Search Results

Search found 1977 results on 80 pages for 'concurrent modification'.

Page 25/80 | < Previous Page | 21 22 23 24 25 26 27 28 29 30 31 32  | Next Page >

  • Circular reference with entity manager factory

    - by CodesLikeA_Mokey
    Every time I try and start my app, I get this error on startup: SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor#0': Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'identityAccessAppConfig': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.package.identityaccess.identity.UserRepository com.package.identityaccess.IdentityAccessAppConfig.userRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userRepository': Cannot create inner bean '(inner bean)' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#1': Cannot resolve reference to bean 'identityAccessEntityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.BeanCurrentlyInCreationException: Error creating bean with name 'identityAccessEntityManagerFactory': Requested bean is currently in creation: Is there an unresolvable circular reference? at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:529) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:198) at org.springframework.context.support.AbstractApplicationContext.registerBeanPostProcessors(AbstractApplicationContext.java:741) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:464) at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:389) at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:294) at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:112) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4797) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5291) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334) at java.util.concurrent.FutureTask.run(FutureTask.java:166) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:722) Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'identityAccessAppConfig': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.package.identityaccess.identity.UserRepository com.package.identityaccess.IdentityAccessAppConfig.userRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userRepository': Cannot create inner bean '(inner bean)' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#1': Cannot resolve reference to bean 'identityAccessEntityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.BeanCurrentlyInCreationException: Error creating bean with name 'identityAccessEntityManagerFactory': Requested bean is currently in creation: Is there an unresolvable circular reference? at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:288) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1116) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194) at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:353) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1025) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:921) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:487) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:198) at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:438) at org.springframework.beans.factory.BeanFactoryUtils.beansOfTypeIncludingAncestors(BeanFactoryUtils.java:277) at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.detectPersistenceExceptionTranslators(PersistenceExceptionTranslationInterceptor.java:139) at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.<init>(PersistenceExceptionTranslationInterceptor.java:79) at org.springframework.dao.annotation.PersistenceExceptionTranslationAdvisor.<init>(PersistenceExceptionTranslationAdvisor.java:71) at org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor.setBeanFactory(PersistenceExceptionTranslationPostProcessor.java:85) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeAwareMethods(AbstractAutowireCapableBeanFactory.java:1502) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1470) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:521) ... 20 more Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.package.identityaccess.identity.UserRepository com.package.identityaccess.IdentityAccessAppConfig.userRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userRepository': Cannot create inner bean '(inner bean)' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#1': Cannot resolve reference to bean 'identityAccessEntityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.BeanCurrentlyInCreationException: Error creating bean with name 'identityAccessEntityManagerFactory': Requested bean is currently in creation: Is there an unresolvable circular reference? at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:514) at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:87) at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:285) ... 45 more Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userRepository': Cannot create inner bean '(inner bean)' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#1': Cannot resolve reference to bean 'identityAccessEntityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.BeanCurrentlyInCreationException: Error creating bean with name 'identityAccessEntityManagerFactory': Requested bean is currently in creation: Is there an unresolvable circular reference? at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:282) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:126) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1387) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1128) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194) at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:912) at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:855) at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:770) at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:486) ... 47 more Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#1': Cannot resolve reference to bean 'identityAccessEntityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.BeanCurrentlyInCreationException: Error creating bean with name 'identityAccessEntityManagerFactory': Requested bean is currently in creation: Is there an unresolvable circular reference? at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:329) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:107) at org.springframework.beans.factory.support.ConstructorResolver.resolveConstructorArguments(ConstructorResolver.java:615) at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:441) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1025) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:921) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:487) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:271) ... 60 more Caused by: org.springframework.beans.factory.BeanCurrentlyInCreationException: Error creating bean with name 'identityAccessEntityManagerFactory': Requested bean is currently in creation: Is there an unresolvable circular reference? at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.beforeSingletonCreation(DefaultSingletonBeanRegistry.java:327) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:217) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:323) I am new to configuring spring through java and have been spinning circles for days. I have my application which includes 2 separate modules. The identity-access module will handle user and access information and will have a datasource to an older database. The other module module2 will eventually have its own database. Here are the config files: application: @Configuration @EnableWebMvc @ComponentScan(basePackages = "com.package.myapp.web") @ImportResource({"classpath:com/package/appbase/appbase-context.xml"}) @Import(com.package.identityaccess.IdentityAccessAppConfig.class) public class IMSAppConfig extends WebMvcConfigurerAdapter { @Override public void addResourceHandlers(ResourceHandlerRegistry registry) { registry.addResourceHandler("/resources/**").addResourceLocations("ims/resources/"); } } identity-access: @Configuration @ComponentScan(basePackages = "com.package.identityaccess") @EnableJpaRepositories(entityManagerFactoryRef = "identityAccessEntityManagerFactory", value = "com.package.identityaccess") @EnableTransactionManagement public class IdentityAccessAppConfig { @Autowired UserRepository userRepository; @Bean public DataSource identityAccessDataSource() throws IOException, SQLException { return new SelfConfiguringBasicDataSource(System.getProperty("db_properties_path") + "/dev.oracle.properties", ""); } @Bean public Map<String, Object> identityAccessJpaProperties() { Map<String, Object> props = new HashMap<>(); props.put("eclipselink.weaving", "false"); props.put("eclipselink.target-database", OraclePlatform.class.getName()); return props; } @Bean public JpaVendorAdapter identityAccessJpaVendorAdapter() { EclipseLinkJpaVendorAdapter eclipseLinkJpaVendorAdapter = new EclipseLinkJpaVendorAdapter(); eclipseLinkJpaVendorAdapter.setDatabasePlatform(OraclePlatform.class.getName()); eclipseLinkJpaVendorAdapter.setGenerateDdl(false); eclipseLinkJpaVendorAdapter.setShowSql(true); return eclipseLinkJpaVendorAdapter; } @Bean public PlatformTransactionManager identityAccessTransactionManager() throws IOException, SQLException { JpaTransactionManager txManager = new JpaTransactionManager(); txManager.setEntityManagerFactory(identityAccessEntityManagerFactory().getObject()); return txManager; } @Bean public LocalContainerEntityManagerFactoryBean identityAccessEntityManagerFactory() throws IOException, SQLException { LocalContainerEntityManagerFactoryBean lef = new LocalContainerEntityManagerFactoryBean(); lef.setDataSource(identityAccessDataSource()); lef.setJpaPropertyMap(identityAccessJpaProperties()); lef.setJpaVendorAdapter(identityAccessJpaVendorAdapter()); lef.setPackagesToScan("com.package.identityaccess"); return lef; } @Bean public AuthenticationService authenticationService() { return new AuthenticationServiceImpl(userRepository); } } module2: @Configuration @ComponentScan(basePackages = "com.package.myapp.core") @EnableJpaRepositories("com.package.myapp.core.domain") @EnableTransactionManagement public class ModuleTwoAppConfig { @Bean public DataSource dataSource() { EmbeddedDatabaseBuilder embeddedDatabaseBuilder = new EmbeddedDatabaseBuilder(); embeddedDatabaseBuilder.setType(EmbeddedDatabaseType.HSQL); embeddedDatabaseBuilder.addScript("setup.sql"); return embeddedDatabaseBuilder.build(); } @Bean public Map<String, Object> jpaProperties() { Map<String, Object> props = new HashMap<>(); props.put("eclipselink.weaving", "false"); props.put("eclipselink.ddl-generation", "create-tables"); props.put("eclipselink.target-database", HSQLPlatform.class.getName()); return props; } @Bean public JpaVendorAdapter jpaVendorAdapter() { EclipseLinkJpaVendorAdapter eclipseLinkJpaVendorAdapter = new EclipseLinkJpaVendorAdapter(); eclipseLinkJpaVendorAdapter.setDatabasePlatform(HSQLPlatform.class.getName()); eclipseLinkJpaVendorAdapter.setGenerateDdl(true); eclipseLinkJpaVendorAdapter.setShowSql(true); return eclipseLinkJpaVendorAdapter; } @Bean public PlatformTransactionManager transactionManager() { JpaTransactionManager txManager = new JpaTransactionManager(); txManager.setEntityManagerFactory(entityManagerFactory().getObject()); return txManager; } @Bean public LocalContainerEntityManagerFactoryBean entityManagerFactory() { LocalContainerEntityManagerFactoryBean lef = new LocalContainerEntityManagerFactoryBean(); lef.setDataSource(dataSource()); lef.setJpaPropertyMap(jpaProperties()); lef.setJpaVendorAdapter(jpaVendorAdapter()); lef.setPackagesToScan("com.package.myapp.core.domain"); return lef; } } UserRepository (uses spring-data): public interface UserRepository extends JpaRepository<User, Long> { @Query("select u from User u where u.user_id = ?1") User findByUserId(String userId); } Can you see any problems with what I've done?

