java-ee

问题 If I do not specify the following in my web.xml file: <session-config> <session-timeout>10</session-timeout> </session-config> What will be my default session timeout? (I am running Tomcat 6.0) 回答1: If you're using Tomcat, it's 30 minutes. You can read more about it here. 回答2: You can also set this in code, for a specific session using the HttpSession setMaxInactiveInterval API: Specifies the time, in seconds, between client requests before the servlet container will invalidate this session.

问题 I have a stateless bean with bean-managed transactions, and a method like this: @Stateless @TransactionManagement(TransactionManagementType.BEAN) public class ... { @Resource private UserTransaction ut; @EJB private OtherStatelessBeanLocal other; public void invokeSomeMethods() ut.begin(); ... // invoke other bean's methods here. other.method(); ... ut.commit(); } } So how does the UserTransaction propagate to the OtherStatelessBeanLocal bean? 回答1: The UserTransaction object is an object

问题 I have a JAX-RS resource, which gets its paramaters as a JSON string like this: http://some.test/aresource?query={"paramA":"value1", "paramB":"value2"} The reason to use JSON here, is that the query object can be quite complex in real use cases. I'd like to convert the JSON string to a Java object, dto in the example: @GET @Produces("text/plain") public String getIt(@QueryParam("query") DataTransferObject dto ) { ... } Does JAX-RS support such a conversion from JSON passed as a query param to

问题 I have EAR with an application and I need to extend this app with my own code that is packaged as a WAR. Is there a maven plugin that can help me with putting the WAR inside the EAR? The manual procedure is to put WAR inside EAR and add module to application.xml. I would like to automate that. EDIT: small clarification - the WAR project is using maven but for EAR I have only the binary file nothing more. 回答1: I'd create a new module that has <packaging>ear</packaging> . In the dependencies

问题 Java EE application servers provide all the features of tomcat, so why use tomcat (instead of glassfish for example as it is the official one)? Especially when Java EE features are needed like JPA, JAX-RS, JSF, and therefore more libraries have to be packaged with the application, while a EE-compliant application server would have provided it out of the box? 回答1: The question that was in our mind and the entire reason we created TomEE was, why should people have to choose? The whole "Tomcat

问题 I have a standard websocket endpoint based on Tyrus implementation which times to times triggers the java.lang.IllegalStateException: Cannot set WriteListener for non-async or non-upgrade request . We are running on Payara 4.1. My standard implementation @ServerEndpoint(value = "...", decoders=MessageDecoder.class, encoders=MessageEncoder.class) public class EndpointImpl extends AbstractEndpoint{ // onOpen, onClose, onMessage, onError methods } Where the abstract class is public abstract

问题 I'm a bit puzzled regarding the Java timestamp formatting functions as they seem to change the timestamp by a few minutes. My Pivotal CloudFoundry app writes a new entry into a PostgreSQL 9.4.5 database. Doing so, I let PostgreSQL generate and store a timestamp for that entry (within the SQL statement I use 'now()' for that particular column). All that works fine so far. Problems arise when I read the entry with my app because I have to format the timestamp to ISO 8601 (company policy) and

问题 I'm a bit puzzled regarding the Java timestamp formatting functions as they seem to change the timestamp by a few minutes. My Pivotal CloudFoundry app writes a new entry into a PostgreSQL 9.4.5 database. Doing so, I let PostgreSQL generate and store a timestamp for that entry (within the SQL statement I use 'now()' for that particular column). All that works fine so far. Problems arise when I read the entry with my app because I have to format the timestamp to ISO 8601 (company policy) and

问题 I have configured two persistent units with the entity managers set up as show below: <bean id="liveEntityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean" p:dataSource-ref="LiveDataSource"> <property name="persistenceUnitName" value="LivePersistenceUnit" /> </bean> <bean id="archiveEntityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean" p:dataSource-ref="ArchiveDataSource"> <property name="persistenceUnitName"

问题 I want to manage user and roles in a dedicated application. For example a user of this application ("customerX boss") can create a new role "customerX employee". If an employee accesses the Java EE application server (GlassFish 3) he should get the role "customerX employee". It sounds simple, but it is not supported by Java EE, because groups are mapped to roles at start-up time and the roles within the application are static. What is the best way to manage user roles at runtime in a Java EE