OCL Collection Operators
This page was created by Stephanie on 2025-03-10. Last edited by Stephanie on 2025-03-10.
Once you have a collection of objects, there are certain operators applicable to them.
You can use the OCL-Editor to see what they are:
Operators | Description |
---|---|
->append | Add another object last |
->asBag | Returns a Bag containing all elements of self. |
->asSequence | Returns a Sequence containing all elements of self. Element ordering is preserved when possible. |
->asSet | Returns a Set containing all elements of self. |
->at | Get the objects at X where the first index is 1 |
->at0 | Get the objects at X where the first index is 0 |
->collect | Returns a collection containing the result of applying expr on all elements contained in self. |
->count | Count how many meet a certain criteria |
->dictionary | Efficiently looks up values |
->difference | The difference between 2 collections |
->excluding | The collection except for this single object |
->exists | Returns true if at least one element in self validates the condition expr, false otherwise. |
->filterOnType | Only keep the ones of a certain type |
->first | Return the first object |
->forAll | Returns true if all the elements contained in self validate the condition expr, false otherwise. |
->groupBy | Build a collection of tuples grouped by some aspect |
->includes | Does the collection include the object |
->includesAll | Does the collection include the whole other collection |
->including | Returns the list with the element in the parameter included. |
->IndexOf | The 1 based index of an object in the collection possibly -1 if not existing |
->indexOf0 | The 0 based index of an object in the collection possibly -1 if not existing |
->intersection | The intersection of two collections |
->isEmpty | Returns true if the collection is empty |
->notEmpty | Returns true if self contains at least one element, false otherwise. |
->reject | Returns a collection with all elements of self except for those who validate the OclExpression expr. |
->select | Returns a collection with all elements of self that validate the OclExpression expr. |
->size | Returns the number of elements contained in self. |
->sum | Returns the sum of all elements contained in self if they support the '+' operation. |
->last | Returns the last object in the collection |
->orderBy | Sorts the collection on one or more properties |
->orderDescending | Sort the from biggest to smallest |
->orderGeneric | Sorts the list of properties with interchangeable sort order: (expr1, OclSortDirection::ascending, expr2, OclSortDirection::descending...) |
->prepend | Returns an OrderedSet containing object followed by all elements of self. |
->subsequence | Returns a smaller collection from a start to stop |
->symmetricDifference | The symmetric difference between the collections; ie all the objects in collection1 or collection2 but not in both |
->union | The set of objects in collection1 and objects in collection2 |
See this page for examples on collection operators.
Also check out: OCLOperators