Built-in activities reference

• action
• GET
• POST
• PUT
• DELETE
• receivePOST
• replyPOST
• Receive-replyPOST
• receiveGET
• replyGET
• receive-replyGET
• while
• for-each
• pick
• assign
• empty

Action

The Action activity is a generic activity for calling a static operation on a Java™ class. The inputs form the parameters.

<action name="NCName" target="java-class-name" operation="NCName" outputVariable? >
  control*
  input*
</action>

The following example shows the action activity in tooling:

GET

This activity performs an HTTP GET. It has no input. Its output is the value of the response returned from the service.

<GET target="url-exp" name="NCName" outputVariable="NCName"? >
  control*   
</GET>

The following example shows the GET activity in the Assemble tooling:

You can find an example of the GET activity in the employee demo. See the flow samples for more information.

POST

The POST activity performs an HTTP POST. It has, at most, one input: the body of the post request. Its output is the value of the response returned from the service.

<POST target="url-exp" name="NCName" outputVariable="NCName"? >
  control* 
  input? 
</POST>

The following example shows the POST activity in the Assemble tooling:

You can find an example of the POST activity in the employee demo. See the flow samples for more information.

PUT

The PUT activity performs an HTTP PUT. It has, at most, one input: the body of the put request. Its output is the value of the response returned from the service.

<PUT target="url-exp" name="NCName" outputVariable="NCName"? >
  control* 
  input? 
</PUT>

The following example shows the PUT activity in the Assemble tooling:

DELETE

The DELETE activity performs an HTTP DELETE. It has no input or output.

<DELETE target="url-exp" name="NCName">
  control* 
</DELETE>

The following example shows the DELETE activity in the Assemble tooling:

You can find an example of the DELETE activity in the employee demo. See the flow samples information for details.

ReceivePOST

A receive activity consumes HTTP POST requests sent to the process and matches its optional URL fragment. Note that no two receive activities with the same operation and url value can be activated at the same time.

The output of a receive is the value of the received message. It has no input.

<receivePOST name="NCName" url="relative-url"? outputVariable="NCName"? >
   control*
</receivePOST>

ReplyPOST

A replyPOST activity provides the response to an HTTP POST request previously matched to a receive activity. At the point the reply activity runs, there MUST be exactly one outstanding receive activity with a matching operation name or a URL value, or both. An outstanding receive activity is one that has been matched to an incoming request but for which a response has not yet been produced.

The input is the value sent in the response. It has no output and, at most, one input. The value of the input is what is sent in the response.

<replyPOST url="relative-url"? view="view"? redirect="redirect-url"? outputUri="GC_URI"? name="NCName">
  control*
  input?
</replyPOST>

You can find this sample in the report demo of the flow samples information.

Receive-replyPOST

A receive-replyPOST activity is a combination of a receivePOST immediately followed by a replyPOST. Its output is the value of the received message. Its input is the same as reply: the value sent in the response.

<receive-replyPOST url="relative-url"? outputVariable="NCName"? redirect="redirect-url"? name="NCName">
  control*
  input?
</receive-replyPOST>

receiveGET, replyGET, and receive-replyGET

These activities are similar to their POST counterparts, but for HTTP GET instead of HTTP POST.

While

This activity is a structured loop. The condition is evaluated when the loop is activated. If the condition is true, the activities inside the loop are activated (respecting the order of specified by their links). When all activities inside the loop have completed or disabled, the condition is evaluated again. This repeats until the condition evaluates to false, at which point navigation continues based on the links leaving the while activity itself. No links can cross the boundaries of a while loop.

This activity has no input and no output variable.

<while name="NCName" condition="bool-expr">
   control*
   activity+
</while>

The following sample shows the sum of all integers ranging from 1 to 99.

<process name="sample" expressionLanguage="Groovy">

      <variable name="i" value="${1}"/>   
      <variable name="sum" value="${0}"/>
      
      <while name="while" condition="i &lt; 100 ">
         <assign name="addI">
            <copy from="${sum+i}" to="sum" />
         </assign>
         
         <assign name="increaseI">
            <copy from="${i+1}" to="i" />
         </assign>           
      </while>
      
      <replyGET name="reply">   
        <control source="while"/>
        <input value="${sum}"/>
      </replyGET>
</process>

The following example shows the while activity in the Assemble tooling:

for-each

The foreach activity iterates elements of one list, and performs processing against each of them. It takes a list as input and has nested activities operating on each item in the list. It has no output. Its syntax is shown in the following example:

<for-each name="NCName" itemName="..."? >
   input 
   control*
   <activity>+
</for-each>

The following sample shows a sum of the list [1, 3, 5, 7].

<process expressionLanguage="Groovy" name="add">
   <variable name="n" value="${0}" />
   <variable name="list" value="${[1, 3, 5, 7]}"/>
    <for-each name="foreach" itemName="i">
        <input value="${list}"/>
       <assign name="sum">
          <copy to="n" from="${n + i}"/>
       </assign> 
    </for-each>
   <replyGET name="reply">
       <control source="foreach"/>
       <input value="${n}"/>
   </replyGET>
</process>

The result of this flow is 16.

The following example shows the for-each activity in the Assemble tooling:

Pick

A pick activity provides external choice. It contains a variable name and an ordered list of choices, each one corresponding to an external request.

It has no input. Its output is a variable consisting of two parts:

choice

The name or index of the choice that is picked.

message

The value of the message received by the picked choice, if any.

The first event to occur is the one chosen to determine the value of the choice in the pick's output variable: either the name of the choice if one is present, or the numerical index of the choice. If the choice is based on an incoming message, then the incoming message's body is placed in the message part of the pick's output variable. If the choice itself also specifies a variable, then a copy is placed in that variable as well. You can branch on the choice made in the pick using the value of the choice part of the variable in conditions of links.

<pick name="NCName" outputVariable="NCName"? >
   control*
   <choice name="NCName"? url="relative-url-exp"? outputVariable="NCName"? /> +
</pick>

Assign

Assignment allows initialization of variables and copying of values from one variable to another.

The assign activity provides a simple data copying utility. It contains one or more copy elements. The assign activity has no semantics, other than to execute its embedded copy elements in sequence. In particular, there is no implication of atomic behavior or roll-back capabilities.

As an assign can copy from and to multiple locations, it has no implicit input or output. Variables that it reads from and writes to must be explicitly referenced in the body of the activity.

<assign name="NCName">
   control* 
   <copy from="expression"? to="expression" >from-expression?</copy>+
</assign>

The following sample changes a Yahoo!® top music RSS feed title text with an appended publish date:

<process expressionLanguage="Groovy" name="feedSample">
	<receiveGET name="start"/>
	<GET name="album" target="http://rss.music.yahoo.com/charts/rssTopAlbums.xml"/>
	
	<assign name="changeTitle">
		<copy from="${album.channel.title[0].textContent + album.channel.pubDate[0].textContent}" to="album.channel.title[0].textContent" />
	</assign>
	
	<replyGET name="result">
		<control source="changeTitle" />
		<input value="${album}" />
	</replyGET>
</process>

The processor can create some of the structure of the "to" attribute if it does not already exist.

The following example shows the assign activity in the Assemble tooling:

Empty

The empty activity implies no processing other than the navigation implied by its connection to other activities through links. It is provided for the purpose of helping the creation of specific navigational patterns.

The output of an empty activity is null. It has no input.

<empty name="NCName">
  control*
</empty>