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IBM Italia SpA
© 2007 IBM Corporation| Milan, 26 November 2008 |
WebSphere Application Server - Overview
Marco DragoniIBM Software Group – Technical Sales SpecialistIBM Italia S.p.A.
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Agenda
Course and speaker introductionWhat is an Application ServerModel-View-Controller PatternWebSphere Basic Architecture and mapping to MVC
– EAR file composition– J2EE standard– WebSphere Application Server Family
Understand difference between Basic and Network Deployment
Accessing Application Server ResourceA typical application flow
HTTP Server and Plug-in Class Loader roleJNDI roleJDBC resource
Web Services for J2EE
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Who am I and what is my job ?
Marco Dragoni
Working for IBM from 1990 at present as WebSphere Technical Sales inside SWG (Software Group)
– My job consist of provide technical assistance during the sell cycle to the seller people through technical presentation, PoC, lab exercise and support for critical situation. This for some products of WebSphere family (focus on BPM).
SoftwareCertification :
2007 IT Specialist2007 IBM Certified SOA Associate (664)2007 IBM Certified SOA Solution Designer (667)2007 WebSphere Integration Developer (094)2008 WebSphere ND 6.1 Advanced System Administrator (806)
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Course Introduction
26 November 2008 (08.30-10.30) – WebSphere Application Server Overview (Marco Dragoni)
28 November 2008 (13.30-15.30) – BPM and SOA and IBM products description (Marco Dragoni)
02 December 2008 (11.30-14.30) LAB 01 – Building a simple service-oriented application through step-by-step instruction
09 December 2008 (11.30-14.30) LAB 02 – Build a process to integrate an existing web application to obtain a complete sell cycle
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What is an Application Server
An Application Server is a runtime environment for hosting applications that are written following the J2EE specificationAn Applications Server, compliant with J2EE specification, offers services such as Security (JASS), Transaction (JTA), Messaging (JMS), Naming Services (JNDI), Database Connectivity (JDBC), etc.Any Web applications that are written to the J2EE specification can be installed and deployed on the serverJ2EE is:
– An open and standard based platform for developing, deploying and managing n-tier, Web-enabled, server-centric, and component-based enterprise applications
J2EE add value to
– Developer
– Vendors
– Business Customer
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A Brief History of Enterprise Java
2000
EJB 1.0Servlet 2.1
1998J2EE 1.2•EJB•Servlet•JSP•JMS•JavaMail
J2EE 1.3•EJB
local EJBsabs. CMPMDB
•Servlet 2.3EventsFilters
•JSPXML
•JAXP•Connectors•JAAS
2001 J2EE 1.4•EJB 2.1
timerspluggable JMS
•Web ServicesBasic SOAP/HTTPRegistry
•JMX Mgmt•J2EE Deployment•JACC
2003
2006
Java EE 5•EJB 3
POJO componentsPOJO persistence
•Web ServicesPOJO componentsprotocol independenceJAXBStAX
•JSF•JSP
common EL•Annotations
IoC
BPEL
PortletsSDO
SCAHibernate
Spring
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J2EE – MVC Pattern (Model - View - Controller)
Model to represent the underlying data and business logic behaviuor in one place (Entity and Session EJB). Make data and behaviour independent from presentation. Represented by EJB.View display information according to client types, display result of business logic. Represented by JSP.Controller serves as the logical connection between the users interaction and the business services on the back. Represented by Servlet.
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J2EE Architecture
Web Tier EJB Tier
The Presentation Tier processes input from the Client Side Tier, calls components in the Business Logic Tier, and then sends a response back to the Client Side Tier (Servlet, JSP)The Business Logic Tier provides a framework for executing business logic and for accessing business data in a distributed transactional environment (EJB)
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Web Applications and anatomies
It is often advantageous to treat each layer as an independent portion of your applicationDo not confuse logical separation of responsibilities with actual separation of componentsSome of the layers can be combined into single components to reduce application complexity
J2EE application anatomies samples:– HTML client, JSP/Servlets, EJB, JDBC/Connector (4 tiers)– HTML client, JSP/Servlets, JDBC (3 tiers)– EJB standalone applications, EJB, JDBC/Connector (3 tiers)
When to use EJB ?– Application needs to be scalable or support variety of clients, transactions are
required to ensure data integrity, make data and behaviour independent from presentation, manage business logic behaviuor in one place .
