[SLING-10677] add support for using an enum class via the Java Use-API

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: Scripting HTL Engine 1.4.12-1.4.0
• Component/s: Scripting
• Assignee: Eric Norman
• Reporter: Eric Norman
• Created: 27/Jul/21 23:04
• Updated: 11/Aug/21 20:32
• Resolved: 07/Aug/21 21:21

Description

For a use case where you need access to an enum value in your ui script for some reason, it would be nice to be able to "data-sly-use" your enum class with something like this:

 

<sly data-sly-use.myEnum="org.hello.MyEnum"></sly>

... and then later on you can reference the enum values with an expression that looks something like this:

<p>
 Enum value by name: ${myEnum.SOMEVALUE}
</p>
<p>
 Enum value by ordinal: ${myEnum[1]}
</p>
<p>
 Constant static field within the enum: ${myEnum.SOME_NON_VALUE_CONSTANT_FIELD}
</p>

<p data-sly-repeat.value="${myEnum.values}">
     Enum value[${value.ordinal}] from static method call: ${value}
</p>

Since the enum can not have a default constructor, special handling in JavaUseProvider would be required to return the enum class itself instead of trying to instantiate a new instance of the class.

 

NOTE: A companion fix will also be required in org.apache.sling.scripting.sightly.render.ObjectModel#resolveProperty to deal with the target object being an Enum class instead of a POJO object in order for the expressions to resolve as expected.

Issue Links

• relates to: SLING-10678 enhance ObjectModel#resolveProperty to handle target that is an enum class
• links to: PR #8
• links to: PR #13

Sub-Tasks

• add integration content for testing: Closed
• add integration tests to verify: Closed