OpenTestSystem.Otx.Core.Nodes.Node.CompoundNode.Loop.LoopRealisation.LoopConfigurationHeader.LoopConfigurationRealisation.ForEachLoop Class Reference

Loop over a collection. More...

Inheritance diagram for OpenTestSystem.Otx.Core.Nodes.Node.CompoundNode.Loop.LoopRealisation.LoopConfigurationHeader.LoopConfigurationRealisation.ForEachLoop:

Public Attributes
CollectionTerm	collection
	Cardinality [0..1] List or Map over which the for-each-loop iterates. More...
Variable	locator
	Cardinality [0..1] This element must be an Integer or String Variable that will be used as the locator variable of the for-each-loop. More...
Variable	value
	Cardinality [0..1] This element points to a variable that shall hold the list items or map values. More...

Detailed Description

Loop over a collection.

The for-each-loop is configured by a collection (a List or a Map) and a so called locator variable. The collection is expressed by a List or Map expression which shall be evaluated initially. The flow of the loop shall be executed repeatedly for each item found in the collection. The current item of an iteration can be accessed by using the locator variable which contains the index or key of the List or Map item, respectively. Like this, the current item can be used for any kind of computation in the loop flow.

Note

If the collection is a List, there is a defined order for the iterations: The loop starts with the first List item (index 0), followed the second item and so on. By contrast, there is no particular order defined for Map.

Since a locator variable is visible procedure-wide, it is accessible on the outside of the loop as well.

When entering a for-each-loop, the old value of the locator variable shall be overwritten implicitly by the index/key of the first item of the List or Map. Similarly, the old value of the value variable shall be overwritten implicitly by the first item/value. After leaving the loop, the locator variable value of the final iteration will be visible to the follower nodes of the loop node.

Actions derived from ListModifier and MapModifier are collection modifiers. Since they can change a List length or Map size, applying such modifications on a for-each-loop's collection during loop execution may cause serious inconsistencies (e.g. when a collection item is accessed which does not exist anymore). Therefore OTX runtime will throw ConcurrentModificationException when such modifications occur. By contrast, changing the value of items of a for-each-loop's collection does not represent a concurrent modification and will not cause a ConcurrentModificationException.

Syntax

foreach (Variable locator, Variable value in CollectionTerm collection) : LoopName
{
    ...
}
 
foreach (Variable locator, CollectionTerm collection) : LoopName
{
    ...
}
 
foreach (Variable value in CollectionTerm collection) : LoopName
{
    ...
}

Examples

// Local Declarations
List<Integer> Collection1 = {1, 2, 3};
Integer Locator1;
Integer Value1;
Integer ValueAtLocator;
Integer ValueOfValue;
 
// Flow
foreach (Locator1, Value1 in Collection1) : ForEachLoop1
{
    ValueAtLocator = Collection1[Locator1];
    ValueOfValue = Value1;
}
 
foreach (Locator1, Collection1) : ForEachLoop2
{
}
 
foreach (Value1 in Collection1) : ForEachLoop3
{
}

Checker rules

CheckerRule.Core_Chk014 - Correct locator variable type in for-each-loop
CheckerRule.Core_Chk056 - No modification of collection inside foreach-loops
CheckerRule.Core_Chk063 - Locator or value in for-each-loop
CheckerRule.Core_Chk064 - Correct value variable type in for-each-loop

Exceptions

Exceptions.ConcurrentModificationException

It is thrown in case that the collection is modified while the loop is active. Modifications can be triggered by actions inside of the loop or from the outside, e.g.by actions in a parallel lane.

Member Data Documentation

collection

CollectionTerm OpenTestSystem.Otx.Core.Nodes.Node.CompoundNode.Loop.LoopRealisation.LoopConfigurationHeader.LoopConfigurationRealisation.ForEachLoop.collection

Cardinality [0..1]
List or Map over which the for-each-loop iterates.

locator

Variable OpenTestSystem.Otx.Core.Nodes.Node.CompoundNode.Loop.LoopRealisation.LoopConfigurationHeader.LoopConfigurationRealisation.ForEachLoop.locator

Cardinality [0..1]
This element must be an Integer or String Variable that will be used as the locator variable of the for-each-loop.

value

Variable OpenTestSystem.Otx.Core.Nodes.Node.CompoundNode.Loop.LoopRealisation.LoopConfigurationHeader.LoopConfigurationRealisation.ForEachLoop.value

Cardinality [0..1]
This element points to a variable that shall hold the list items or map values.