spiff-arena/tests/SpiffWorkflow/data/spiff/control-flow/critical_section.xml

<?xml version="1.0" encoding="UTF-8"?> 
<process-definition name="flow" revision="1.0">
    <description>Pattern 39 (Critical Section)</description>

    <!-- Start with an implicit simple split. -->
    <start-task>
        <successor>one_1</successor>
        <successor>two_1</successor>
    </start-task>

    <!-- Branch 1 -->
        <task name="one_1">
            <lock>lock_one</lock>
            <successor>one_2</successor>
        </task>
        <acquire-mutex name="one_2" mutex="my_global_mutex">
            <lock>lock_two</lock>
            <successor>one_3</successor>
        </acquire-mutex>
        <task name="one_3">
            <lock>lock_three</lock>
            <successor>two_2</successor>
            <successor>one_4</successor>
        </task>
        <release-mutex name="one_4" mutex="my_global_mutex">
            <lock>lock_four</lock>
            <successor>last</successor>
        </release-mutex>
    <!-- End branch 1 -->

    <!-- Branch 2 -->
        <task name="two_1">
            <successor>two_2</successor>
        </task>
        <acquire-mutex name="two_2" mutex="my_global_mutex">
            <successor>two_3</successor>
        </acquire-mutex>
        <task name="two_3">
            <successor>two_4</successor>
        </task>
        <release-mutex name="two_4" mutex="my_global_mutex">
            <successor>last</successor>
        </release-mutex>
    <!-- End branch 2 -->

    <!-- A final task. -->
    <task name="last">
        <successor>end</successor>
    </task>
</process-definition>