¿Qué es la referencia de recursos?

What is resource reference?

A resource reference supports application access to a resource (such as a data source, URL, or mail provider) using a logical name rather than the actual name in the runtime environment.

The ejb-ref-name element serves two purposes in the web. xml deployment descriptor: It is the name that the user code (servlet or JSP) uses to look up the EJB. Therefore, if your ejb-ref-name element is ejb1 , you would perform a JNDI name lookup for ejb1 relative to java:comp/env .

Answer: JDBC is java database API, while JNDI is java native directory API. In short words: JDBC is a Database realm, JNDI lets you store Objects in a virtual context (the Directory) that can be local, remote (Implementation details usually don’t matters).

The Java Naming and Directory Interface (JNDI) is a Java API for a directory service that allows Java software clients to discover and look up data and resources (in the form of Java objects) via a name. connecting a Java application to an external directory service (such as an address database or an LDAP server)

How does one cite a source?

1. For books: author, title, place of publication, publisher, and publication year.
2. For articles: author, title of article, title of journal, volume, issue, date, and page numbers.
3. For web page resources: author, title of page, Web address or URL, and date of access.

Items within the Reference Collection tend to include:

• Dictionaries (both language and topical)
• Encyclopedias.
• Bibliographies (lists of resources on a specific topic)
• Research handbooks and guides.
• Catalogs.
• Atlases and maps.
• Directories.

Add a resource reference:

1. In the Design view, click Add.
2. In the Add Item window, select Resource Reference. Click OK.
3. In the Name field, type the name of your resource reference, for example: SAMPLE.
4. In the Binding Name field, type the name of your resource reference, for example: jdbc/SAMPLE.

introduces another layer of indirection: you specify the name you want to use in the web. xml, and, depending on the container, provide a binding in a container-specific configuration file.

The WebLogic Server JNDI Service Provider Interface (SPI) provides an InitialContext implementation that allows remote Java clients to connect to WebLogic Server. Enter that name in the JNDI Name attribute field when you create the object. When the object is loaded, JNDI provides a path to the object.

The security-role-ref element links a security role name defined by to an alternative role name that is hard-coded in the servlet logic. This extra layer of abstraction allows the servlet to be configured at deployment without changing servlet code.

The resource-ref definition seems a bit redundant to me and I can’t think of when it might be useful. Example: You can always refer to resources in your application directly by their JNDI name as configured in the container, but if you do so, essentially you are wiring the container-specific name into your code.

Web resources represent files that can be used to extend the Common Data Service web application such as html files, JavaScript, and CSS, and several image formats. You can use web resources in form customizations, the SiteMap, or the application ribbon because they can be referenced by using URL syntax.

The optional ejb-ref element defines a reference to an EJB resource. This reference is mapped to the actual location of the EJB at deployment time by defining the mapping in the WebLogic-specific deployment descriptor file, weblogic.xml. Use a separate element to define each reference EJB name.