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Java EE Application Components
Web Module
HTML
Java beans
Servlet/JSP
DeploymentDescriptor
EJB Module
DeploymentDescriptor
Session
Entity
MDB
ResourceAdapter (RAR)
DeploymentDescriptor
RA JavaClasses
ApplicationClient Module
DeploymentDescriptor
RA JavaClasses
Main Class
DeploymentDescriptor
Runs in Application ServerRuns in ApplicationClient Container
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WebSphere AS Packaging
WebSphere Process Server
Process ChoreographyBusiness Rules EngineWebSphere
ESBMediation Functions
WebSphere XDDynamic OperationHigh Performance ComputingManagement Facility
ClusteringFailoverWorkload Mgmt
Distributed Administration Web Services
UDDI RegistryWeb Services Gat.
Edge ComponentsIBM Ldap for prod env.TAM for prod env.DB2 Session Persistance
WebSphere ND
Application ServerExpress/Base
Extended Transaction SupportApplication ProfilingAsynchronous ExecutionDynamic QuerySchedulingStartup Beans
Service Integration Bus
WebSphere CE
Based on Apache Geronimo
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WebSphere AS Basic Architecture
MessagingEngine
Em
bedded HT
TP
Server
Web Container
Servlet JSPs
EJB Container
EJBs
ApplicationDatabasesApplicationData
XML Configuration
Files
HTTP Server Plug-in
HTTP Server
Application ServerApplication Server
Plug-in Configuration File
Dynamic Cache Name Server Security
… … ….
Web ServicesEngine
Data Replication JMX Transaction.
HTTP/S
Web Browser
HTTP/S
Balancing and static content
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WebSphere AS Basic Administration
Application Server
WEB Container
Embedded HTTP Server9060
Administrative Services
Administrative Console
Application
Soap/HTTPor
RMI-IIOP
WebSphereWebSphereAdministrative ClientsAdministrative Clients
Custom Java Administrative
Clients
Scripting Client (wsadmin)
Web Browser
Update
Configuration Repository
Internet or Intranet
ConfigFiles
J2EEApps
(EARs)
Stand-alone Node
Administrative Console run inside the same JVM running customer application
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WebSphere AS Express, Base – Sample Topologies
Http Server + WebSphere Plug-in WebSphere AS Database/EIS
HTTP Server
WAS
Database/EIS
All in one machine
Easy to maintain
Low cost
Low performance
All in different machine
A DMZ can be established
No competition between DB and other resources (different tuning)
DMZ Network Intranet Network
Example 1
Example 2
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WebSphere AS Network Deployment Architecture
A deployment manager process manages the node agents
– Holds the configuration repository for the entire management domain, called a cell
– Administrative Console runs inside the DMgr
A node is a logical grouping of servers
– Each node is managed by a single node agent process
– A managed node is a node that contains a node agent
– An unmanaged node is a node in the cell without a node agent
Enables the rest of the environment to be aware of the node
V6 Node
V6 Application
Server
V6 Application
Server…
V6 Node
V6 Application
Server
V6 Application
Server…
…
Cell
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Network Deployment : File synchronization
Deployment manager contains the master configuration
Node agents synchronize their files with the master copy
AutomaticallyAt start upPeriodically
ManuallyAdministrative consoleCommand line
During synchronization1. Node agent asks for changes to
master configuration2. New or updated files are copied to
the node
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V6 Node
V6 Application
Server
V6 Application
Server…V6 Node
V6 Application
Server
V6 Application
Server……
ConfigFiles
J2EEApps
(EARs)
ConfigFiles
J2EEApps
(EARs)
ConfigFiles
J2EEApps
(EARs)
Network Deployment : System Administration
Administrative ClientsAdministrative Clients
ND allows you to manage the entire cell (all processes) from a central Deployment Manager
– Administrative clients connect to Deployment ManagerChanges made by the administrative clients are saved in the master configurationThe configuration is then synchronized with the Nodes
Master Configuration forthe Entire Cell
V6 Deployment Manager
WEB Container
Embedded HTTP Server
Administrative Services
Administrative Console
Application
9060Internet
or Intranet
Soap/HTTPor
RMI-IIOP
Custom Java Administrative
Clients
Scripting Client (wsadmin)
Web Browser
ConfigFiles
J2EEApps
(EARs)
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WebSphere AS Example configuration (ND package)
WebSphere AS Cluster1 (3 JVM)
WebSphere AS Cluster2 (2 JVM)
WebSphere AS Infrastructure (3 JVM – 2NA + 1 DMGR) and WebSphere Plug-in on HTTP Server
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How to access Application Server Resources
Web browserHTTP(S)
Messaging Engine
Em
bedded HT
TP
Server
WebContainer
EJBContainer
Application ServerApplication Server
Web Services Engine
Servlets/JSPs EJBs
Java client
Web Servicesclient
RMI/IIOP SOAP/JMS
SOAP/HTTP(S)
JMS Client
REST/AJAX
Asynchronous Communication
.Net and Java communication
Java to Java communication
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Consideration on accessing resources
Use HTTP when you need a standard user interface, like your browser, to access the resources available inside the Application Server. UI content enrichment can be done through Web 2.0 technology (AJAX, REST, JSON). AS resources access from Internet (HTTP is a standard protocol).
