weblogic Introduction

WebLogic Server

“WebLogic is a server software application that runs on middle tier, between backend databases, related applications and browser based thin clients. “
Paul Ambrose, Bob Pasker, Laurie Pitman, and Carl Resnikoff founded WebLogic, Inc. in September 1995. The founders worked together to pursue what eventually became the "Application Server".
BEA Systems acquired WebLogic, Inc. in 1998.
Oracle Corporation acquired BEA Systems in 2008.
Following the success of the Java platform, the term application server sometimes refers to a J2EE or Java EE 5 application server. Some of the better-known Java Enterprise Edition application servers include:
 WebSphere Application Server and WebSphere Application Server Community Edition (IBM)
 Sybase Enterprise Application Server (Sybase Inc)
 Oracle WebLogic Server (Oracle)
 ATG Dynamo (ATG)
 JBoss (Red Hat)
 JRun (Adobe Systems)
 Apache Geronimo (Apache Software Foundation)
 Oracle OC4J (Oracle)
 Sun GlassFish Enterprise Server (based on GlassFish Application Server) (Sun Microsystems)
 SAP Netweaver AS (ABAP/Java) (SAP)
 Glassfish Application Server (open source)
 WebObjects (Apple Inc.)
 Pramati Application Server (Pramati Technologies)

Application Architecture:

WebLogic Features:

WebLogic Server provides essential features for developing and deploying mission-critical e-commerce applications across distributed, heterogeneous computing environments. These features include the following:

 Standards leadership—Comprehensive enterprise Java supports to ease the implementation and deployment of application components. WebLogic Server is the first independently developed Java application server to achieve J2EE certification. In addition, BEA actively participates in the development of J2EE and Web Services standards that drive innovation and advancement in Java and XML technology.

 Rich client options—WebLogic Server supports Web browsers and other clients that use HTTP; Java clients that use RMI (Remote Method Invocation) or IIOP (Internet Inter-ORB Protocol); SOAP clients on any SOAP-enabled plaftorm; and mobile devices that use (WAP) Wireless Access Protocol. Connectors from BEA and other companies enable virtually any client or legacy application to work with a WebLogic Server application.

 Flexible Web services—WebLogic Server provides a solid platform for deploying Web services as components of a heterogeneous distributed application. Web services use a cross-platform, cross-language data model (XML) to provide interoperability among application components on diverse hardware and software platforms. Web services support user-defined data types and one-way asynchronous operations. A Web service can intercept SOAP messages for further processing. New Ant tasks automatically generate important components and package the service into a deployable EAR file.

WebLogic Server uses Web Services Description Language (WSDL) 1.1, an XML-based specification, to describe Web services. WebLogic Web services support Simple Object Access Protocol (SOAP) 1.1 and 1.2 as the message format and HTTP as a connection protocol.
Note: WebLogic Web services accept both SOAP 1.1 and 1.2 incoming requests, but produce only SOAP 1.1 outgoing responses.

 Enterprise e-business scalability—Efficient use and high availability of critical resources are achieved through Enterprise JavaBean business components and mechanisms such as WebLogic Server clustering for dynamic Web pages, backend resource pooling, and connection sharing.

 Robust administration—WebLogic Server offers a Web-based Administration Console for configuring and monitoring WebLogic Server services. A command-line interface for configuration makes it convenient to administer WebLogic Servers with scripts.

 E-commerce-ready security—WebLogic Server provides Secure Sockets Layer (SSL) support for encrypting data transmitted across WebLogic Server, clients, and other servers. User authentication and authorization for all WebLogic Server services are provided through roles and security providers. External security stores, such as Lightweight Directory Access Protocol (LDAP) servers, can still be adapted to WebLogic realms, enabling single sign-on for the enterprise. The Security Service Provider Interface makes it possible to extend WebLogic Security services and to implement WebLogic Security features in applications.

 Maximum development and deployment flexibility—WebLogic Server provides tight integration with and support for leading databases, development tools, and other environments.

