz Thread Execution Parallel or Sequential?

    - by vikas
    We have a quartz based scheduler application which runs about 1000 jobs per minute which are evenly distributed across seconds of each minute i.e. about 16-17 jobs per second. Ideally, these 16-17 jobs should fire at same time, however our first statement, which simply logs the time of execution, of execute method of the job is being called very late. e.g. let us assume we have 1000 jobs scheduled per minute from 05:00 to 05:04. So, ideally the job which is scheduled at 05:03:50 should have logged the first statement of the execute method at 05:03:50, however, it is doing it at about 05:06:38. I have tracked down the time taken by the scheduled job which comes around 15-20 milliseconds. This scheduled job is fast enough because we just send a message on an ActiveMQ queue. We have specified the number of threads of quartz to be 100 and even tried with increasing it to 200 and more, but no gain. One more thing we noticed is that logs from scheduler are coming sequential after first 1 minute i.e. [Quartz_Worker_28] <Some log statement> .. .. [Quartz_Worker_29] <Some log statement> .. .. [Quartz_Worker_30] <Some log statement> .. .. So it suggesting that after some time quartz is running threads almost sequential. May be this is happening due to the time taken in notifying the job completion to persistence store (which is a separate postgres database in this case) and/or context switching. What can be the reason behind this strange behavior? EDIT: More detailed Log [06/07/12 10:08:37:192][QuartzScheduler_Worker-34][INFO] org.quartz.plugins.history.LoggingTriggerHistoryPlugin - Trigger [<trigger_name>] fired job [<job_name>] scheduled at: 06-07-2012 10:08:33.458, next scheduled at: 06-07-2012 10:34:53.000 [06/07/12 10:08:37:192][QuartzScheduler_Worker-34][INFO] <my_package>.scheduler.quartz.ScheduledLocateJob - execute begin--------- ScheduledLocateJob with key: <job_name> started at Fri Jul 06 10:08:37 EDT 2012 [06/07/12 10:08:37:192][QuartzScheduler_Worker-34][INFO] <my_package>.scheduler.quartz.ScheduledLocateJob <some log statement> [06/07/12 10:08:37:192][QuartzScheduler_Worker-34][INFO] <my_package>.scheduler.quartz.ScheduledLocateJob <some log statement> [06/07/12 10:08:37:192][QuartzScheduler_Worker-34][INFO] <my_package>.scheduler.quartz.ScheduledLocateJob <some log statement> [06/07/12 10:08:37:220][QuartzScheduler_Worker-34][INFO] <my_package>.scheduler.quartz.ScheduledLocateJob - execute end--------- ScheduledLocateJob with key: <job_name> ended at Fri Jul 06 10:08:37 EDT 2012 [06/07/12 10:08:37:220][QuartzScheduler_Worker-34][INFO] org.quartz.plugins.history.LoggingTriggerHistoryPlugin - Trigger [<trigger_name>] completed firing job [<job_name>] with resulting trigger instruction code: DO NOTHING. Next scheduled at: 06-07-2012 10:34:53.000 I am doubting on this section of the above log scheduled at: 06-07-2012 10:08:33.458, next scheduled at: 06-07-2012 10:34:53.000 because this job was scheduled for 10:04:53, but it fired at 10:08:33 and still quartz didn't consider it as misfire. Shouldn't it be a misfire?

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  • How do I send an email with embedded images AND regular attachments in JavaMail?

