{"id":3418,"date":"2012-06-19T16:13:15","date_gmt":"2012-06-19T21:13:15","guid":{"rendered":"http:\/\/jianmingli.com\/wp\/?p=3418"},"modified":"2012-07-05T13:02:21","modified_gmt":"2012-07-05T18:02:21","slug":"1z0-451-orchestrating-services-with-bpel","status":"publish","type":"post","link":"https:\/\/jianmingli.com\/wp\/?p=3418","title":{"rendered":"1Z0-451: Orchestrating Services with BPEL"},"content":{"rendered":"

This is part of 1Z0-451: Oracle SOA Foundation Practitioner Exam<\/a><\/p>\n

Explain BPEL Components activities and partner Links<\/h2><\/span>\n

Activities<\/h3><\/span>\n

* Activities are the building blocks of a BPEL process service component.
\n* Activities perform specific tasks within a BPEL process service component.
\n* Activities can be dragged into a BPEL process using BPEL Designer.
\n* See this post<\/a> for a list of BPEL activities.<\/p>\n

Partner Links<\/h3><\/span>\n

See Introduction to Partner Links<\/a>
\n* A partner link defines
\n– an external service<\/strong> with which the BPEL process is to interact.
\n– a conversational relationship between two services by defining roles played by each service.
\n* Can be defined as
\n– services
\n– references (e.g. JCA adapter)
\n* Can be defined in
\n– composite editor (preferred)
\n– BPEL editor (still need to wire in composite diagram)
\n* Dialog fields:
\n– Name
\n– Process
\n– WSDL URL
\n– Partner link type
\n– Pertner role
\n– My role (for asynch only)<\/p>\n

Describe Synchronous and Asynchronous BPEL Processes<\/h2><\/span>\n

Synchronous Interactions<\/h3><\/span>\n

* Client sends a message to the service and receives an immediate reply.
\n* Uses a reply <\/strong>activity to respond to the client.<\/p>\n

Asynchronous Interactions<\/h3><\/span>\n

* A client sends a request to a service and waits until the service replies.
\n* Uses an invoke <\/strong>activity to respond to the client.<\/p>\n

Describe Message Transformations and XSLT<\/h2><\/span>\n

* See here <\/a>for details.
\n* You use the XSLT Mapper to create the contents of a map file.<\/p>\n

Explain Parallel Flow and Conditional branching<\/h2><\/span>\n

* See
\n– Using Parallel Flow in a BPEL Process<\/a>
\n– Using Conditional Branching in a BPEL Process<\/a><\/p>\n

Parallel Flow<\/h3><\/span>\n

* Enables a BPEL process service component to perform multiple tasks at the same time.
\n* Especially useful when you must perform several time-consuming<\/strong> and independent <\/strong>tasks.
\n* Created by Flow Activity<\/strong>.
\n* Use parallel flow Links <\/strong>to
\n– synchronize between activities from different flows.
\n– provide dependencies between parallel flow activities.
\n* Use optional join condition<\/strong> in target activities to create join condition (logical AND <\/strong>operation).
\n– defaults to no join<\/strong> (logical OR <\/strong>operation).<\/p>\n

Control Number of Parallel Branches<\/h4><\/span>\n

* Use FlowN <\/strong>for BPEL 1.1 project.
\n– For example, if the array contains 3 elements, N is set to 3. Assuming the index variable begins at 1, the flowN activity creates three parallel branches with indexes 1, 2, and 3.
\n* Use forEach <\/strong>for BPEL 2.0 project.
\n– Executes a child scope activity exactly N+1<\/strong> times, where N = (final counter value) – (starting counter value).
\n– Can only include a single child scope <\/strong>activity.
\n– Support both sequential (default) and parallel (use Parallel Execution checkbox) iterations.
\n– A completion condition<\/strong> can be specified on the Completion <\/strong>tab. Once completion condition is evaluated to true, the loop is terminated.<\/p>\n

Conditional branching<\/h3><\/span>\n

* Use switch <\/strong>activity in BPEL 1.1 project.
\n* Use if <\/strong>activity in BPEL 2.0 project.
\n– if-elseif-else
\n* Instead of using conditional branching, use skipCondition <\/strong> (an XPath expression) to bypass the execution of a particular activity.<\/p>\n

