JPA

The plug-in manifest editor shows the contents of the two plug-in manifest file , meta-info/manifest.mf and plugin.xml, which define how this plugin relates to all the others in the system. View must implement the org.eclipse.ui.IViewPart interface. Typically, views are subclasses of org.eclipse.ui.part.ViewPart and thus indirectly subclass of org.eclipse.ui.part.WorkbenchPart, inheriting much of the behavior needed to implement the IViewPart interface.

p2 is the provisioning system developed by the equinox project. It is a powerful replacement for the original eclipse update manager included with the eclipse platform.Installation and updates are managed in eclipse by the provisioning platform called p2.

A connector ,also known as a provider or a transport, allows a component to send or receive data across a specific protocol. Three principal types of routing pattern are available in mule.

Mule is a lightweight event-driven enterprise service bus and an integration platform.

While there are many different perspectives on what the most important files are in WAS, the key components we will concentrate on can be found in the /plugins directory.    The runtime allows components to have theiw manifest.mf or plugin.xml file read at startup dynamically.

In its purest sense, a jvm simply runs an instruction set for a machine that does not exist in hardware ,but rather in software.It must handle multitasking,allocate and manage memory,load and free applications and classes.

Spring is a container in the sense that it contains and manages the life cycle and configuration of application objects.By default, all spring beans are singletons.When using Hibernate with spring, you will wire a localsessionfactorybean into the container.The LocalSessionFactoryBean has a mappingResources property that takes a list of string containing the names of Hibernate mapping files.

Core builds on Base by offering additional facilities for parsing widgets, advanced animation effects, drag-and-drop facilities,internationalization,back-button handling,managing cookies,and more. Session beans are java components that run in either stand-alone EJB containers or application servers.A stateless session bean class is any standard java class that has a class-level annotation of @Stateless. A stateless session business interface is a standard java interface that does not extend any EJB-specific interfaces.This interafce has a list of business method definitions that will be available for the client application. Business interfaces can use annotaion as well, as described in the following list: The @Remote annotation can be used denote the remote business interface.The @Local annotation can be used to denote the local business interface.If no annotation is specified in the interface, then it is defaulted to the local interface.


A callback method can be any method in the session bean that has callback annotations. The EJB container calls these methods at the appropriate stages of the bean's life cycle.Following are two such callbacks for stateless session beans:

PostConstruct and PreDestroy:PostConstruct callbacks happen after a bean instance is instantiated in the EJB container.The EJB specification provides annotations called interceptors, which allow you to intercept a business method invocation.An interceptor method can be defined for session and message-driven beans.You can either add an @AroundInvoke annotation on a particular method, or you can define an interceptor class whose methods are invoked before a business method is invoked in the bean class.An interceptor class is denoted by the @Interceptor annotation on the bean class with which it is associated.

WSDL details can be split into two categories:service interface definition details and service implementation definition details.The service interface definition contains the following WSDL elements, which comprise the reusable portion of the service description: definiyions, types,message.portType, binding.

The service implementation definition part of the WSDL docuement identifies a web service. It contains the following elements: service and port.

Simple Object Access Protocol is an XML-based protocol used for exchanding information in a decentralized and distributed environment using XML.A SOAP message is an ordinary XML docuement containing the following elements:The required Envelope element identifies the XML document as a SOAP message.Envelope is the top-level element in the docuement. The envelope is required, and basically marks the start and end of the SOAP message.The envelope contains the Header and the Body elements.

JAX-WS provides mapping facilities between WSDL and Java interfaces, or from Java interfaces to WSDL.

Every time you run a java application, you are in fact running your application within an instance of the JVM, and each separate application you run will have its own JVM instance. The JVM specification defines an abstract internal architecture for this proces.


A java stack frame stores the state of method invocations. The stack frame stores data and partial result and inculdes the method's execution environment,any local variables used for the method invocation, and the method's operand stack. The operand stack stores the parameters and return values for most bytecode instructions. The execution environment contains pointers to various aspects of the method invocations.


Java includes some useful predefined annotations, but what makes annnotations potentially even more powerful is that you can easily define your own. Examing the documentation for Target reveals that its single element is an array of ElementType instances, where ElementType is a type-safe enumeration that defines enumeration constants for the supported program elements mentioned earlies that are supported by annotations.

One final point is worth making:since Target defines an array of ElementType values, it is possible for you specify more than one type when using the Target annotation.Like Target, the Retension annotation is used to annotate other annotations,and it's defined within the java.lang.annotation package.It allows you to specify one of three retention policies. each of which corresponds to an instance of RetentionPolicy enumeration type.The three retention polices are as follows;

SOURCE: The annotation information is stored only within the source file, and no remant of it should be stored in a class file generated from that source file.

CLASS:The annotation information is stored within the class file when the source code is compiled, but the information is not loaded into memory as the part of the class definition. This is the default if you create a custom annotation but do not specify a retention policy.