    Read the article

  • Java RMI timeout in callback

    - by sakra
    We are using Java RMI for communication. An RMI client passes a processing request and an object with a callback method to an RMI server. The server invokes the callback when it is done with processing. The setup is similar to the one described in RMI Callbacks. Occasionally we are getting a "read time out" exception in the server upon invoking the callback method. The callback thread stalls for about a minute before the exception is raised. java.rmi.ConnectIOException: error during JRMP connection establishment; nested exception is: java.net.SocketTimeoutException: Read timed out at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:286) at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:184) at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:110) at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod(RemoteObjectInvocationHandler.java:178) at java.rmi.server.RemoteObjectInvocationHandler.invoke(RemoteObjectInvocationHandler.java:132) at $Proxy2.finished(Unknown Source) at com.unrisk.db.grid.GridTask.invokeCallback(com.unrisk.db.grid.GridTask:1292) at com.unrisk.db.grid.GridTask.invokeCallbacks(com.unrisk.db.grid.GridTask:1304) at com.unrisk.db.service.tasks.EquityMDTask.afterRun(com.unrisk.db.service.tasks.EquityMDTask:276) at com.unrisk.db.grid.GridTask.run(com.unrisk.db.grid.GridTask:720) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:619) Caused by: java.net.SocketTimeoutException: Read timed out at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.read(SocketInputStream.java:129) at java.io.BufferedInputStream.fill(BufferedInputStream.java:218) at java.io.BufferedInputStream.read(BufferedInputStream.java:237) at java.io.DataInputStream.readByte(DataInputStream.java:248) at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:228) ... 12 more We are using Sun Java JDK 1.6.0_18 under Windows Server 2003 32-bit. Is it possible to work around the connection problems by tuning RMI related system properties?

    Read the article

  • Prepared transactions with Postgres 8.4.3 on CentOS

    - by peter
    I have set 'max_prepared_transactions' to 20 in the local postgres.config and yet the transaction fails with the following error trace (but only on Linux). Since in Windows the same code works seamlessly I am wandering if this isn't an issue of permission. What would be the solution? Thanks Peter 372300 [Atomikos:7] WARN atomikos - XA resource 'XADBMS': rollback for XID '3137332E3230332E3132362E3139302E746D30303030313030303037:3137332E3230332E3132362E3139302E746D31' raised -3: the XA resource detected an internal error org.postgresql.xa.PGXAException: Error rolling back prepared transaction at org.postgresql.xa.PGXAConnection.rollback(PGXAConnection.java:357) at com.atomikos.datasource.xa.XAResourceTransaction.rollback(XAResourceTransaction.java:873) at com.atomikos.icatch.imp.RollbackMessage.send(RollbackMessage.java:90) at com.atomikos.icatch.imp.PropagationMessage.submit(PropagationMessage.java:86) at com.atomikos.icatch.imp.Propagator$PropagatorThread.run(Propagator.java:62) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:651) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:676) at java.lang.Thread.run(Thread.java:595) Caused by: org.postgresql.util.PSQLException: ERROR: prepared transaction with identifier "1096044365_MTczLjIwMy4xMjYuMTkwLnRtMDAwMDEwMDAwNw==_MTczLjIwMy4xMjYuMTkwLnRtMQ==" does not exist at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2062) at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1795) at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:257) at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:479) at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:353) at org.postgresql.jdbc2.AbstractJdbc2Statement.executeUpdate(AbstractJdbc2Statement.java:299) at org.postgresql.xa.PGXAConnection.rollback(PGXAConnection.java:347)

    Read the article

  • when long polling, Why are my other requests taking so long?

    - by Pascal
    The client makes 2 concurrent requests. (1 which takes 60 seconds - long polling) and another which is NOT long polling - supposed to return right away. It does return right away when I'm not doing long polling. But as soon as I start doing long polling with the other thread, the other one takes forever to execute. Firebug shows that the request is waiting for 10-50 seconds. On the server, I profiled ALL requests from the moment the php script starts to the time it goes back to the client, and it shows that each one only took 300ms or less. This problem started about the same time I started doing long polling (with the other XHR requests). I'm using jquery for both requests. The server shows that it is under very light load. CPU and memory less then 2%. 8 processes running out of a pool of 15. (it doesn't seem to deviate much from that number 8, even when I run more ajax requests). I guess each process can run multiple ajax threads concurrently. I made sure to EXIT from all processes as soon as their done executing. I don't see how the process pool has run out, if there are still 7 unused processes listed under prstat -J. Also, the problem happens somewhat intermittently. Firefox should be able to handle 2 concurrent ajax requests. i dont get what the problem is.

    Read the article

  • SQL deadlock on delete then bulk insert

    - by StarLite
    I have an issue with a deadlock in SQL Server that I haven't been able to resolve. Basically I have a large number of concurrent connections (from many machines) that are executing transactions where they first delete a range of entries and then re-insert entries within the same range with a bulk insert. Essentially, the transaction looks like this BEGIN TRANSACTION T1 DELETE FROM [TableName] WITH( XLOCK HOLDLOCK ) WHERE [Id]=@Id AND [SubId]=@SubId INSERT BULK [TableName] ( [Id] Int , [SubId] Int , [Text] VarChar(max) COLLATE SQL_Latin1_General_CP1_CI_AS ) WITH(CHECK_CONSTRAINTS, FIRE_TRIGGERS) COMMIT TRANSACTION T1 The bulk insert only inserts items matching the Id and SubId of the deletion in the same transaction. Furthermore, these Id and SubId entries should never overlap. When I have enough concurrent transaction of this form, I start to see a significant number of deadlocks between these statements. I added the locking hints XLOCK HOLDLOCK to attempt to deal with the issue, but they don't seem to be helpling. The canonical deadlock graph for this error shows: Connection 1: Holds RangeX-X on PK_TableName Holds IX Page lock on the table Requesting X Page lock on the table Connection 2: Holds IX Page lock on the table Requests RangeX-X lock on the table What do I need to do in order to ensure that these deadlocks don't occur. I have been doing some reading on the RangeX-X locks and I'm not sure I fully understand what is going on with these. Do I have any options short of locking the entire table here?