    - by Chris
    Hi, I'd like to know how to build an SMTP multipart message in the correct order so that it will render correctly on the iPhone mail client (rendering correctly in GMail). I'm using Javamail to build up an email containing the following parts: A body part with content type "text/html; UTF-8" An embedded image attachment. A file attachment I am sending the mail via GMail SMTP (via SSL) and the mail is sent and rendered correctly using a GMail account, however, the mail does not render correctly on the iPhone mail client. On the iPhone mail client, the image is rendered before the "Before Image" text when it should be rendered afterwards. After the "Before Image" text there is an icon with a question mark (I assume it means it couldn't find the referenced CID). I'm not sure if this is a limitation of the iPhone mail client or a bug in my mail sending code (I strongly assume the latter). I think that perhaps the headers on my parts might by incorrect or perhaps I am providing the multiparts in the wrong order. I include the text of the received mail as output by gmail (which renders the file correc Message-ID: <[email protected]> Subject: =?UTF-8?Q?Test_from_=E3=82=AF=E3=83=AA=E3=82=B9?= MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="----=_Part_0_20870565.1274154021755" ------=_Part_0_20870565.1274154021755 Content-Type: application/octet-stream Content-Transfer-Encoding: base64 Content-ID: <20100518124021763_368238_0> iVBORw0K ----- TRIMMED FOR CONCISENESS 6p1VVy4alAAAAABJRU5ErkJggg== ------=_Part_0_20870565.1274154021755 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 7bit <html><head><title>Employees Favourite Foods</title> <style> body { font: normal 8pt arial; } th { font: bold 8pt arial; white-space: nowrap; } td { font: normal 8pt arial; white-space: nowrap; } </style></head><body> Before Image<br><img src="cid:20100518124021763_368238_0"> After Image<br><table border="0"> <tr> <th colspan="4">Employees Favourite Foods</th> </tr> <tr> <th align="left">Name</th><th align="left">Age</th><th align="left">Tel.No</th><th align="left">Fav.Food</th> </tr> <tr style="background-color:#e0e0e0"> <td>Chris</td><td>34</td><td>555-123-4567</td><td>Pancakes</td> </tr> </table></body></html> ------=_Part_0_20870565.1274154021755 Content-Type: text/plain; charset=us-ascii; name=textfile.txt Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=textfile.txt This is a textfile with numbers counting from one to ten beneath this line: one two three four five six seven eight nine ten(no trailing carriage return) ------=_Part_0_20870565.1274154021755-- Even if you can't assist me with this, I would appreciate it if any members of the forum could forward me a (non-personal) mail that includes inline images (not external hyperlinked images though). I just need to find a working sample then I can move past this. Thanks, Chris.

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  • Atomikos with Hibernate will exhaust db connections