Use web services when interaction is machine-to-machine (a web services client is a program executed in another machine, usually a remote machine) and you need to interact between heterogeneous environment (Java and .Net). AS resources access is from Internet (HTTP is a standard protocol).
Use RMI/IIOP directly when instead of a browser you are building a standalone Java application for your desktop (the user interface is a java application, so you do not need the presentation layer) or you need a faster communication between Java application.
Use JMS when you need an asynchronous communication between components (mainly used from other program)
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A new emerging way to access resources
JSON and HTTP EnablementSimplifies Ajax and web 2.0 based access to traditional web services, Java objects and EJBs in the application server
Ajax Client RuntimeEases development of client side Ajax code; based on Dojo, an open source JavaScript library
Publish and Subscribe Event HandlingEnables dynamic scenarios such as streaming stock updates and real time collaborative web applications
Ajax ProxyProvides safe, reliable access to Internet based services and mashups from browser based Ajax applications
IBM $125.25 +$2.50… MSFT $43.75 -$1.50 …
EJBs POJOsServices
JMS Proxy
WebSphereApplication Server
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Web 2.0 style services – key concepts
REST– REpresentational State Transfer– Server side architectural style relying on HTTP
semantics to access services or resources– Easily invoked by browsers via Ajax
JSON– JavaScript Object Notation– Data format used to exchange information between
browser and a service– Directly consumable by JavaScript clients
Ajax– Asynchronous JavaScript And XML– Browser based technology to provide highly interactive
and responsive web pages– Enables the browser to invoke services directly from the
client
Browser
service
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The flow of an application
Phase 1 1,2,3,4,5
Phase 26
Phase 3 7,8a,8b,9
Phase 4 10
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Plug-in configuration file
The plug-in configuration file (plugin-cfg.xml) contains routing information for all applications mapped to the Web server. This file is read by a binary plug-in module loaded in the Web server.
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Plug-in XML tag description
VirtualHostGroup, VirtualHost: – A group of virtual host names and ports that will be specified in the HTTP Host header when the user
tries to retrieve a page. Enables you to group virtual host definitions together that are configured to handle similar types of requests. The requested host and port number are matched to a VirtualHosttag in a VirtualHostGroup.
UriGroup, Uri :– A group of URIs that will be specified on the HTTP request line. The incoming client URI is compared
with all the Uri tags in the UriGroup to see if there is a match to determine if the application server will handle the request for the Route in conjunction with a virtual host match.
Route:– The Route definition is the central element of the plug-in configuration. It specifies how the plug-in
will handle requests based on certain characteristics of the request. The Route definition contains the other main elements: a required ServerCluster, and either a VirtualHostGroup, UriGroup, or both. Using the information that is defined in the VirtualHostGroup and the UriGroup for the Route, the plug-in determines if the incoming request to the Web server should be sent on to the ServerClusterdefined in this Route. The plug-in sets scores for Routes if there is a VirtualHost and Uri match for an incoming request. Once the plug-in processes all Routes, the Route chosen is the one with the highest score.
ServerCluster, Server:– The located ServerCluster from the Route tag contains a list of Server tags that in turn contain the
requested object. The ServerCluster located by finding the correct Route can optionally specify theWLM algorithm. This will then be used to select one Server from within the ServerGroup.
Transport:– Once a Server has been located, its Transport tags describe how to connect to it.
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Plug-in workload management policies
Weighted round robin– When using this algorithm, the plug-in selects a cluster member at random from which
to start. The first successful browser request is routed to this cluster member and then its weight is decremented by 1. New browser requests are then sent round robin to the other application servers and subsequently the weight for each application server is decremented by 1. The spreading of the load is equal between application servers until one application server reaches a weight of 0. From then on, only application servers with a weight higher than 0 will have requests routed to them. The only exception to this pattern is when a cluster member is added or restarted or when session affinity (next slide) comes into play.