    Read the article

  • XML parsing design using xmlpp and C++

    - by shagv
    I would like to use an xml format similar to the following: <CONFIG> <PROFILE NAME="foobar"> <PARAM ID="0" NAME="Foo" CLASS="BaseParam"/> <PARAM ID="2" NAME="Bar" CLASS="StrIntParam"> <VALUE TYPE="STRING">some String</VALUE> <VALUE TYPE="INT">1234</VALUE> </PARAM> </PROFILE> </CONFIG> CONFIG contains a list of PROFILEs which contain a list of PARAMs which themselves can be any structure (to be defined in the future). The idea was to define classes that parsed each PARAM type and to keep track of which class to use in the PARAM's CLASS attribute. In code I have a config class that manages the list of profiles and a profile class that manages the list of params. I would like the profile class to handle additional param types (that inherit BaseParam) without modification to the profile class (or at the very least with minimal modification). First of all, is this design viable? If so, what are some ways I could use different param classes and have their creation at run-time be automatic (the profile class sees the CLASS attribute and knows which type to create)?

    Read the article

  • Bluetooth connection. Problem with sony ericsson.

    - by Hugi
    I have bt client and server. Then i use method Connector.open, client connects to the port, but passed so that my server does not see them. Nokia for all normal, but with sony ericsson i have this problem. On bt adapter open one port (com 5). Listings Client /* * To change this template, choose Tools | Templates * and open the template in the editor. */ import java.util.Vector; import javax.bluetooth.*; import javax.microedition.midlet.*; import javax.microedition.lcdui.*; import javax.microedition.io.*; import java.io.*; /** * @author ????????????? */ public class Client extends MIDlet implements DiscoveryListener, CommandListener { private static Object lock=new Object(); private static Vector vecDevices=new Vector(); private ServiceRecord[] servRec = new ServiceRecord[INQUIRY_COMPLETED]; private Form form = new Form( "Search" ); private List voteList = new List( "Vote list", List.IMPLICIT ); private List vote = new List( "", List.EXCLUSIVE ); private RemoteDevice remoteDevice; private String connectionURL = null; protected int stopToken = 255; private Command select = null; public void startApp() { //view form Display.getDisplay(this).setCurrent(form); try { //device search print("Starting device inquiry..."); getAgent().startInquiry(DiscoveryAgent.GIAC, this); try { synchronized(lock){ lock.wait(); } }catch (InterruptedException e) { e.printStackTrace(); } //device count int deviceCount=vecDevices.size(); if(deviceCount <= 0) { print("No Devices Found ."); } else{ remoteDevice=(RemoteDevice)vecDevices.elementAt(0); print( "Server found" ); //create uuid UUID uuid = new UUID(0x1101); UUID uuids[] = new UUID[] { uuid }; //search service print( "Searching for service..." ); getAgent().searchServices(null,uuids,remoteDevice,this); } } catch( Exception e) { e.printStackTrace(); } } //if deivce discovered add to vecDevices public void deviceDiscovered(RemoteDevice btDevice, DeviceClass cod) { //add the device to the vector try { if(!vecDevices.contains(btDevice) && btDevice.getFriendlyName(true).equals("serverHugi")){ vecDevices.addElement(btDevice); } } catch( IOException e ) { } } public synchronized void servicesDiscovered(int transID, ServiceRecord[] servRecord) { //for each service create connection if( servRecord!=null && servRecord.length>0 ){ print( "Service found" ); connectionURL = servRecord[0].getConnectionURL(ServiceRecord.NOAUTHENTICATE_NOENCRYPT,false); //connectionURL = servRecord[0].getConnectionURL(ServiceRecord.AUTHENTICATE_NOENCRYPT,false); } if ( connectionURL != null ) { showVoteList(); } } public void serviceSearchCompleted(int transID, int respCode) { //print( "serviceSearchCompleted" ); synchronized(lock){ lock.notify(); } } //This callback method will be called when the device discovery is completed. public void inquiryCompleted(int discType) { synchronized(lock){ lock.notify(); } switch (discType) { case DiscoveryListener.INQUIRY_COMPLETED : print("INQUIRY_COMPLETED"); break; case DiscoveryListener.INQUIRY_TERMINATED : print("INQUIRY_TERMINATED"); break; case DiscoveryListener.INQUIRY_ERROR : print("INQUIRY_ERROR"); break; default : print("Unknown Response Code"); break; } } //add message at form public void print( String msg ) { form.append( msg ); form.append( "\n\n" ); } public void pauseApp() { } public void destroyApp(boolean unconditional) { } //get agent :))) private DiscoveryAgent getAgent() { try { return LocalDevice.getLocalDevice().getDiscoveryAgent(); } catch (BluetoothStateException e) { throw new Error(e.getMessage()); } } private synchronized String getMessage( final String send ) { StreamConnection stream = null; DataInputStream in = null; DataOutputStream out = null; String r = null; try { //open connection stream = (StreamConnection) Connector.open(connectionURL); in = stream.openDataInputStream(); out = stream.openDataOutputStream(); out.writeUTF( send ); out.flush(); r = in.readUTF(); print( r ); in.close(); out.close(); stream.close(); return r; } catch (IOException e) { } finally { if (stream != null) { try { stream.close(); } catch (IOException e) { } } return r; } } private synchronized void showVoteList() { String votes = getMessage( "c_getVotes" ); voteList.append( votes, null ); select = new Command( "Select", Command.OK, 4 ); voteList.addCommand( select ); voteList.setCommandListener( this ); Display.getDisplay(this).setCurrent(voteList); } private synchronized void showVote( int index ) { String title = getMessage( "c_getVote_"+index ); vote.setTitle( title ); vote.append( "Yes", null ); vote.append( "No", null ); vote.setCommandListener( this ); Display.getDisplay(this).setCurrent(vote); } public void commandAction( Command c, Displayable d ) { if ( c == select && d == voteList ) { int index = voteList.getSelectedIndex(); print( ""+index ); showVote( index ); } } } Use BlueCove in this program. Server /* * To change this template, choose Tools | Templates * and open the template in the editor. */ package javaapplication4; import java.io.*; import java.util.concurrent.locks.Lock; import java.util.concurrent.locks.ReentrantLock; import javax.bluetooth.*; import javax.microedition.io.*; import javaapplication4.Connect; /** * * @author ????????????? */ public class SampleSPPServer { protected static int endToken = 255; private static Lock lock=new ReentrantLock(); private static StreamConnection conn = null; private static StreamConnectionNotifier streamConnNotifier = null; private void startServer() throws IOException{ //Create a UUID for SPP UUID uuid = new UUID("1101", true); //Create the service url String connectionString = "btspp://localhost:" + uuid +";name=Sample SPP Server"; //open server url StreamConnectionNotifier streamConnNotifier = (StreamConnectionNotifier)Connector.open( connectionString ); while ( true ) { Connect ct = new Connect( streamConnNotifier.acceptAndOpen() ); ct.getMessage(); } } /** * @param args the command line arguments */ public static void main(String[] args) { //display local device address and name try { LocalDevice localDevice = LocalDevice.getLocalDevice(); localDevice.setDiscoverable(DiscoveryAgent.GIAC); System.out.println("Name: "+localDevice.getFriendlyName()); } catch( Throwable e ) { e.printStackTrace(); } SampleSPPServer sampleSPPServer=new SampleSPPServer(); try { //start server sampleSPPServer.startServer(); } catch( IOException e ) { e.printStackTrace(); } } } Connect /* * To change this template, choose Tools | Templates * and open the template in the editor. */ package javaapplication4; import java.io.*; import java.util.concurrent.locks.Lock; import java.util.concurrent.locks.ReentrantLock; import javax.bluetooth.*; import javax.microedition.io.*; /** * * @author ????????????? */ public class Connect { private static DataInputStream in = null; private static DataOutputStream out = null; private static StreamConnection connection = null; private static Lock lock=new ReentrantLock(); public Connect( StreamConnection conn ) { connection = conn; } public synchronized void getMessage( ) { Thread t = new Thread() { public void run() { try { in = connection.openDataInputStream(); out = connection.openDataOutputStream(); String r = in.readUTF(); System.out.println("read:" + r); if ( r.equals( "c_getVotes" ) ) { out.writeUTF( "vote1" ); out.flush(); } if ( r.equals( "c_getVote_0" ) ) { out.writeUTF( "Vote1" ); out.flush(); } out.close(); in.close(); } catch (Throwable e) { } finally { if (in != null) { try { in.close(); } catch (IOException e) { } } try { connection.close(); } catch( IOException e ) { } } } }; t.start(); } }