    - by peter
    I am testing an application (Spring 2.5, Hibernate 3.5.0 Beta, Atomikos 3.6.2, and Postgreql 8.4.2) with the configuration for the DAO listed below. The problem that I see is that the pool of 10 connections with the dataSource gets exhausted after the 10's transaction. I know 'hibernate.connection.release_mode' has no effect unless the session is obtained with openSession rather then using a contextual session. I am wandering if anyone has found a way to instruct atomikos code to release connections after any transaction. Thank you Peter <bean id="dataSource" class="com.atomikos.jdbc.AtomikosDataSourceBean" init-method="init" destroy-method="close"> <property name="uniqueResourceName"><value>XADBMS</value></property> <property name="xaDataSourceClassName"> <value>org.postgresql.xa.PGXADataSource</value> </property> <property name="xaProperties"> <props> <prop key="databaseName">${jdbc.name}</prop> <prop key="serverName">${jdbc.server}</prop> <prop key="portNumber">${jdbc.port}</prop> <prop key="user">${jdbc.username}</prop> <prop key="password">${jdbc.password}</prop> </props> </property> <property name="poolSize"><value>10</value></property> </bean> <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"> <property name="dataSource"> <ref bean="dataSource" /> </property> <property name="mappingResources"> <list> <value>Abc.hbm.xml</value> </list> </property> <property name="hibernateProperties"> <props> <prop key="hibernate.dialect">org.hibernate.dialect.PostgreSQLDialect</prop> <prop key="hibernate.show_sql">on</prop> <prop key="hibernate.format_sql">true</prop> <prop key="hibernate.connection.isolation">3</prop> <prop key="hibernate.current_session_context_class">jta</prop> <prop key="hibernate.transaction.factory_class">org.hibernate.transaction.JTATransactionFactory</prop> <prop key="hibernate.transaction.manager_lookup_class">com.atomikos.icatch.jta.hibernate3.TransactionManagerLookup</prop> <prop key="hibernate.connection.release_mode">auto</prop> <prop key="hibernate.current_session_context_class">org.hibernate.context.JTASessionContext</prop> <prop key="hibernate.transaction.auto_close_session">true</prop> </props> </property> </bean> <!-- Transaction definition here --> <bean id="userTransactionService" class="com.atomikos.icatch.config.UserTransactionServiceImp" init-method="init" destroy-method="shutdownForce"> <constructor-arg> <props> <prop key="com.atomikos.icatch.service"> com.atomikos.icatch.standalone.UserTransactionServiceFactory </prop> </props> </constructor-arg> </bean> <!-- Construct Atomikos UserTransactionManager, needed to configure Spring --> <bean id="AtomikosTransactionManager" class="com.atomikos.icatch.jta.UserTransactionManager" init-method="init" destroy-method="close" depends-on="userTransactionService"> <property name="forceShutdown" value="false" /> </bean> <!-- Also use Atomikos UserTransactionImp, needed to configure Spring --> <bean id="AtomikosUserTransaction" class="com.atomikos.icatch.jta.UserTransactionImp" depends-on="userTransactionService"> <property name="transactionTimeout" value="300" /> </bean> <!-- Configure the Spring framework to use JTA transactions from Atomikos --> <bean id="txManager" class="org.springframework.transaction.jta.JtaTransactionManager" depends-on="userTransactionService"> <property name="transactionManager" ref="AtomikosTransactionManager" /> <property name="userTransaction" ref="AtomikosUserTransaction" /> </bean> <!-- the transactional advice (what 'happens'; see the <aop:advisor/> bean below) --> <tx:advice id="txAdvice" transaction-manager="txManager"> <tx:attributes> <!-- all methods starting with 'get' are read-only --> <tx:method name="get*" read-only="true" propagation="REQUIRED"/> <!-- other methods use the default transaction settings (see below) --> <tx:method name="*" propagation="REQUIRED"/> </tx:attributes> </tx:advice> <aop:config> <aop:advisor pointcut="execution(* *.*.AbcDao.*(..))" advice-ref="txAdvice"/> </aop:config> <!-- DAO objects --> <bean id="abcDao" class="test.dao.impl.HibernateAbcDao" scope="singleton"> <property name="sessionFactory" ref="sessionFactory"/> </bean>

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  • Why does Maven have such a bad rep?

    - by Dan
    There is a lot of talk on the internet about how Maven is bad. I have been using some features of Maven for a few years now and the most important benefit in my view is the dependency management. Maven documentation is less than adequate, but generally when I need to accomplish something I figure it once and than it works (for example, I remember when I implemented signing the jars.) I don’t think that Maven is great, but it does solve some problems that without it would be a genuine pain. So, why does Maven has such a bad rep and what problems with Maven can I expect in the future? Maybe there are much better alternatives that I don't know about? (For example, I never looked Ivy in detail.) NOTE: This is not an attempt to cause an argument. It is an attempt to clear the FUD.

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  • Frame Showing Problem

    - by Nitz
    Hey Guys I have made one project which is showing the inventory of the stock of one store. In that inventory the software should store data of the products with their images. There is one problem... Bcz of the lots of stock, the screen on which is image is loading taking a lot of time. So, i thought i should give the frame in which there will be on label which will show the "Loading Software". But now when i am setting visible = true for that frame, but bcz of that images screen class loading problem my frame is not showing correctly. I have put screen shot, now my code. JFrame f; try{ f = new JFrame("This is a test"); f.setSize(300, 300); Container content = f.getContentPane(); content.setBackground(Color.white); content.setLayout(new FlowLayout()); JLabel jl = new JLabel(); jl.setText("Loading Please Wait...."); content.add(jl); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.setVisible(true); }catch(Exception e){ e.printStackTrace(); } initComponents(); try { addInverntory = new AddInventoryScreen(); showstock = new showStock(); // this class will take big time. mf = new mainForm(); f.setVisible(false); }catch (Exception ex) { ex.printStackTrace(); } How Can show some message that, other class is loading or "Loading Software" kind of thing in this situation. Just For the know....this class is not screen on which the image will load.