Random– Requests are passed to cluster members randomly. Weights are not taken into
account as with round robin. The only time the application servers are not chosen randomly is when there are requests with sessions associated with them. When the random setting is used, cluster member selection does not take into account where the last request was handled. This means that a new request could be handled by the same cluster member as the last request.
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Plug-in configuration file – Session Affinity
In a clustered environment, any HTTP requests associated with an HTTP session must be routed to the same Web application in the same JVM.
This ensures that all of the HTTP requests are processed with a consistent view of the user’s HTTP session.
The exception to this rule is when the cluster member fails or has to be shut down.
content valueCache ID 0000Session ID SHOQmBQ8EokAQtzl_HYdxItseparator :Clone ID vuel491u
<?xml version="1.0" encoding="ISO-8859-1"?><!--HTTP server plugin config file
for the cell ITSOCell generated on 2004.10.15 at 07:21:03 PM BST--><Config>......<ServerCluster Name="MyCluster"><Server CloneID="vuel491u" LoadBalanceWeight="2"
Name="NodeA_server1"><Transport Hostname="wan" Port="9080" Protocol="http"/><Transport Hostname="wan" Port="9443" Protocol="https">......</Config>
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Plug-in configuration file – Session Failover
Server clusters provide a solution for failure of an application server. Sessions created by cluster members in the server cluster share a common persistent session store (Memory or Database). Any cluster member in the server cluster has the ability to see any user’s session saved to persistent storage If one of the cluster members fail, the user can continue to use session information from another cluster member in the server cluster. This is known as failover. Failover works regardless of whether the nodes reside on the same machine or several machines.
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Java Class Loader
Class loaders enable the Java virtual machine (JVM) to load classes. Given the name of a class, the class loader locates the definition of this class. Each Java class must be loaded by a class loader.
When you start a JVM, you use three class loaders: the Bootstrap class loader (<JAVA_HOME>/lib), the Extensions class loader (<JAVA_HOME>/lib/ext), and the System class loader (CLASSPATH).
The Extensions class loader is the parent for the System class loader. The Bootstrap class loader is the parent for the Extensions class loader. The class loaders hierarchy is shown
Delegation is a key concept to understand when dealing with class loaders
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ClassLoader behavior example
A class called WhichClassLoader1 loads a class called WhichClassLoader2, in turn invoking a class called WhichClassLoader3
If all WhichClassLoaderX classes are put on the system class path, the three classes are loaded by the System class loader, and this sample runs just fine.
Now suppose you package the WhichClassLoader2.class file in a JAR file that you store under <JAVA_HOME>/lib/ext directory.
As you can image, the program fails with a NoClassDefFoundError exception, which might sound strange because WhichClassLoader3 is on the system class path. The problem is that it is on the wrong class path.
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ClassLoader behavior example cont.
The WhichClassLoader2 class was loaded by the Extensions class loader. In fact, the System class loader delegated the load of the WhichClassLoader2 class to the Extensions class loader, which delegated the load to the Bootstrap class loader. Because the Bootstrap class loader could not find the class, the class loading control was returned to the Extensions class loader. The Extensions class loader found the class and loaded it.
Now, the Extensions class loader needs to load the WhichClassLoader3 class. It delegates to the Bootstrap class path, which cannot find the class, then tries to load it itself and does not find it either.
A NoClassDefFoundError exception is thrown. Once a class is loaded by a class loader, any new classes that it tries to load reuse the same class loader, or go up the hierarchy to find a class.
A class loader can only find classes by going up the hierarchy, never down.
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WebSphere Class Loader policies
The top box in red represents the Java (Bootstrap, Extension and System) class loaders. WebSphere loads just enough here to get itself bootstrapped and initialize the WebSphere extension class loader.
The WebSphere extensions class loader is where WebSphere itself is loaded
EJB modules, utility JARs, resource adapters files, and shared libraries associated with an application are always grouped together into the same class loader. This class loader is called the Application class loader.
Depending on the application class loader policy, this application class loader can be shared by multiple applications (EARs), or be unique for each application, which is the default.
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WebSphere ClassLoader policies cont.There are settings in WAS that allow you to influence WebSphere class loader behavior.