    Read the article

  • Synchronizing ASP.NET MVC action methods with ReaderWriterLockSlim

    - by James D
    Any obvious issues/problems/gotchas with synchronizing access (in an ASP.NET MVC blogging engine) to a shared object model (NHibernate, but it could be anything) at the Controller/Action level via ReaderWriterLockSlim? (Assume the object model is very large and expensive to build per-request, so we need to share it among requests.) Here's how a typical "Read Post" action would look. Enter the read lock, do some work, exit the read lock. public ActionResult ReadPost(int id) { // ReaderWriterLockSlim allows multiple concurrent writes; this method // only blocks in the unlikely event that some other client is currently // writing to the model, which would only happen if a comment were being // submitted or a new post were being saved. _lock.EnterReadLock(); try { // Access the model, fetch the post with specificied id // Pseudocode, etc. Post p = TheObjectModel.GetPostByID(id); ActionResult ar = View(p); return ar; } finally { // Under all code paths, we must release the read lock _lock.ExitReadLock(); } } Meanwhile, if a user submits a comment or an author authors a new post, they're going to need write access to the model, which is done roughly like so: [AcceptVerbs(HttpVerbs.Post)] public ActionResult SaveComment(/* some posted data */) { // try/finally omitted for brevity _lock.EnterWriteLock(); // Save the comment to the DB, update the model to include the comment, etc. _lock.ExitWriteLock(); } Of course, this could also be done by tagging those action methods with some sort of "synchronized" attribute... but however you do it, my question is is this a bad idea? ps. ReaderWriterLockSlim is optimized for multiple concurrent reads, and only blocks if the write lock is held. Since writes are so infrequent (1000s or 10,000s or 100,000s of reads for every 1 write), and since they're of such a short duration, the effect is that the model is synchronized , and almost nobody ever locks, and if they do, it's not for very long.

    Read the article

  • Apache with JBOSS using AJP (mod_jk) giving spikes in thread count.

    - by Beginner
    We used Apache with JBOSS for hosting our Application, but we found some issues related to thread handling of mod_jk. Our website comes under low traffic websites and has maximum 200-300 concurrent users during our website's peak activity time. As the traffic grows (not in terms of concurrent users, but in terms of cumulative requests which came to our server), the server stopped serving requests for long, although it didn't crash but could not serve the request till 20 mins. The JBOSS server console showed that 350 thread were busy on both servers although there was enough free memory say, more than 1-1.5 GB (2 servers for JBOSS were used which were 64 bits, 4 GB RAM allocated for JBOSS) In order to check the problem we were using JBOSS and Apache Web Consoles, and we were seeing that the thread were showing in S state for as long as minutes although our pages take around 4-5 seconds to be served. We took the thread dump and found that the threads were mostly in WAITING state which means that they were waiting indefinitely. These threads were not of our Application Classes but of AJP 8009 port. Could somebody help me in this, as somebody else might also got this issue and solved it somehow. In case any more information is required then let me know. Also is mod_proxy better than using mod_jk, or there are some other problems with mod_proxy which can be fatal for me if I switch to mod__proxy? The versions I used are as follows: Apache 2.0.52 JBOSS: 4.2.2 MOD_JK: 1.2.20 JDK: 1.6 Operating System: RHEL 4 Thanks for the help.

    Read the article

  • Hazelcast Distributed Executor Service KeyOwner

    - by János Veres
    I have problem understanding the concept of Hazelcast Distributed Execution. It is said to be able to perform the execution on the owner instance of a specific key. From Documentation: <T> Future<T> submitToKeyOwner(Callable<T> task, Object key) Submits task to owner of the specified key and returns a Future representing that task. Parameters: task - task key - key Returns: a Future representing pending completion of the task I believe that I'm not alone to have a cluster built with multiple maps which might actually use the same key for different purposes, holding different objects (e.g. something along the following setup): IMap<String, ObjectTypeA> firstMap = HazelcastInstance.getMap("firstMap"); IMap<String, ObjectTypeA_AppendixClass> secondMap = HazelcastInstance.getMap("secondMap"); To me it seems quite confusing what documentation says about the owner of a key. My real frustration is that I don't know WHICH - in which map - key does it refer to? The documentation also gives a "demo" of this approach: import com.hazelcast.core.Member; import com.hazelcast.core.Hazelcast; import com.hazelcast.core.IExecutorService; import java.util.concurrent.Callable; import java.util.concurrent.Future; import java.util.Set; import com.hazelcast.config.Config; public void echoOnTheMemberOwningTheKey(String input, Object key) throws Exception { Callable<String> task = new Echo(input); HazelcastInstance hz = Hazelcast.newHazelcastInstance(); IExecutorService executorService = hz.getExecutorService("default"); Future<String> future = executorService.submitToKeyOwner(task, key); String echoResult = future.get(); } Here's a link to the documentation site: Hazelcast MultiHTML Documentation 3.0 - Distributed Execution Did any of you guys figure out in the past what key does it want?

