14.1 Introduction to Event and Timeout Concepts This chapter provides an example of how to program a BPEL process service component to wait one minute for a response from a web service named Star Loan that provides loan offers. If Star Loan does not respond in one minute, then the BPEL process service component automatically selects an offer from another web service named United Loan. In the real world, the time limit is more like 48 hours. However, for this example, you do not want to wait that long to see if your BPEL process service component is working properly. Because asynchronous web services can take a long time to return a response, a BPEL process service component must be able to time out, or give up waiting, and continue with the rest of the flow after a certain amount of time. You can use a pick activity to configure a BPEL flow to either wait a specified amount of time or to continue performing its duties. To set an expiration period for the time, you can use the wait activity. 14.2 Creating a Pick Activity to Select Between Continuing a Process or Waiting The pick activity provides two branches, each one with a condition. The branch that has its condition satisfied first is executed. In the following example, one branch's condition is to receive a loan offer, and the other branch's condition is to wait a specified amount of time. Provides an overview. BPEL is a programming language, and activities provide functions and operations for creating a BPEL process web service. Understanding the purpose and usage of the activities are very important for creating a BPEL process to serve a business function. We use this activity in following cases. When we call asynchronous service and we need response back in certain time frame otherwise we need to throw exception. When we want to have multiple entry point for any composite. For an incoming message using a BPEL receive or pick activity • Waiting for a. Another service • Before a wait For example, a BPEL process may be waiting for. In the event of server instance failure, a BPEL process will resume execution. The following activities take place (in order of priority): • An invoke activity initiates a service, in this case, a request for a loan offer from Star Loan. • The pick activity begins next. It has the following conditions: • onMessage This condition has code for receiving a reply in the form of a loan offer from the Star Loan web service. The onMessage code matches the code for receiving a response from the Star Loan web service before a timeout was added. • onAlarm This condition has code for a timeout of one minute. This time is defined as PT1M, which means to wait one minute before timing out. In this timeout setting: • S stands for seconds • M for one minute • H for hour • D for day • Y for year In the unlikely event that you want a time limit of 1 year, 3 days, and 15 seconds, you enter it as PT1Y3D15S. The remainder of the code sets the loan variables selected and approved to false, sets the annual percentage rate (APR) at 0.0, and copies this information into the loanOffer variable. The time duration format is specified by the BPEL standard. For more detailed information on the time duration format, see the duration section of the most current XML Schema Part 2: Datatypes document at: • The pick activity condition that completes first is the one that the BPEL process service component executes. The other branch then is not executed. Figure 14-1 Overview of the Pick Activity An onMessage branch is similar to a receive activity in that it receives operations. However, you can define a pick activity with multiple onMessage branches that can wait for similar partner links and port types, but have different operations. Therefore, separate threads and parallel processes can be invoked for each operation. This differs from the receive activity in which there is only one operation. Another difference is that you can create a new instance of a business process with a receive activity (by selecting the Create Instance checkbox), but you cannot do this with a pick activity. Example 14-1 Pick Activity Expired false false 0.0. Aug 19, 2018 - Windows 10 Product Keys Generator Windows 8.1. Windows 8.1 Pro Activation key – GCRJD-8NW1H-F2CDX-CCM8D-1D1T1. Windows 8 pro build 9200 x64. I ran cmd as administrator, and typed slui.exe 3 and then entered activation key and when product key is accepted. I pressed activate. Jan 3, 2017 - free windows 8 pro product key, win8 pro activation code,win8 pro serial key. It comprises on built-in antivirus for phishing filtering for prevention of. You Might Alsolike: MS Office 2016 Professional Plus Key Free Download. ![]() Pick Activity In Bpel 11g Example Resumes![]() ![]() 14.2.3 What You May Need to Know About Simultaneous onMessage Branches in BPEL 2.0 Oracle BPEL Process Manager's implementation of BPEL 2.0 does not support simultaneous onMessage branches of a pick activity. When a process has a pick activity with two onMessage branches as its starting activity (both with initiate set to join in their correlation definitions) and an invoking process that posts the invocations one after the other, it is assumed that both invocations reach the same instance of the invoked process. However, in Oracle BPEL Process Manager's implementation of BPEL 2.0, two instances of the invoked process are created for each invocation. This is the expected behavior, but it differs from what is described in the BPEL 2.0 specification. For example, assume you have synchronous BPEL process A, which has a flow activity with two parallel branches: • Branch one invokes operation processMessage1 on asynchronous BPEL process B. • Branch two invokes operation processMessage2 on asynchronous BPEL process B. The invocation occurs after a five second wait. BPEL process A then waits on a callback from BPEL process B and returns the output back to the client. The idea is to create one instance of the invoked process and ensure that the second invocation happens after the first instance is already active and running. BPEL process B has a pick activity with createInstance set to yes. The pick activity has two onMessage branches within it: • One branch is for the processMessage1 operation. For this operation, it goes to sleep for about 10 seconds. • The other branch is for the processMessage2 operation. ![]() For this operation, it waits for five seconds. Both operations have the same input message type and correlation is defined with initiate set to join.The expectation is that the processMessage1 invocation is invoked immediately and the BPEL process B instance is created, which should sleep for ten seconds. After five seconds, the invoking process should then post the processMessage2 invocation to BPEL process B and this invocation should go to the already existing instance instead of creating a new one (since the correlation ID is the same and initiate is set to join). However, for each invocation, a new instance of BPEL process B is created and the result cannot be predicted. • If the processMessage2 operation branch finishes first, then the subsequent assign operation fails because the input variable from processMessage1 is assumed to be null (for that instance). • If the processMessage1 operation branch finishes first, then the process returns callback data with only partial information (does not include the input from processMessage2). In Oracle BPEL Process Manager's implementation, either one of the two operations (processMessage1 or processMessage2) creates a new instance. This is implemented so that database queries do not need to be made to see if there are already instances created. The workaround is to create two processes that are initiated by the two different operations. 14.3 Setting Timeouts for Request-Response Operations in Receive Activities You can provide a timeout setting for request-response operations in receive activities. This provides an alternative to using the onMessage and onAlarm branches of a pick activity to specify a timeout duration for partner callbacks. The following sections provide an overview of this functionality: • Timeout settings relative from activity invocation • Timeout settings as an absolute date time • Timeout settings computed dynamically with an XPath expression • bpelx:timeout fault thrown during an activity timeout • Events added to the BPEL instance audit trail during an activity timeout • Recoverable timeout activities during a server restart. Example 14-2 Timeout Settings Relative from When the Activity is Invoked standard-elements This type uses the bpelx:for attribute to specify a static value or an XPath expression that must evaluate to an XML schema type duration. Only one of the bpelx:for or bpelx:until attributes is permitted for an activity. If the XPath expression evaluates to a negative duration, the timeout is ignored and an event is logged to the instance audit trail indicating that the duration value is invalid. Once a valid duration value is retrieved, the expiration date for the activity is set to the current node time (or cluster time after this is available), plus the duration value. For example, the duration value bpelx:for='PT5M' specifies that the activity expects an inbound message to arrive no later than five minutes after the activity has started execution. Example 14-3 Timeout Settings as an Absolute Date Time standard-elements The expected expiration time for the bpelx:until attribute must be at least two seconds ahead of the current time.
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