 Bi-directional functional interoperability between Java/J2EE objects and Microsoft ActiveX components—BEA WebLogic jCOM provides a run-time component that implements both Component Object Model (COM)/Distributed Component Object Model (DCOM) and Remote Method Invocation (RMI) distributed components infrastructures. This makes the objects look like native objects for each environment.

 Java Message Service (JMS)—An enterprise messaging system, also referred to as message-oriented middleware (MOM), enables applications to communicate with one another through the exchange of messages. A message is a request, report, and/or event that contains information needed to coordinate communication between different applications. A message provides a level of abstraction, allowing you to separate the details about the destination system from the application code.
The Java Message Service (JMS) is a standard API for accessing enterprise messaging systems. Specifically, JMS enables Java applications sharing a messaging system to exchange messages, and it simplifies application development by providing a standard interface for creating, sending, and receiving messages.

WebLogic Versions
 WebLogic Server 11g (10.3.1) JDK 160_11
 WebLogic Server 10.3 JDK 160_05
 WebLogic Server 10.0 JDK 150_11
 WebLogic Server 9.2 JDK 150_12
 WebLogic Server 9.1 JDK 150_13
 WebLogic Server 9.0 JDK
 WebLogic Server 8.1 JDK !42_11
 WebLogic Server 7.0 JDK 131_06
 WebLogic Server 6.1 JDK 131_01
 WebLogic Server 6.0 JDK
 WebLogic Server 5.1 JDK 1.3.1_09

Hardware Requirements:
A Windows computer must have the following minimum configuration.
• A Pentium-class processor running at 400 MHz or faster
• Random Access Memory (RAM)
• 1GB recommended
• 512MB minimum
• 5G available hard drive space
• SVGA monitor
• CD-ROM drive (for installation)
• TCP/IP network interface
• Local area network (LAN) card and persistent Internet connection is required.

Protocol Support:
Client applications connect with WebLogic Server using standard networking protocols over TCP/IP. WebLogic Server listens for connection requests at a network address that can be specified as part of a Uniform Resource Identifier (URI).

Scheme Protocol
HTTP HyperText Transfer Protocol. Used by Web browsers and HTTP-capable programs.
HTTPS Hypertext Transfer Protocol over Secure Sockets Layer (SSL). Used by Web browsers and HTTPS-capable client programs.
T3 WebLogic T3 protocol for Java-to-Java connections, which multiplexes JNDI, RMI, EJB, JDBC, and other WebLogic services over a network connection.
T3S WebLogic T3 protocol over Secure Sockets Layer (SSL).
RMI Remote Method Invocation (RMI), the standard Java facility for distributed applications.
IIOP Internet Inter-ORB protocol, used by CORBA-enabled Java clients to execute WebLogic RMI objects over IIOP. Other CORBA clients connect to WebLogic Server with a CORBA naming context instead of a URI for WebLogic Server.
IIOPS Internet Inter-ORB protocol over Secure Sockets Layer (SSL).
SOAP WebLogic Web services use Simple Object Access Protocol (SOAP) 1.1 as the message format and HTTP as a connection protocol.

Installation Methods
The BEA installation program supports the following methods for installing the BEA WebLogic Platform software:

 Graphical mode
Graphical-mode installation is an interactive, GUI-based method for installing WebLogic Platform. It can be run on both Windows and UNIX systems. For installation procedures, see Installing WebLogic Platform Using Graphical-Mode Installation.
Note: If you want to run graphical-mode installation, the console attached to the machine on which you are installing the software must support a Java-based GUI. All consoles for Windows systems support Java-based GUIs, but not all consoles for UNIX systems do. If you attempt to start the installation program in graphical mode on a system that cannot support a graphical display, the installation program automatically starts console-mode installation.

 Console mode
Console-mode installation is an interactive, text-based method for installing WebLogic Platform, from the command line, on either a UNIX system or a Windows system. For instructions for using this method, see Installing WebLogic Platform Using Console-Mode Installation.