While Activity<\/h4><\/span>\n

* The while loop repeats an activity until a specified success criteria is met.
\n* Instead of the while activity, use repeatUtil <\/strong>if the body of an activity must be performed at least once<\/strong>.<\/p>\n

Explain BPEL integration with Java<\/h2><\/span>\n

* See
\n– Incorporating Java and Java EE Code in a BPEL Process<\/a><\/p>\n

Methods for Incorporating Java and Java EE code in BPEL Processes<\/h3><\/span>\n

* Wrap as a SOAP service.
\n– Performance hit.
\n– Loss of transactionality.
\n* Embed Java code snippets into a BPEL process with the bpelx:exec tag.
\n– Better performance.
\n– Retain transactionality.
\n– BPEL 2.0 uses Java Embedding<\/strong> Activity to execute Java code snippets.
\n* Use an XML facade to simplify DOM manipulation.<\/p>\n

Built-in bpelx:exec Methods<\/h4><\/span>\n

* Object lookup( String name ) \/\/ JNDI access
\n* long getInstanceId( ) \/\/Unique ID associated with each instance
\n* String setTitle( String title ) \/ String getTitle() \/\/ Title of this instance
\n* String setStatus( String status ) \/ String getStatus() \/\/ Status of this instance
\n* void setCompositeInstanceTitle(String title) \/\/ Set the composite instance title
\n* void setIndex( int i, String value ) \/ String getIndex( int i )
\n* void setCreator( String creator ) \/ String getCreator() \/\/ Wo initiated this instance
\n* void setCustomKey( String customKey ) \/ String getCustomKey() \/\/ Second primary key
\n* void setMetadata( String metadata ) \/ String getMetadata () \/\/ Metadata for generating lists
\n* String getPreference( String key ) \/\/ Access preference
\n* void addAuditTrailEntry(String message, Object detail) \/\/ Add an entry to the audit trail
\n* void addAuditTrailEntry(Throwable t) \/\/ Access file stored in the suitcase
\n* Object getVariableData(String name) throws BPELFault \/\/ Access variables stored in the scope
\n* Object getVariableData(String name, String partOrQuery) throws BPELFault \/\/ Access variables
\n* Object getVariableData(String name, String part, String query) \/\/ Access variables
\n* void setVariableData(String name, Object value)
\n* void setVariableData(String name, String part, Object value)
\n* void setVariableData(String name, String part, String query, Object value)<\/p>\n

Tips<\/h4><\/span>\n

* Use Wait Activity<\/strong> instead of thread.sleep()<\/strong> in a Java code.
\n– Releases resource upon entering the wait activity.
\n– Enables ongoing transaction to commit.
\n– Instance data is hydrated into data store.<\/p>\n

Adding Custom Classes and JAR Files<\/h4><\/span>\n

* Add to extenstion library
\n– For WebLogic server, add to: $ORACLE_HOME\/soa\/modules\/oracle.soa.ext_11.1.1<\/strong>
\n– For JDev add to: application_name\/project\/sca-inf\/lib<\/strong>
\n* Add JARs to BpelcClasspath
\n– SOA Infrastructure > SOA Administration > BPEL Properties > More BPEL Configuration Properties > BpelcClasspath<\/strong>.
\n* Add custom classes:
\n– Copy to classes directory.
\n– Restart WebLogic server.
\n* Add cusotm JARs:
\n– Copy to directory
\n– Run ant ???
\n– Restart WebLogic server.<\/p>\n

Next>> Advanced BPEL Concepts<\/a><\/p>\n

References<\/h2><\/span>\n

* Using the BPEL Process Service Component<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

This is part of 1Z0-451: Oracle SOA Foundation Practitioner Exam Explain BPEL Components activities and partner Links Activities * Activities are the building blocks of a BPEL process service component. * Activities perform specific tasks within a BPEL process service … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[107,100],"tags":[],"class_list":["post-3418","post","type-post","status-publish","format-standard","hentry","category-certification","category-soa11g"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p8cRUO-T8","_links":{"self":[{"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=\/wp\/v2\/posts\/3418","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3418"}],"version-history":[{"count":17,"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=\/wp\/v2\/posts\/3418\/revisions"}],"predecessor-version":[{"id":4967,"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=\/wp\/v2\/posts\/3418\/revisions\/4967"}],"wp:attachment":[{"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3418"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3418"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3418"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}