    Read the article

  • How to properly close a UDT server in Netty 4

    - by Steffen
    I'm trying to close my UDT server (Netty 4.0.5.Final) with shutDownGracefully() and reopen it on the same port. Unfortunately, I always get the socket exception below although it waits until the future has completed. I also added the socket option SO_REUSEADDR. What is the proper way to do this? Exception in thread "main" com.barchart.udt.ExceptionUDT: UDT Error : 5011 : another socket is already listening on the same UDP port : listen0:listen [id: 0x323d3939] at com.barchart.udt.SocketUDT.listen0(Native Method) at com.barchart.udt.SocketUDT.listen(SocketUDT.java:1136) at com.barchart.udt.net.NetServerSocketUDT.bind(NetServerSocketUDT.java:66) at io.netty.channel.udt.nio.NioUdtAcceptorChannel.doBind(NioUdtAcceptorChannel.java:71) at io.netty.channel.AbstractChannel$AbstractUnsafe.bind(AbstractChannel.java:471) at io.netty.channel.DefaultChannelPipeline$HeadHandler.bind(DefaultChannelPipeline.java:1006) at io.netty.channel.DefaultChannelHandlerContext.invokeBind(DefaultChannelHandlerContext.java:504) at io.netty.channel.DefaultChannelHandlerContext.bind(DefaultChannelHandlerContext.java:487) at io.netty.channel.ChannelDuplexHandler.bind(ChannelDuplexHandler.java:38) at io.netty.handler.logging.LoggingHandler.bind(LoggingHandler.java:254) at io.netty.channel.DefaultChannelHandlerContext.invokeBind(DefaultChannelHandlerContext.java:504) at io.netty.channel.DefaultChannelHandlerContext.bind(DefaultChannelHandlerContext.java:487) at io.netty.channel.DefaultChannelPipeline.bind(DefaultChannelPipeline.java:848) at io.netty.channel.AbstractChannel.bind(AbstractChannel.java:193) at io.netty.bootstrap.AbstractBootstrap$2.run(AbstractBootstrap.java:321) at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:354) at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:366) at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:101) at java.lang.Thread.run(Thread.java:724) A small test program demonstration the problem: public class MsgEchoServer { public static class MsgEchoServerHandler extends ChannelInboundHandlerAdapter { } public void run() throws Exception { final ThreadFactory acceptFactory = new UtilThreadFactory("accept"); final ThreadFactory connectFactory = new UtilThreadFactory("connect"); final NioEventLoopGroup acceptGroup = new NioEventLoopGroup(1, acceptFactory, NioUdtProvider.MESSAGE_PROVIDER); final NioEventLoopGroup connectGroup = new NioEventLoopGroup(1, connectFactory, NioUdtProvider.MESSAGE_PROVIDER); try { final ServerBootstrap boot = new ServerBootstrap(); boot.group(acceptGroup, connectGroup) .channelFactory(NioUdtProvider.MESSAGE_ACCEPTOR) .option(ChannelOption.SO_BACKLOG, 10) .option(ChannelOption.SO_REUSEADDR, true) .handler(new LoggingHandler(LogLevel.INFO)) .childHandler(new ChannelInitializer<UdtChannel>() { @Override public void initChannel(final UdtChannel ch) throws Exception { ch.pipeline().addLast(new MsgEchoServerHandler()); } }); final ChannelFuture future = boot.bind(1234).sync(); } finally { acceptGroup.shutdownGracefully().syncUninterruptibly(); connectGroup.shutdownGracefully().syncUninterruptibly(); } new MsgEchoServer().run(); } public static void main(final String[] args) throws Exception { new MsgEchoServer().run(); } }

    Read the article

  • Understanding Java Wait and Notify methods

    - by Maddy
    Hello all: I have a following program: import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; public class SimpleWaitNotify implements Runnable { final static Object obj = new Object(); static boolean value = true; public synchronized void flag() { System.out.println("Before Wait"); try { obj.wait(); } catch (InterruptedException e) { System.out.println("Thread interrupted"); } System.out.println("After Being Notified"); } public synchronized void unflag() { System.out.println("Before Notify All"); obj.notifyAll(); System.out.println("After Notify All Method Call"); } public void run() { if (value) { flag(); } else { unflag(); } } public static void main(String[] args) throws InterruptedException { ExecutorService pool = Executors.newFixedThreadPool(4); SimpleWaitNotify sWait = new SimpleWaitNotify(); pool.execute(sWait); SimpleWaitNotify.value = false; SimpleWaitNotify sNotify = new SimpleWaitNotify(); pool.execute(sNotify); pool.shutdown(); } } When I wait on obj, I get the following exception Exception in thread "pool-1-thread-1" java.lang.IllegalMonitorStateException: current thread not owner for each of the two threads. But if I use SimpleWaitNotify's monitor then the program execution is suspended. In other words, I think it suspends current execution thread and in turn the executor. Any help towards understanding what's going on would be duly appreciated. This is an area1 where the theory and javadoc seem straightforward, and since there aren't many examples, conceptually left a big gap in me.

    Read the article

  • how to restart a Thread?

    - by wizztjh
    It is a RMI Server object , so many sethumanActivity() might be run , how do i make sure the previous changeToFalse thread will be stop or halt before the new changeToFalse run? t. interrupt ? Basically when sethumanActivity() is invoke , the humanActivity will be set to true , but a thread will be run to set it back to false. But I am thinking for how to disable or kill the thread when another sethumanActivity() invoked? public class VitaminDEngine implements VitaminD { public boolean humanActivity = false; changeToFalse cf = new changeToFalse(); Thread t = new Thread(cf); private class changeToFalse implements Runnable{ @Override public void run() { try { Thread.sleep(4000); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } humanActivity = false; } } @Override public void sethumanActivity() throws RemoteException { // TODO Auto-generated method stub humanActivity = true; t.start(); } public boolean gethumanActivity() throws RemoteException { // TODO Auto-generated method stub return humanActivity; } } Edited after the help of SOer package smartOfficeJava; import java.rmi.RemoteException; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; public class VitaminDEngine implements VitaminD { public volatile boolean humanActivity = false; changeToFalse cf = new changeToFalse(); ExecutorService service = Executors.newSingleThreadExecutor(); private class changeToFalse implements Runnable{ @Override public void run() { try { Thread.sleep(4000); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } humanActivity = false; } } @Override public synchronized void sethumanActivity() throws RemoteException { humanActivity = true; service.submit(cf); } public synchronized boolean gethumanActivity() throws RemoteException { return humanActivity; } }

    Read the article

  • volatile keyword seems to be useless?

    - by Finbarr
    import java.util.concurrent.CountDownLatch; import java.util.concurrent.atomic.AtomicInteger; public class Main implements Runnable { private final CountDownLatch cdl1 = new CountDownLatch(NUM_THREADS); private volatile int bar = 0; private AtomicInteger count = new AtomicInteger(0); private static final int NUM_THREADS = 25; public static void main(String[] args) { Main main = new Main(); for(int i = 0; i < NUM_THREADS; i++) new Thread(main).start(); } public void run() { int i = count.incrementAndGet(); cdl1.countDown(); try { cdl1.await(); } catch (InterruptedException e1) { e1.printStackTrace(); } bar = i; if(bar != i) System.out.println("Bar not equal to i"); else System.out.println("Bar equal to i"); } } Each Thread enters the run method and acquires a unique, thread confined, int variable i by getting a value from the AtomicInteger called count. Each Thread then awaits the CountDownLatch called cdl1 (when the last Thread reaches the latch, all Threads are released). When the latch is released each thread attempts to assign their confined i value to the shared, volatile, int called bar. I would expect every Thread except one to print out "Bar not equal to i", but every Thread prints "Bar equal to i". Eh, wtf does volatile actually do if not this?

