<switch> - Business Process and Data Transformation Language Reference

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Ensemble Reference Material > Business Process and Data Transformation Language Reference > BPL Elements > <switch>

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Evaluate a set of conditions to determine which of several actions to perform.

Synopsis

<switch>   <case>     ...   </case>   ...   <default>     ...   </default> </switch>

Details

Attribute or Element	Description
name, disabled, xpos, ypos, xend, yend attributes	See “Common Attributes and Elements.”
<annotation> element	See “Common Attributes and Elements.”
<case> element	Required (at least one). Each <case> element defines a condition that may or may not be true.
<default> element	Optional. Specifies the action to take if no <case> condition is satisfied. If present, must appear last in the <switch> element.

Description

The <switch> element contains a sequence of one or more <case> elements and an optional <default> element.

When a <switch> element is executed, it evaluates each <case> condition in turn. These conditions are logical expressions in the scripting language of the containing <process> element. If any expression evaluates to the integer value 1 (true), then the contents of the corresponding <case> element are executed; otherwise the expression for the next <case> element is evaluated.

If no <case> condition is true, the contents of the <default> element are executed.

As soon as one of <case> elements is executed, execution control leaves the surrounding <switch> statement. If no <case> condition matches, control leaves the <switch> after the <default> activity executes.

If no <case> is true and there is no <default>, no activity results from the <switch> statement.

Activities within a <case> element can be any BPL activity, including <assign> elements as in the example below:

<switch name='Approved?'>
  <case name='No PrimeRate' condition='context.PrimeRate=""'>
    <assign name='Not Approved' property="response.IsApproved" value="0"/>
  </case>
  <case name='No Credit' condition='context.CreditRating=""'>
    <assign name='Not Approved' property="response.IsApproved" value="0"/>
  </case>
  <default name='Approved' >
    <assign name='Approved' property="response.IsApproved" value="1"/>
    <assign name='InterestRate'
            property="response.InterestRate"
            value="context.PrimeRate+10+(99*(1-(context.CreditRating/100)))">
      <annotation>
        <![CDATA[Copy InterestRate into response object.]]>
      </annotation>
    </assign>
  </default>
</switch>