Oracle Commerce Platform 11.1

dsp:sort

Sorts the contents of a Collection or an array.

<dsp:sort var-spec values="sort-item"
   [comparator="comparator-obj"]
   [reverse="{true|false}"]

>
   ...
</dsp:sort>

Attributes

var-spec

An EL variable or scripting variable that stores the sorted output, defined with one of these attributes:

Attribute	Description
`var`	Names an EL variable. When you use `var`, you can set its `scope` attribute to `page`, `request`, `session`, or `application`. The default scope is `page`. For more information, see EL Variable Scopes. By default, the values that are sorted into the `var`-specified object have the same data type as the source values. For example, sorting an array of strings produces another array of Strings. The EL variable has a number of properties that enable you to access the sorted output as a different data type. For more information, see Usage Notes below.
`id`	Names a scripting variable that scriptlets and expressions can access at runtime.

Attribute

Description

var

Names an EL variable. When you use var, you can set its scope attribute to page, request, session, or application. The default scope is page. For more information, see EL Variable Scopes.

By default, the values that are sorted into the var-specified object have the same data type as the source values. For example, sorting an array of strings produces another array of Strings.

The EL variable has a number of properties that enable you to access the sorted output as a different data type. For more information, see Usage Notes below.

id

Names a scripting variable that scriptlets and expressions can access at runtime.

values

Identifies the item to sort. This attribute can be set to items of the following data types:

array of primitives
array of objects
Enumeration
Iterator
Collection
Map

This attribute cannot be set to a Dynamic Bean or any items with Dynamic Bean properties to be used for sorting.

Array of objects
Array of primitives
Collection
Iterator
Enumeration
Map

The page processor sorts the contents of the specified item as follows, in descending order of precedence:

If the comparator attribute is set to a java.util.Comparator object, dsp:sort uses the sort instructions defined in the Comparator object.
dsp:sort uses the nested dsp:orderBy tags.
dsp:sort interprets the items in their natural order, when all items are of type java.lang.Comparable.

By default, the values that are sorted into the var-specified object have the same data type as the source values. For example, sorting an array of strings produces another array of Strings.

The EL variable has a number of properties that provide access to the sorted output as a different data type, shown in the table below. For example, the sortedMap property lets you render a Collection as a Map. The resultant Map holds the Collection items as keys.

Note: Rendering an item as a different data type slows site performance.

Sort variable properties

Sort property	Description
`sortedArray`	Renders the sorted item as an array.
`sortedBooleanArray`	Renders the sorted item as an array of Boolean objects.
`sortedByteArray`	Renders the sorted item as an array of Byte objects.
`sortedCharArray`	Renders the sorted item as an array of Char objects.
`sortedCollection`	Renders the sorted item as a Collection.
`sortedDoubleArray`	Renders the sorted item as an array of Double objects.
`sortedEnumeration`	Renders the sorted item as an Enumeration.
`sortedFloatArray`	Renders the sorted item as an array of Float objects.
`sortedIntArray`	Renders the sorted item as an array of Int objects.
`sortedIterator`	Renders the sorted item as an Iterator.
`sortedLongArray`	Renders the sorted item as an Array of Long objects.
`sortedMap`	Renders the sorted item as a Map.
`sortedShortArray`	Renders the sorted item as an array of Short objects.

The following table describes what happens when you convert items from one data type to another:

Original data type	Accessed as this data type	Example
Array of primitive values	Collection Iterator Enumeration Map array of objects	array of Strings > Collection: Collection of String objects
Collection array	Map	Enumeration of Longs > Map: Map with key entries that are Long objects
Map	Collection Iterator Enumeration Map array of objects	Map > Collection: Collection composed of Map key values
Collection Iterator Enumeration Map array of objects	Array of primitives	Iterator > Array of primitives: Null value
Array of primitives	Array of primitives of a different data type	array of ints > array of shorts: Array of short objects that are truncated versions of the original int values

Example

<dsp:importbean bean="/atg/samples/AdvancedAlgebra" var="advAlgebra"/> <dsp:sort var="sorter" values="${advAlgebra.students}"> <dsp:orderBy property="lastName"/> <c:forEach var="student" begin="0" items="${sorter.sortedMapArray}"> <dsp:tomap value="${student}" var="studentMap"/> <li>Name: <c:out value="${studentMap.lastName}"/>, <c:out value="${studentNap.firstName}"/> </c:forEach> </dsp:sort>

This example organizes the student roster for Advanced Algebra. The AdvancedAlgebra component has a Students property that is a Map of student last names and first names. In this example, the students are organized alphabetically by last name. Then, each student’s first name and last name are displayed.

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