    Read the article

  • Create new or update existing entity at one go with JPA

    - by Alex R
    A have a JPA entity that has timestamp field and is distinguished by a complex identifier field. What I need is to update timestamp in an entity that has already been stored, otherwise create and store new entity with the current timestamp. As it turns out the task is not as simple as it seems from the first sight. The problem is that in concurrent environment I get nasty "Unique index or primary key violation" exception. Here's my code: // Load existing entity, if any. Entity e = entityManager.find(Entity.class, id); if (e == null) { // Could not find entity with the specified id in the database, so create new one. e = entityManager.merge(new Entity(id)); } // Set current time... e.setTimestamp(new Date()); // ...and finally save entity. entityManager.flush(); Please note that in this example entity identifier is not generated on insert, it is known in advance. When two or more of threads run this block of code in parallel, they may simultaneously get null from entityManager.find(Entity.class, id) method call, so they will attempt to save two or more entities at the same time, with the same identifier resulting in error. I think that there are few solutions to the problem. Sure I could synchronize this code block with a global lock to prevent concurrent access to the database, but would it be the most efficient way? Some databases support very handy MERGE statement that updates existing or creates new row if none exists. But I doubt that OpenJPA (JPA implementation of my choice) supports it. Event if JPA does not support SQL MERGE, I can always fall back to plain old JDBC and do whatever I want with the database. But I don't want to leave comfortable API and mess with hairy JDBC+SQL combination. There is a magic trick to fix it using standard JPA API only, but I don't know it yet. Please help.

    Read the article

  • Client-server synchronization pattern / algorithm?

    - by tm_lv
    I have a feeling that there must be client-server synchronization patterns out there. But i totally failed to google up one. Situation is quite simple - server is the central node, that multiple clients connect to and manipulate same data. Data can be split in atoms, in case of conflict, whatever is on server, has priority (to avoid getting user into conflict solving). Partial synchronization is preferred due to potentially large amounts of data. Are there any patterns / good practices for such situation, or if you don't know of any - what would be your approach? Below is how i now think to solve it: Parallel to data, a modification journal will be held, having all transactions timestamped. When client connects, it receives all changes since last check, in consolidated form (server goes through lists and removes additions that are followed by deletions, merges updates for each atom, etc.). Et voila, we are up to date. Alternative would be keeping modification date for each record, and instead of performing data deletes, just mark them as deleted. Any thoughts?

    Read the article

  • What are some of the core principles needed to master Multi threading using Delphi?

    - by Gary Becks
    I am kind of new to programming in general (about 8 months with on and off in delphi and a little python here and there) and I am in the process of buying some books. I am interested in learning about concurrent programming and building multi threaded apps using Delphi. Whenever I do a search for "multithreading delphi" or "delphi multithreading tutorial" I seem to get conflicting results as some of the stuff is about using certain libraries (omnithread library) and other stuff seems to be more geared towards programmers with more experience. I have studied quite a few books on delphi and for the most part they seem to kind of skim the surface and not really go into depth on the subject. I have a friend who is a programmer (he uses c++) who recommends I learn what is actually going on with the underlying system when using threads as opposed to jumping into how to actually implement them in my programs first. On amazon.com there are quite a few books on concurrent programming but none of them seem to be made with Delphi in mind. Basically I need to know what are the main things I should be focused on learning before jumping into using threads, if I can/should attempt to learn them using books that are not specifically aimed at delphi developers (don't want to confuse myself reading books with a bunch of code examples in other languages right now) and if there are any reliable resources/books on the subject that anyone here could recommend. Thanks in advance.

    Read the article

  • Writing to a file in a servlet

    - by ankur verma
    I am working in a servlet and has this code : public void doPost(blah blah){ response.setContentType("text/html"); String datasent = request.getParameter("dataSent"); System.out.println(datasent); try{ FileWriter writer = new FileWriter("C:/xyz.txt"); writer.write("hello"); System.out.println("I wrote"); }catch(Exception ex){ ex.printStackTrace(); } response.getWriter().write("I am from server"); } But everytime it is throwing an error saying Access Denied.. Even when there is no lock on that file and there is no file whose name is C:/xyz.txt what should I do? ;( java.io.FileNotFoundException: C:\xyz.txt (Access is denied) at java.io.FileOutputStream.open(Native Method) at java.io.FileOutputStream.<init>(FileOutputStream.java:212) at java.io.FileOutputStream.<init>(FileOutputStream.java:104) at java.io.FileWriter.<init>(FileWriter.java:63) at test.TestServlet.doPost(TestServlet.java:49) at javax.servlet.http.HttpServlet.service(HttpServlet.java:641) at javax.servlet.http.HttpServlet.service(HttpServlet.java:722) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:306) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:108) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:558) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:379) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:243) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:259) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:237) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:281) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603) at java.lang.Thread.run(Thread.java:722)

