I think A is right. When the method Bob is being called, it creates new transaction for it and method Aby gets suspended until the Bob transaction is committed. Also note that it has to be method from some other bean to make it transactional, methods called from the same bean do not act as … Read more
This happens because you have inserted something which is meant to be a foreign key but do not reference anything. Check out you database whether that key exist or not(even though it is in database in other tables).
You can do something like @NamedQuery(name=”findWhatever”, query=”SELECT new path.to.dto.MyDto(e.id, e.otherProperty) FROM Student e WHERE e.id = ?1″) Then the MyDto object would just need a constructor defined with the correct fields i.e. public MyDto(String id, String otherProperty) { this.id = id; this.otherProperty = otherProperty; }
You already know about method calls. What if the object that you want to invoke the method on is on a different computer? You use RMI to send the call from one computer (client) to the other (server). The client will wait (or “block”) until the result comes back from the server. This is called … Read more
The question that was in our mind and the entire reason we created TomEE was, why should people have to choose? The whole “Tomcat or JavaEE” thing is tired and old. After 10 years it still comes up and people argue against each other as to which is better and why. Here’s the math in … Read more
1) Download the JDBC Driver here. 2) unzip the file and go to sqljdbc_version\fra\auth\x86 or \x64 3) copy the sqljdbc_auth.dll to C:\Program Files\Java\jre_Version\bin 4) Finally restart eclipse
Both answers from Eric Lucio and Renan helped, but their use of the ids in the association table is redundant. You have both the associated entities and their ids in the class. This is not required. You can simply map the associated entity in the association class with the @Id on the associated entity field. … Read more
A rolling restart or ripplestart of applications is typically an operation that may be performed on applications that are deployed across multiple JVMs or application servers (for example, in a cluster) to incrementally stop and start applications on each JVM. The purpose may be for an application to pick up configuration changes that require a … Read more
There are a number of Java libraries for data synchronizing/replication. Two that I’m aware of are daffodil and SymmetricDS. In a previous life I foolishly implemented (in Java) my own data replication process. It seems like the sort of thing that should be fairly straightforward, but if the data can be updated in multiple places … Read more
You can use @XmlRootElement if you want to use JAXB annotations (see other answers). However, if you prefer pure POJO mapping, you must do the following (Unfortunately it isn’t written in docs): Add jackson*.jar to your classpath (As stated by @Vitali Bichov); In web.xml, if you’re using com.sun.jersey.config.property.packages init parameter, add org.codehaus.jackson.jaxrs to the list. … Read more