semi-sleep

对于如 List<E> 、 List< String > 、 List ，其中 List<E> 称为 parameterized type ， E 称为 (formal) type parameter ， String 称为 actual type argument ， List 称为 raw type 。 Generic 的逻辑意义 原有 java 的类型...

JAAS authentication is performed in a pluggable fashion. This permits applications to remain independent from underlying authentication technologies. New or updated authentication technologies can be ...

Each EntityManager instance is associated with a persistence context. A persistence context defines the scope under which particular entity instances are created, persisted, and removed.To obtain an...

The starting point for developing a JAX-WS web service is a Java class annotated with the javax.jws.WebService annotation. The @WebService annotation defines the class as a web service endpoint.A se...

A session bean is similar to an interactive session. A session bean is not shared; it can have only one client, in the same way that an interactive session can have only one user. Like an interactive ...

UnicastRemoteObject.exportObject expose a remote object at given ip and portLocateRegistry.getRegistry.bind register a remote object to registry, note that registrty is also a remote object, and the...

JTA is useful not only for different database, but also for different connection to the same database. Transaction manager manage Transaction by begin / suspend / getTransaction / setTransactionTime...

/* UndoableEdit and AbstractUndoableEdit */ AbstractUndoableEdit edit = new AbstractUndoableEdit();   // methods fall into 3 categories   // 1.undoable operations // if the alive field is false,...

The for-each loop for (type_name variable_name : [instance of Iterable<T>] or [array]) {} 跟 .net 的 foreach 不同的是， Iterable 中的 type parameter 或 array 中的 element type 必须是 for 中使用的 type 或者其子类。 以下...

In the module XML file, you specify your application's entry point class. In order to compile, a GWT module must specify an entry point. If a GWT module has no entry point, then it can only be inherit...