    Read the article

  • CodePlex Daily Summary for Monday, November 26, 2012

    CodePlex Daily Summary for Monday, November 26, 2012Popular ReleasesRedmine Reports: Redmine Reports V 1.0.7: added new sample report added new DateRange feature for report generation (see issue Tracker ID 15372) updated to latest MySql (6.6.4.0)sb0t v.5: sb0t 5.00 alpha 4: First public alpha release. Don't be surprised if it crashes. :)datajs - JavaScript Library for data-centric web applications: datajs version 1.1.0: datajs is a cross-browser and UI agnostic JavaScript library that enables data-centric web applications with the following features: OData client that enables CRUD operations including batching and metadata support using both ATOM and JSON payloads. Single store abstraction that provides a common API on top of HTML5 local storage technologies. Data cache component that allows reading data ranges from a collection and storing them locally to reduce the number of network requests. Changes...VFPX: Code Analyst 1.0.3: Code Analyst 1.0.3 addresses a bug discovered with FoxCodePlus where the initialization code does not properly recognize the location of the folder as well as some of the open issues in the Issue Tracker.Team Foundation Server Administration Tool: 2.2: TFS Administration Tool 2.2 supports the Team Foundation Server 2012 Object Model. Visual Studio 2012 or Team Explorer 2012 must be installed before you can install this tool. You can download and install Team Explorer 2012 from http://aka.ms/TeamExplorer2012. There are no functional changes between the previous release (2.1) and this release.XrmServiceToolkit - A CRM 2011 JavaScript Library: XrmServiceToolkit 1.3.1: Version: 1.3.1 Date: November, 2012 Dependency: JSON2, jQuery (latest or 1.7.2 above) New Feature - A change of logic to increase peroformance when returning large number of records New Function - XrmServiceToolkit.Soap.QueryAll: Return all available records by query options (>5k+) New Fix - XrmServiceToolkit.Rest.RetrieveMultiple not returning records more than 50 New Fix - XrmServiceToolkit.Soap.Business error when refering number fields like (int, double, float) New ...Coding Guidelines for C# 3.0, C# 4.0 and C# 5.0: Coding Guidelines for CSharp 3.0, 4.0 and 5.0: See Change History for a detailed list of modifications.Math.NET Numerics: Math.NET Numerics v2.3.0: Portable Library Build: Adds support for WP8 (.Net 4.0 and higher, SL5, WP8 and .NET for Windows Store apps) New: portable build also for F# extensions (.Net 4.5, SL5 and .NET for Windows Store apps) NuGet: portable builds are now included in the main packages, no more need for special portable packages Linear Algebra: Continued major storage rework, in this release focusing on vectors (previous release was on matrices) Thin QR decomposition (in addition to existing full QR) Static Cr...ExtJS based ASP.NET 2.0 Controls: FineUI v3.2.1: +2012-11-25 v3.2.1 +????????。 -MenuCheckBox?CheckedChanged??????,??????????。 -???????window.IDS??????????????。 -?????(??TabCollection,ControlBaseCollection)???,????????????????。 +Grid??。 -??SelectAllRows??。 -??PageItems??,?????????????,?????、??、?????。 -????grid/gridpageitems.aspx、grid/gridpageitemsrowexpander.aspx、grid/gridpageitems_pagesize.aspx。 -???????????????????。 -??ExpandAllRowExpanders??,?????????????????(grid/gridrowexpanderexpandall2.aspx)。 -??????ExpandRowExpande...VidCoder: 1.4.9 Beta: Updated HandBrake core to SVN 5079. Fixed crashes when encoding DVDs with title gaps.ZXing.Net: ZXing.Net 0.10.0.0: On the way to a release 1.0 the API should be stable now with this version. sync with rev. 2521 of the java version windows phone 8 assemblies improvements and fixesCharmBar: Windows 8 Charm Bar for Windows 7: Windows 8 Charm Bar for Windows 7BlackJumboDog: Ver5.7.3: 2012.11.24 Ver5.7.3 (1)SMTP???????、?????????、??????????????????????? (2)?????????、?????????????????????????? (3)DNS???????CNAME????CNAME????????????????? (4)DNS????????????TTL???????? (5)???????????????????????、?????????????????? (6)???????????????????????????????Liberty: v3.4.3.0 Release 23rd November 2012: Change Log -Added -H4 A dialog which gives further instructions when attempting to open a "Halo 4 Data" file -H4 Added a short note to the weapon editor stating that dropping your weapons will cap their ammo -Reach Edit the world's gravity -Reach Fine invincibility controls in the object editor -Reach Edit object velocity -Reach Change the teams of AI bipeds and vehicles -Reach Enable/disable fall damage on the biped editor screen -Reach Make AIs deaf and/or blind in the objec...Umbraco CMS: Umbraco 4.11.0: NugetNuGet BlogRead the release blog post for 4.11.0. Whats new50 bugfixes (see the issue tracker for a complete list) Read the documentation for the MVC bits. Breaking changesGetPropertyValue now returns an object, not a string (only affects upgrades from 4.10.x to 4.11.0) NoteIf you need Courier use the release candidate (as of build 26). The code editor has been greatly improved, but is sometimes problematic in Internet Explorer 9 and lower. Previously it was just disabled for IE and...Audio Pitch & Shift: Audio Pitch And Shift 5.1.0.3: Fixed supported files list on open dialog (added .pls and .m3u) Impulse Media Player splash message (can be disabled anyway)WiX Toolset: WiX v3.7 RC: WiX v3.7 RC (3.7.1119.0) provides feature complete Bundle update and reference tracking plus several bug fixes. For more information see Rob's blog post about the release: http://robmensching.com/blog/posts/2012/11/20/WiX-v3.7-Release-Candidate-availablePicturethrill: Version 2.11.20.0: Fixed up Bing image provider on Windows 8Excel AddIn to reset the last worksheet cell: XSFormatCleaner.xla: Modified the commandbar code to use CommandBar IDs instead of English names.Json.NET: Json.NET 4.5 Release 11: New feature - Added ITraceWriter, MemoryTraceWriter, DiagnosticsTraceWriter New feature - Added StringEscapeHandling with options to escape HTML and non-ASCII characters New feature - Added non-generic JToken.ToObject methods New feature - Deserialize ISet<T> properties as HashSet<T> New feature - Added implicit conversions for Uri, TimeSpan, Guid New feature - Missing byte, char, Guid, TimeSpan and Uri explicit conversion operators added to JToken New feature - Special case...New ProjectsAirlocker: Airlocker is a lightweight yet effective backup software. Right-click your folder, select "Send To -> Airlocker", and that's all! Next time you do it, only new & changed files will be copied.Architecture Lab: Domain as XML: Domain as XML - Driven Development: Visual Studio Code SamplesBase de datos 2 Farmacia distribuida: This is my summaryBullfrog project 2k11: This project was our entry for the XNA challenge 2011 at Games Fleadh. This is currently being used for a college project.CedarLogic SharePoint Utilities and Extensions: Various utilities, tools, features that provide cross cutting capabilities in support of Windows SharePoint Services 3.0 and Microsoft Office SharePoint Server 2007.Concurrent Extensions Library (CEL): Concurrent Extensions Library (CEL) provides functionality and implementations commonly useful in concurrent programming. CookieChipper - Tasty treats!: Explore your IE cookie cache dispaying forensic information, lock favorite cookies, delete all unlocked, search, manage, enjoy!CqRS Event Sourcing Sample: CqRS SampleCrivo de Erastóteles: Simples programa que devolve à você todos os números primos entre 1 e 1 bilhão em um arquivo de saída chamado "primos.txt" Simply program returns all prime numbers from 1 to 1 bi into a "primos.txt" out file.DonNicky.Common: A set of helpers for everyday coding: extensions for common purpose classes like Type, IEnumerable or Assembly, reflection routines, xml parsing and validation.DotNetDevNet iPhone App: Now you can find out what meetings are being held at DotNetDevNet through your iPhone. Information on the meeting and the speakersEuro for Windows XP: A simple tool and sample to change Estonian currency from Estonian Krone (kr) to Euro (€). Applies to all versions of Windows and from .NET 2.0 which is default build. The sample creates a custom locale and updates existing users through Registry.Floridum: Project for a XML Database.FsSignals: FsSignals is a push reactive library. Fuse8.CMF: Free Content Management System based on Microsoft ASP.NET MVC 3Fuse8.DF.Practicies: Domain Framework Best practicesFuse8.GlobalisationFramework: GlobalizationHatena Netfx Library: .NET Library for Hatena Services.Ideopuzzle: A puzzle gameinohigo: a programming language that was developed by inohiro.jasBetaApplication: Beta place for the JAS-applicationJasmine - Community Management Infrastructure: "Jasmine" is a XML based Community Management Infrastructure.Jupiter Toolkit: Jupiter Toolkit was a temporary name used for WinRT XAML Toolkit. If you clicked a link to get here - replace jupitertoolkit with winrtxamltoolkit in the URL.Kiwi Repo: Il modo più semplice per creare e gestire i tuoi repository cydia su windowsKnak: .NET APIs for CLR Type Mapping and Micro-ORM. Fast and intuitive, convention based, delivered in small C# source files.Micajah Mindtouch Deki Wiki Copier: Small C# application to move data between 2 Deki Wiki installs or, more importantly, from a wik.is account to a locally installed systemmisframework: misframeworkMulyareksa Jayasakti Accounting: Sistem Informasi Akunting Penjualan Jasa PT Mulyareksa Jayasakti SemarangMutualGuaranteeOnlineServices: MutualGuaranteeOnlineServicesMySQL PowerShell Extensions: MySQL PowerShell Extensions Provides a set of PowerShell Cmdlets to manipulate remote or local MySQL Database Server.Old Book Transaction: Website trao d?i sách cu.OneFineDay: ???Paymill Wrapper .NET: Paymill Wrapper. NET is an API for easy integration for recurring billings and payments online through the product https://www.paymill.comPoliceHealth: Police Health SystemRbac_Eshoping: Rbac Std ProjectRhombus: Rhombus is a suite of applications to make it easier for small software teams to document what they and others are doing with a minimum of effort. It is developed on the .NET 4.0 framework, primarily in C# and ASP.NET.Rollout Sharepoint Solutions - ROSS: ROSS performs the following actions: - Delete sitecollection and restart services - 'Get Latest Version' from SourceSafe - Rebuild Solution - Install all wsp solutions - Create SiteCollections - Check for build en provisioning errors - Send email to developers if errors occurredRooBooks: RooBooks - Books management tool for students and such. (circa 2004)SEI_Parkour: “Project ParkOUR” is the codename for the product being developed by members of the Software Engineering Incorporated team.Simple Memory: A simple Memory. You can define the dimension x*y. Also there are two playing modes possible. - Pairs with the same cards (classical memory) - Pairs with different cards (find the same meaning)Simples: A dot-net-a-ma-bob eco-system designed to be 'simples' to use.Slatebox.js: Real-time mind-mapping and concept drawing.Sychevs: ?????????? ?????Tambourine.NUnit: Provides pivot report creating from NUnit combinatorial test result xml files. Also supports viewing of pivot data and its exporting to xlsx.TheAssassin's OpenSource Software: Open source software for everyone's use. Mostly written in Python 3 (3.2, 3.3).Titan: a lightweight object-relational mapping framework TT: Awesome TT appUkázkové projekty: Obsahuje ukázkové projekty uživatele TenCoKaciStromy.Unified Cloud API: This API aims to provide a single interface for different cloud-based services and their corresponding providers.VolgaTransTelecomClient: VolgaTransTelecomClient makes it easier for clients of "Volga TransTelecom" company to get info about account. It's developed in C#.Windows Phone Shortcuts: This a windows phone app project. Shortcuts for Bluetooth, Wi-Fi, Cellular, Airplane Mode from the Start Screen.WPFResumeVideo: Play video on any computer, and resume where you left offWyvern's Depot: Personal code repository.?????????: ??????????,???。

