The Java EE 7 Tutorial
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1.8 Java EE 7 APIs in the Java Platform, Standard Edition 7
Several APIs that are required by the Java EE 7 platform are included in the Java Platform, Standard Edition 7 (Java SE 7) and are thus available to Java EE applications.
1.8.1 Java Database Connectivity API
The Java Database Connectivity (JDBC) API lets you invoke SQL commands from Java programming language methods. You use the JDBC API in an enterprise bean when you have a session bean access the database. You can also use the JDBC API from a servlet or a JSP page to access the database directly without going through an enterprise bean.
The JDBC API has two parts:
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An application-level interface used by the application components to access a database
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A service provider interface to attach a JDBC driver to the Java EE platform
The Java SE 7 platform requires JDBC 4.1.
1.8.2 Java Naming and Directory Interface API
The Java Naming and Directory Interface (JNDI) API provides naming and directory functionality, enabling applications to access multiple naming and directory services, such as LDAP, DNS, and NIS. The JNDI API provides applications with methods for performing standard directory operations, such as associating attributes with objects and searching for objects using their attributes. Using JNDI, a Java EE application can store and retrieve any type of named Java object, allowing Java EE applications to coexist with many legacy applications and systems.
Java EE naming services provide application clients, enterprise beans, and web components with access to a JNDI naming environment. A naming environment allows a component to be customized without the need to access or change the component's source code. A container implements the component's environment and provides it to the component as a JNDI naming context.
The naming environment provides four logical namespaces: java:comp, java:module, java:app, and java:global for objects available to components, modules, or applications or shared by all deployed applications. A Java EE component can access named system-provided and user-defined objects. The names of some system-provided objects, such as a default JDBC DataSource object, a default JMS connection factory, and a JTA UserTransaction object, are stored in the java:comp namespace. The Java EE platform allows a component to name user-defined objects, such as enterprise beans, environment entries, JDBC DataSource objects, and messaging destinations.
A Java EE component can also locate its environment naming context by using JNDI interfaces. A component can create a javax.naming.InitialContext object and look up the environment naming context in InitialContext under the name java:comp/env. A component's naming environment is stored directly in the environment naming context or in any of its direct or indirect subcontexts.
1.8.3 JavaBeans Activation Framework
The JavaBeans Activation Framework (JAF) is used by the JavaMail API. JAF provides standard services to determine the type of an arbitrary piece of data, encapsulate access to it, discover the operations available on it, and create the appropriate JavaBeans component to perform those operations.
1.8.4 Java API for XML Processing
The Java API for XML Processing (JAXP), part of the Java SE platform, supports the processing of XML documents using Document Object Model (DOM), Simple API for XML (SAX), and Extensible Stylesheet Language Transformations (XSLT). JAXP enables applications to parse and transform XML documents independently of a particular XML-processing implementation.
JAXP also provides namespace support, which lets you work with schemas that might otherwise have naming conflicts. Designed to be flexible, JAXP lets you use any XML-compliant parser or XSL processor from within your application and supports the Worldwide Web Consortium (W3C) schema. You can find information on the W3C schema at http://www.w3.org/XML/Schema.
1.8.5 Java Architecture for XML Binding
The Java Architecture for XML Binding (JAXB) provides a convenient way to bind an XML schema to a representation in Java language programs. JAXB can be used independently or in combination with JAX-WS, in which case it provides a standard data binding for web service messages. All Java EE application client containers, web containers, and EJB containers support the JAXB API.
The Java EE 7 platform requires JAXB 2.2.
1.8.6 Java API for XML Web Services
The Java API for XML Web Services (JAX-WS) specification provides support for web services that use the JAXB API for binding XML data to Java objects. The JAX-WS specification defines client APIs for accessing web services as well as techniques for implementing web service endpoints. The Implementing Enterprise Web Services specification describes the deployment of JAX-WS-based services and clients. The EJB and Java Servlet specifications also describe aspects of such deployment. JAX-WS-based applications can be deployed using any of these deployment models.
The JAX-WS specification describes the support for message handlers that can process message requests and responses. In general, these message handlers execute in the same container and with the same privileges and execution context as the JAX-WS client or endpoint component with which they are associated. These message handlers have access to the same JNDI namespace as their associated component. Custom serializers and deserializers, if supported, are treated in the same way as message handlers.
The Java EE 7 platform requires JAX-WS 2.2.
1.8.7 SOAP with Attachments API for Java
The SOAP with Attachments API for Java (SAAJ) is a low-level API on which JAX-WS depends. SAAJ enables the production and consumption of messages that conform to the SOAP 1.1 and 1.2 specifications and the SOAP with Attachments note. Most developers do not use the SAAJ API, instead using the higher-level JAX-WS API.
1.8.8 Java Authentication and Authorization Service
The Java Authentication and Authorization Service (JAAS) provides a way for a Java EE application to authenticate and authorize a specific user or group of users to run it.
JAAS is a Java programming language version of the standard Pluggable Authentication Module (PAM) framework, which extends the Java platform security architecture to support user-based authorization.
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