 Silent mode
Silent-mode installation is a noninteractive method of installing WebLogic Platform that requires the use of an XML properties file for selecting installation options. You can run silent-mode installation in either of two ways: as part of a script or from the command line. Silent-mode installation is a way of setting installation configurations only once and then using those configurations to duplicate the installation on many machines. For instructions, see Installing WebLogic Platform Using Silent-Mode Installation.
C:\ server923_win32.cmd –mode=silent –silent_xml=path_to_silent.xml –log=C:\temp\install.log

Difference between Application Server and Web Server

• Web Server serves pages for viewing in web browser, static HTML pages or gifs, jpegs, etc., and can also run code written in CGI, JSP etc. A Web server handles the HTTP and HTTPS protocol.
Ex: IBM web server, Apache web server, IIS web server, Sun one web server, etc.
• An Application Server is used to run business logic or dynamically generated presentation code. It can either .NET based or J2EE based.
Ex: BEA WebLogic Server, IBM WebSphere, JBoss, etc.
• The basic difference between a web server and an application server is
Webserver can execute only web applications i.e. servlets and JSPs and has only a single container known as Web container which is used to interpret/execute web applications.
• Application server can execute Enterprise application, i.e. (servlets, jsps, and EJBs) it is having two containers 1. Web Container(for interpreting/executing servlets and jsps) 2. EJB container (for executing Ejbs). It can perform operations like load balancing, transaction demarcation etc
• Webserver delegation model is fairly simple, when the request comes into the webserver; it simply passes the request to the program best able to handle it (Server side program). It may not support transactions and database connection pooling.
• Application server is more capable of dynamic behaviour than webserver. We can also configure application server to work as a webserver.Simply application server is a superset of webserver.

Administration Tools
• Configuration Wizard
GUI/scriptable tool to create and extend WebLogic domains Template based.
• Administration Console
Browser-based tool for configuring and monitoring domains, deploying applications, and controlling servers.
• WebLogic Scripting Tool (WLST)
Script or command line tool to do the same thing as the Administration Console and Configuration Wizard.
Note: that we will cover details on WLST in a separate document.
• weblogic.Admin
Deprecated command line tool for configuring a domain.
Recommend using WLST instead.
• weblogic.Deployer
Command line tool for deploying applications.

WebLogic Domains:
A domain is the basic administration unit for WebLogic Server instances. It consists of one or more WebLogic Server instances and their associated resources.
• Multiple domains can be created based on different system administrator’s responsibilities, application boundaries, or geographical locations of servers.
• A single domain can be used to centralize all WebLogic Server administration activities.
Each domain’s configuration is stored in a separate configuration file called config.xml, which is stored on the Administration Server along with other files such as logs. When the Administration Server is used to perform a configuration task, the changes apply only to the domain managed by that Administration Server.
The management of a domain is specific to the Administration Server for that domain. Accordingly, this means that server instances, applications, and resources in one domain should be treated as being independent of servers, applications, and resources in a different domain.

Contents of a Domain:
A domain can include multiple WebLogic Server clusters and non-clustered WebLogic Server instances. The scope and purpose of a domain can vary significantly. A minimal domain can contain only one WebLogic Server instance, which functions both as an Administration Server, and as a Managed server. Production Environment: 4 standalone Managed Servers, and a cluster of 4 Managed Servers. WLS Domain may contain Resources like Machine, Node Manager, etc. And services like JMS, JDBC,etc.

Administration Server
The Administration Server operates as the central control entity for the configuration of the entire domain. It maintains the domain's configuration documents and distributes changes in the configuration documents to Managed Servers. You can also use the Administration Server as a central location from which to monitor all resources in a domain.

Managed Server
Managed Servers host business applications, application components, Web services, and their associated resources. To optimize performance, Managed Servers maintain a read-only copy of the domain's configuration document. When a Managed Server starts up, it connects to the domain's Administration Server to synchronize its configuration document with the document that the Administration Server maintains.