jakarta-ee

问题 I'm getting the following error using TomEE and JPA: SEVERE: JAVA AGENT NOT INSTALLED. The JPA Persistence Provider requested installation of a ClassFileTransformer which requires a JavaAgent. See http://openejb.apache.org/3.0/javaagent.html Is having a java agent required for openJPA to function properly? (Specifically is it needed for "openjpa.jdbc.SynchronizeMappings") If so, how do I install it properly in eclipse? 回答1: -javaagent:openejb-javaagent-3.0-beta-2.jar Add that to your VM

问题 I'm not sure if this is a generic JEE6 question or if it is a Wildfly 10/JBoss7 EAP implementation specific question. I'm trying to specify/override the default beanName used in my EJB JNDI mapping to something more meaningful to me. For example: LoginManagerBean: @Stateless public class LoginManagerBean extends BaseManagerBean implements LoginManager { .... } LoginManager: @Local public interface LoginManager{ .... } In this context, WF10 will automatically create a JNDI mapping for this EJB

问题 I'm not sure if this is a generic JEE6 question or if it is a Wildfly 10/JBoss7 EAP implementation specific question. I'm trying to specify/override the default beanName used in my EJB JNDI mapping to something more meaningful to me. For example: LoginManagerBean: @Stateless public class LoginManagerBean extends BaseManagerBean implements LoginManager { .... } LoginManager: @Local public interface LoginManager{ .... } In this context, WF10 will automatically create a JNDI mapping for this EJB

问题 Hi I've already worked with Reflection in Java. But if you are using the java standards (e.g. injecting a private field) you have to write a lot of code to get the job done. What is the shortest way to inject a private field in a Java Object? Are there implementations in widely used and production ready libraries? 回答1: Without using external libraries you need to: get the Field instance set the field instance as accessible set the new value As follow: Field f1 = obj.getClass()

问题 I have a JPA program where EclipseLink is the Persistence provider. When I merge an user entity, change its ID, and try to merge the same user instance again, an error is thrown. I rewrite my code to illustrate my problem in the simplest way. User user = userManager.find(1); userManager.merge(user); System.out.println("User is managed? "+userManager.contains(user); user.setId(2); userManager.merge(user); The above code is not in a transaction context. userManager is a stateless session bean

问题 Please take a look at this below line of code in JSF <h:inputText id="name" value="#{customer.name}" /> Quote from java.sun.com: For an initial request of the page containing this tag, the JavaServer Faces implementation evaluates the #{customer.name} expression during the render response phase of the lifecycle. During this phase, the expression merely accesses the value of name from the customer bean, as is done in immediate evaluation. For a postback request, the JavaServer Faces

问题 Please take a look at this below line of code in JSF <h:inputText id="name" value="#{customer.name}" /> Quote from java.sun.com: For an initial request of the page containing this tag, the JavaServer Faces implementation evaluates the #{customer.name} expression during the render response phase of the lifecycle. During this phase, the expression merely accesses the value of name from the customer bean, as is done in immediate evaluation. For a postback request, the JavaServer Faces

问题 I'm trying to test some POJOs with hibernate annotations and I'm getting the same error on and on. I used the same configuration in another project and it all worked fine. I tested the jdbc connection that is used when the hib objects are tested - and the connction works fine. I have found a few other questions asked about the same error but nothing was helpful. The code in testing class with main method: public static void main(String[] args) { SessionFactory factory = new Configuration()

问题 I am new in JAVA EE. My question is, why do we need jackson databind? Because We can receive the Request Params by @ModelAttribute and requests through http PUT or POST by @RequestBody . I can't find a reason why we need jackson databind to convert json/xml to POJO or vice versa. Thanks. 回答1: Why do we need jackson databind? Because representing structured data is much easier using XML (or JSON) than using simple name-value pairs. Because it is more convenient to send and receive JSON from

问题 I am new in JAVA EE. My question is, why do we need jackson databind? Because We can receive the Request Params by @ModelAttribute and requests through http PUT or POST by @RequestBody . I can't find a reason why we need jackson databind to convert json/xml to POJO or vice versa. Thanks. 回答1: Why do we need jackson databind? Because representing structured data is much easier using XML (or JSON) than using simple name-value pairs. Because it is more convenient to send and receive JSON from