RUNTIME: The annotation data is stored within the class file and loaded into memory when the class definition is loaded.

Deployment diagrams model the runtime requirements of the system,memory requirements for the system, or other devices the system requires during execution.Package diagrams mode the heiarchical structure of packages in the system at compile-time and the relationships that exists between the packages.Composite structure diagrams model the internal structure of a complex object at runtime.

Like most areas of JFace, the preference framework is divided into a series of interfaces, each of which has a default implementation.The preference framework is an extension of the JFace dialog framework. The abstract class PreferencePage forms the basis of all implementations of IPreferencePage provided by JFace.Extending from DialogPage, PreferencePage provides much of the support needed to display preference in a dialog, including a title and an optional image.Preference are not very useful if they must be reset each time an application is launched. JFace provides a way to make your preference persistent using the IPerferenceStore.


An IPreferenceStore maps preference names to values. Each named preference may have a default value and a current value;If there is no current value, the default is returned.JFace includes PreferenceStore , an implementation of IPreferenceStore that is based on the java.util.Properies class.

All activators must implement the BundleActivator interface. Typically, UI-based plug-ins have an activator that subclasses AbstractUIPlugin.When the plug-in shuts down, AbstractUIPlugin automatically saves any plug-in preference that are accessed using the getPreferenceStore() method.When subclassing the Plugin class directly, modify the stop() method to save the preference so that preference will persist across sessions.

A Dojo widget is a collection of DOM elements and javascript objects that work together to provide a single control for manipulating the application.


Core builds on Base by offering additional facilities for parsing widgets, advanced animation effects, drag-and drop facilities, internationalization, back-button handling,managing cookies and more.

The parser is one of the most commonly used resources in all of core. As it turns out, however, it is most frequently used to parse widgets in the page and. The most common use case for the parser is to find and instantiate widgets before addOnLoad fires as the page is loading.The parser finds widgets by finding all of the tags that contain a special dojoType attribute,which designates the resource name for the widget that should be swapped in.

OSGI provides a mechanism for defining and running separate components and a services mechanism to support inter-bundle collaboration.

p2 exposes a set of provisional APIs that can be used to fully customize the install experience for your application.


A NodeList is a specialized subclass of Array that is expressly designed with some fantastic extensions for manipulation collections of DOM nodes with ease.


The dojo.declare function provides a basic pattern for handling classes that is important to understand because Dijit expands upon it to deliver a flexible creation pattern that effectively automates the various tasks entailed in creating a widget.


The java Persistence API is  a lightweight, POJO-based framework for java persistence.The fields in the entity are automatically made persistable by virtue of their existence in the entity.Default mapping and loading configuration values apply to these fields and enable them to be persisted when the object is persisted.

Resuable chunks of code are called resources and collections of related resources are grouped into what are known as modules.In short, you include a dojo.provide statement as the first line of a file that you want to make available for a dojo.require statement to pull into a page.

Node manager is ready-to-run after weblogic server installation if you run node manager and the administration server on the same machine. You can start a manager server using node manager through the administration console. A weblogic server instance is the process responsible for receiving incoming requests from the user,provides the java ee containers necessary to deploy any applications. The sever instances that constitute a cluster can run on the same machine, or be located on different machines.You can increase a cluster's capacity by adding additional server instances to the cluster on an existing machine, or you can add machines to the cluster to host the incremental server instances.Each server instance in a cluster must run the same version of weblogic server.

Weblogic sever provides the following tools to help you configure and deploy applications:


The administratio console provides a series of web-based deployment assistants that guide you through the deployment process. The administration console also provides controls for changing and monitoring the deployment status, and changing selected deployment descriptor values while the deployment unit is up and running.Managed servers can use the following resources:machine definitions that identify a particular,physical piece of hardware. A machine definition is used to associate a computer with the managed servers it hosts. This information is used by the node manager in restarting a failed managed server, and by a clustered managed server in selecting the best location for storing replicated session data.

The domain log file provides a central location from which to view the overall status of the domain.The domain log resides in the administration server logs directory.Server instances in a weblogic server production environment are often distributed across multiple domains,machines, and geographic locations. Node manager is a weblogic server utility that enables you to start, shut down, and restart administration server and managed server instances from a remote location.A node manager process is not associated with a specific weblogix domain ,but with a machine.You can use the same Node manager process to control  server instances in any weblogic server domain,as long as the server instances reside on the same machines as the node manager process.


Like the joined strategy, the InheritanceType.TABLE_PER_CLASS strategy uses a different table for each class in the hierarchy.Unlike the joined strategy, however,each table includes all state for an instance of the corresponding class. Thus to load a subclass instance, the JPA  implementation must only read from the subclass table;It does not need to join to superclass tables.

We have already seen mappings such as the many-to-many and unidirectional one-to-many mappings that use join tables.