    Read the article

  • Apache2 benchmarks - very poor performance

    - by andrzejp
    I have two servers on which I test the configuration of apache2. The first server: 4GB of RAM, AMD Athlon (tm) 64 X2 Dual Core Processor 5600 + Apache 2.2.3, mod_php, mpm prefork: Settings: Timeout 100 KeepAlive On MaxKeepAliveRequests 150 KeepAliveTimeout 4 <IfModule Mpm_prefork_module> StartServers 7 MinSpareServers 15 MaxSpareServers 30 MaxClients 250 MaxRequestsPerChild 2000 </ IfModule> Compiled in modules: core.c mod_log_config.c mod_logio.c prefork.c http_core.c mod_so.c Second server: 8GB of RAM, Intel (R) Core (TM) i7 CPU [email protected] Apache 2.2.9, **fcgid, mpm worker, suexec** PHP scripts are running via fcgi-wrapper Settings: Timeout 100 KeepAlive On MaxKeepAliveRequests 100 KeepAliveTimeout 4 <IfModule Mpm_worker_module> StartServers 10 MaxClients 200 MinSpareThreads 25 MaxSpareThreads 75 ThreadsPerChild 25 MaxRequestsPerChild 1000 </ IfModule> Compiled in modules: core.c mod_log_config.c mod_logio.c worker.c http_core.c mod_so.c The following test results, which are very strange! New server (dynamic content - php via fcgid+suexec): Server Software: Apache/2.2.9 Server Hostname: XXXXXXXX Server Port: 80 Document Path: XXXXXXX Document Length: 179512 bytes Concurrency Level: 10 Time taken for tests: 0.26276 seconds Complete requests: 1000 Failed requests: 0 Total transferred: 179935000 bytes HTML transferred: 179512000 bytes Requests per second: 38.06 Transfer rate: 6847.88 kb/s received Connnection Times (ms) min avg max Connect: 2 4 54 Processing: 161 257 449 Total: 163 261 503 Old server (dynamic content - mod_php): Server Software: Apache/2.2.3 Server Hostname: XXXXXX Server Port: 80 Document Path: XXXXXX Document Length: 187537 bytes Concurrency Level: 10 Time taken for tests: 173.073 seconds Complete requests: 1000 Failed requests: 22 (Connect: 0, Length: 22, Exceptions: 0) Total transferred: 188003372 bytes HTML transferred: 187546372 bytes Requests per second: 5777.91 Transfer rate: 1086267.40 kb/s received Connnection Times (ms) min avg max Connect: 3 3 28 Processing: 298 1724 26615 Total: 301 1727 26643 Old server: Static content (jpg file) Server Software: Apache/2.2.3 Server Hostname: xxxxxxxxx Server Port: 80 Document Path: /images/top2.gif Document Length: 40486 bytes Concurrency Level: 100 Time taken for tests: 3.558 seconds Complete requests: 1000 Failed requests: 0 Write errors: 0 Total transferred: 40864400 bytes HTML transferred: 40557482 bytes Requests per second: 281.09 [#/sec] (mean) Time per request: 355.753 [ms] (mean) Time per request: 3.558 [ms] (mean, across all concurrent requests) Transfer rate: 11217.51 [Kbytes/sec] received Connection Times (ms) min mean[+/-sd] median max Connect: 3 11 4.5 12 23 Processing: 40 329 61.4 339 1009 Waiting: 6 282 55.2 293 737 Total: 43 340 63.0 351 1020 New server - static content (jpg file) Server Software: Apache/2.2.9 Server Hostname: XXXXX Server Port: 80 Document Path: /images/top2.gif Document Length: 40486 bytes Concurrency Level: 100 Time taken for tests: 3.571531 seconds Complete requests: 1000 Failed requests: 0 Write errors: 0 Total transferred: 41282792 bytes HTML transferred: 41030080 bytes Requests per second: 279.99 [#/sec] (mean) Time per request: 357.153 [ms] (mean) Time per request: 3.572 [ms] (mean, across all concurrent requests) Transfer rate: 11287.88 [Kbytes/sec] received Connection Times (ms) min mean[+/-sd] median max Connect: 2 63 24.8 66 119 Processing: 124 278 31.8 282 391 Waiting: 3 70 28.5 66 164 Total: 126 341 35.9 350 443 I noticed that in the apache error.log is a lot of entries: [notice] mod_fcgid: call /www/XXXXX/public_html/forum/index.php with wrapper /www/php-fcgi-scripts/XXXXXX/php-fcgi-starter What I have omitted, or do not understand? Such a difference in requests per second? Is it possible? What could be the cause?

    Read the article

  • Linksys SRW248g4p and hp procurves

    - by Garfield81
    We've got about 3 procurves linked up with about 5 linksys srw248g4p. Pinging between the Procurves I get ping time between 1-2 ms and pinging between the linksys the ping time are averaging 40 ms. I have evening tried pinging between two linksys switches that are connected to each other directly using the GB ports. There have no modification done to the switches and the firmware seems to be uptodate. Any suggestions would be appreciated.

    Read the article

  • Windows 7: Creating a password-protected task (NOT a programming question)

    - by Matthias
    Hello, I would like to configure a task like "child control software", so it would hibernate the pc at certain times. Is it possible to prevent modification (here: pausing) of a task through requiring the entering of the admin password to modify, EVEN THOUGH the currently-logged-in (and only) user is the admin account itself? (Do you know of any child control software that does NOT require an additional account yet is able to hibernate the system at certain times?) Thanks a lot! Matthias

    Read the article

  • load balancing in Tomcat

    - by Alvin
    Hi All, I want to implement the load balancing in tomcat 6.0 so that we can create more than one instance of a tomcat and when any of the instance is down then other instance will run our application. so that our application will never be down even when the large number of concurrent request comes. But i have no idea to implement it. Please give your precious suggestions.

    Read the article

< Previous Page | 21 22 23 24 25 26 27 28 29 30 31 32  | Next Page >