– When the application class loader policy is set to Single, a single application class loader is used to load all EJBs, utility JARs, and shared libraries within the application server (JVM). If the WAR class loader policy then has been set to Application, the Web module contents for this particular application are also loaded by this single class loader.
– When the application class loading policy is set to Multiple, the default, each application will receive its own class loader for loading EJBs, utility JARs, and shared libraries. Depending on whether the WAR class loader loading policy is set to Module or Application, the Web module might or might not receive its own class loader.
Module
Multiple Single
Application
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WebSphere ClassLoader delegation
WebSphere’s application class loader and WAR class loader both have a setting called the class loader mode.
There are two possible values for the class loader mode: PARENT_FIRST and PARENT_LAST
PARENT_FIRST. This mode causes the class loader to first delegate the loading of classes to its parent class loader before attempting to load the class from its local class path. This is the default policy for standard Java class loaders.
PARENT_LAST, the class loader attempts to load classes from its local class path before delegating the class loading to its parent. This policy allows an application class loader to override and provide its own version of a class that exists in the parent class loader.
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JNDI
WebSphere Application Server provides a JNDI implementation that you can use to access CosNaming name servers through the JNDI interfaceCosNaming provides the server-side implementation and is where the name space is stored. JNDI essentially provides a client-side wrapper of the name space stored in CosNaming, and interacts with the CosNaming server on behalf of the client.WebSphere application clients use the naming service to obtain references to objects related to those applications, such as EJB homes. These objects are bound into a mostly hierarchical structure, referred to as a name space. In this structure, all non-leaf objects are called contexts.
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JNDI
Naming operations, such as lookups and binds, are performed on contexts.
All naming operations begin with obtaining an initial context. You can view the initial context as a starting point in the name space. For example:
– The name myApp/myEJB consists of one non-leaf binding with the name myApp, which is a context.
– The name also includes one leaf binding with the name myEJB, relative to myApp. The object bound with the name myEJB in this example happens to be an EJB home reference.
– The whole name myApp/myEJB is relative to the initial context, which can be viewed as a starting place when performing naming operations.
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JNDI
The name space can be accessed and manipulated through a name server.
Users of a name server are referred to as naming clients
Naming clients typically use Java Naming and Directory Interface (JNDI) to perform naming operations. Naming clients can also use the Common Object Request Broker Architecture (CORBA) CosNaming interface.
Notice that all WebSphere Application Server processes host their own naming service and local name space (remove bottleneck)
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JNDI
There are three options available for binding EJB (<ejb-ref>) and resource (<resource-ref>) object names to the WebSphere Application Server name space:
– Simple name -- ejb/webbank/Account
– Compound/fully qualified name -- cell/nodes/node1/servers/server1/ejb/webbank/Account
– Corbaname -- corbaname::myhost1:9812/NameServiceServerRoot#ejb/webbank/Account
The binding you can use to look up an object depends on whether or not the application is running within the same application server.
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JNDI - Federated namespace
The system partition is a reflection of the cell topology and is read-only. This part of the name space cannot be changed programmatically, because it is based on the configuration rather than runtime settings.
The persistent partitions are primarily for the storage of resource configuration, such as data sources, JMS destinations etc.
Cell persistent root. This partition is used to register persistent objects that are available to all the nodes and managed processes of a cell.
Node persistent root. This partition is used to register persistent objects available to the nodes and it their managed processes.
The server root transient partition is updateable through APIs, and is meant for information such as EJB bindings and JNDI names. This name space is transient and bindings are created each time a server process starts. It reads configuration data from the file system, for example EJB deployment descriptors, to register the necessary objects in this space.
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JNDI example (1)
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JNDI example (2)
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JDBC Resource
A data source represents a real-world data source, such as a relational database. When a data source object has been registered with a JNDI namingservice, an application can retrieve it from the naming service and use it to make a connection to the data source it representsInformation about the data source and how to locate it, such as its name, the server on which it resides, its port number, and so on, is stored in the form of properties on the DataSource object. This makes an application more portable because it does not need to hard code a driver name, which often includes the name of a particular vendorThe connection is usually a pooled connection. That is, once theapplication closes the connection, the connection is returned to a connection pool, rather than being destroyed.Data source classes and JDBC drivers are implemented by the datasource vendor.
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JDBC Resource
The programming model for accessing a data source is as follows:– 1. An application retrieves a DataSource object from the JNDI naming space.
– 2. After the DataSource object is obtained, the application code calls getConnection() on the data source to get a Connection object. The connection is obtained from a pool of connections.