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  • Using UUIDs for cheap equals() and hashCode()

    - by Tom McIntyre
    I have an immutable class, TokenList, which consists of a list of Token objects, which are also immutable: @Immutable public final class TokenList { private final List<Token> tokens; public TokenList(List<Token> tokens) { this.tokens = Collections.unmodifiableList(new ArrayList(tokens)); } public List<Token> getTokens() { return tokens; } } I do several operations on these TokenLists that take multiple TokenLists as inputs and return a single TokenList as the output. There can be arbitrarily many TokenLists going in, and each can have arbitrarily many Tokens. These operations are expensive, and there is a good chance that the same operation (ie the same inputs) will be performed multiple times, so I would like to cache the outputs. However, performance is critical, and I am worried about the expense of performing hashCode() and equals() on these objects that may contain arbitrarily many elements (as they are immutable then hashCode could be cached, but equals will still be expensive). This led me to wondering whether I could use a UUID to provide equals() and hashCode() simply and cheaply by making the following updates to TokenList: @Immutable public final class TokenList { private final List<Token> tokens; private final UUID uuid; public TokenList(List<Token> tokens) { this.tokens = Collections.unmodifiableList(new ArrayList(tokens)); this.uuid = UUID.randomUUID(); } public List<Token> getTokens() { return tokens; } public UUID getUuid() { return uuid; } } And something like this to act as a cache key: @Immutable public final class TopicListCacheKey { private final UUID[] uuids; public TopicListCacheKey(TopicList... topicLists) { uuids = new UUID[topicLists.length]; for (int i = 0; i < uuids.length; i++) { uuids[i] = topicLists[i].getUuid(); } } @Override public int hashCode() { return Arrays.hashCode(uuids); } @Override public boolean equals(Object other) { if (other == this) return true; if (other instanceof TopicListCacheKey) return Arrays.equals(uuids, ((TopicListCacheKey) other).uuids); return false; } } I figure that there are 2^128 different UUIDs and I will probably have at most around 1,000,000 TokenList objects active in the application at any time. Given this, and the fact that the UUIDs are used combinatorially in cache keys, it seems that the chances of this producing the wrong result are vanishingly small. Nevertheless, I feel uneasy about going ahead with it as it just feels 'dirty'. Are there any reasons I should not use this system? Will the performance costs of the SecureRandom used by UUID.randomUUID() outweigh the gains (especially since I expect multiple threads to be doing this at the same time)? Are collisions going to be more likely than I think? Basically, is there anything wrong with doing it this way?? Thanks.

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  • Why aren't APT generated classes being compiled by Eclipse?

    - by yamsha
    In my Eclipse project I'm using a third-party annotation processor, Hibernate Metamodel Generator to be exact. The annotation processor works as expected and generates files as specified by the spec. These files are generated inside the directory of the Eclipse project under a "gen" folder. In the project properties this is correctly reflected since two source folders exist - "src" and "gen." However, when the project is built for some reason all the [generated] sources under "gen" are not compiled (checking the "bin" directory I only see .class file from the "src" directory). Does anyone know why this is happening?

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  • How do I determine that an instance of org.apache.poi.hwpf.model.ListData belongs to a numbered lis

    - by leighgordy
    Is there a way to determine if an instance of a org.apache.poi.hwpf.model.ListData belongs to a numbered list or bulleted list? I am using Apache Poi's org.apache.poi.hwpf.HWPFDocument class to read the contents of a word document in order to generate HTML. I can identify the list items in the document by checking to see that the paragraph I am working with is an instance of org.apache.poi.hwpf.model.ListData. I can not find a way to determine if ListData belongs to a bulleted list or a numbered list.

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