– 3. Once the connection is acquired, the application sends SQL queries or updates to the database.
– 4. Once the application component is finished with the connection, it calls the close() method on the connection. Closing a connection handle should not close the physical connection to the EIS.
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JDBC Resource
In WebSphere Application Server, connection pooling is provided by two parts, a JCA Connection Manager and a relational resource adapter
The JCA Connection Manager provides connection pooling, local transaction, and security support
The relational resource adapter provides JDBC wrappers and the JCA CCI implementation that allows BMP, JDBC applications, and CMP beans to access the database
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JDBC Resource – Connection Pooling
WebSphere® Application Server provides connection pooling for Java Database Connectivity (JDBC), Java™ Message Service (JMS), and Enterprise Information System (EIS) connections.
The purpose of pooling connections is to improve performance by reducing the overhead involved in creating a new connection every time the application requests one.
For JDBC connections, there is one connection pool for each data source that is created in WebSphere Application Server
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Web Services for J2EE (JAX-RPC and WSEE)
JAX-RPC (JSR-101) provides the programming model for SOAP-based applications by abstracting the runtime details and providing mapping services between Java and WSDL.
Web Services for J2EE Specification (WSEE JSR-109) adds additional artifacts to those defined by JAX-RPC and brings JAX-RPC to the J2EE container.
WSEE defines the required architecture for Web services for the Java 2 Platform Enterprise Edition (J2EE) environment.
WSEE standardizes the packaging, deployment, and programming model for Web services in a J2EE environment.
Although WSEE does not restrict any implementation, it only defines two:– Stateless session EJB in an EJB container
– Java class running in a Web container
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JAX-RPC Client
A JAX-RPC client is capable of invoking a Web service irrespective of whether the service has been defined on the J2EE platform or on a non-Java platform.
JAX-RPC clients can run inside a J2EE container or as a stand-alone Java client.
There are three types of Web services clients:– Static stub
– Dynamic proxy
– Dynamic invocation interface (DII)
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JAX-RPC Client – Static Stub
After the proxy classes have been generated, they are copied to the client machine. The client can then invoke the Web service based only on these proxy classes.
These proxy classes are generated from the WSDL of the Web service.– In WebSphere Application Server, the proxy classes can be generated by the tool
<WAS_HOME>/bin/WSDL2JAVA.
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JAX-RPC Client – Static Stub, calling sequence
1. The client instantiates the service locator (WeatherForecastServiceLocator.java)
2. The client calls the service locator to retrieve the Service Endpoint Interface (an instance of the client stub that implements the SEI is returned).
3. The client invokes a Web service through the SEI.
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WSEE Client – Static Stub, calling sequence
1. The client makes an JNDI lookup to get an instance of the service object,which implements a service interface.2. The client uses a factory method of the service object to retrieve the clientstub. The client stub implements the SEI.3. The client invokes the Web service through the SEI.
The configurations for the Web service client and server side are represented bythe client and server deployment descriptor shown at the bottom
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JAX-RPC Client – Dynamic Proxy and DII
Dynamic Proxy
In dynamic proxy clients, the default destination of the Web service can be changed in the client by specifying a different destination in the client application.
At runtime the service locator is instantiated. The SEI is retrieved using a destination (QName).
Dynamic invocation interface (DII) - (limited support in WAS)
DII is used when the WSDL of the Web service can change considerably over time. DII-based clients do not use proxy classes, but instead they read the entire WSDL file during runtime:
– Instantiate a DII service class.
– Instantiate a Call object (Call is a class provided by JAX-RPC).
– Populate the Call object.
– Invoke the Web service operation on the Call object.
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WSEE Server Container responsability
A server container provides a JAX-RPC runtime environment for invoking Web services ports. The container is responsible for:
– Listening to Web services SOAP HTTP requests
– Parsing the inbound message
– Mapping the messages to the implementation class and method
– Creating Java objects from the SOAP envelope
– Invoking the service implementation bean handlers and instance methods
– Capturing the response
– Mapping the Java response objects into a SOAP message
– Creating the message envelope
– Sending the message to the client
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SOAP over HTTP request
The client request to the Java proxy is handled by the SOAP client and is routed to the server over HTTP.
In the server, the WebSphere SOAP engine calls a JavaBean Web service as a servlet, or uses a servlet in a Web router module to invoke an EJB Web service.
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References
http://www.redbooks.ibm.com