(causeway) branch master updated: CAUSEWAY-3649: ActionInteractionWkt: adds safe guard against access to the model while it is not attached

[ahuber]

This is an automated email from the ASF dual-hosted git repository.

ahuber pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/causeway.git


The following commit(s) were added to refs/heads/master by this push:
     new f89ad01051 CAUSEWAY-3649: ActionInteractionWkt: adds safe guard 
against access to the model while it is not attached
f89ad01051 is described below

commit f89ad0105157c967d35ce8e3310d2a5b07dc636f
Author: Andi Huber <ahu...@apache.org>
AuthorDate: Tue Nov 21 18:59:23 2023 +0100

    CAUSEWAY-3649: ActionInteractionWkt: adds safe guard against access to
    the model while it is not attached
---
 .../interaction/act/ActionInteractionWkt.java      | 44 ++++++++++++++++------
 1 file changed, 32 insertions(+), 12 deletions(-)

diff --git 
a/viewers/wicket/model/src/main/java/org/apache/causeway/viewer/wicket/model/models/interaction/act/ActionInteractionWkt.java
 
b/viewers/wicket/model/src/main/java/org/apache/causeway/viewer/wicket/model/models/interaction/act/ActionInteractionWkt.java
index 5a21cbf249..4c043bc24e 100644
--- 
a/viewers/wicket/model/src/main/java/org/apache/causeway/viewer/wicket/model/models/interaction/act/ActionInteractionWkt.java
+++ 
b/viewers/wicket/model/src/main/java/org/apache/causeway/viewer/wicket/model/models/interaction/act/ActionInteractionWkt.java
@@ -30,7 +30,6 @@ import org.apache.causeway.applib.Identifier;
 import org.apache.causeway.applib.annotation.Where;
 import org.apache.causeway.commons.collections.Can;
 import org.apache.causeway.commons.internal.assertions._Assert;
-import org.apache.causeway.commons.internal.base._Lazy;
 import org.apache.causeway.commons.internal.exceptions._Exceptions;
 import 
org.apache.causeway.core.metamodel.interactions.managed.ActionInteraction;
 import 
org.apache.causeway.core.metamodel.interactions.managed.ParameterNegotiationModel;
@@ -136,10 +135,6 @@ extends HasBookmarkedOwnerAbstract<ActionInteraction> {
     @Override
     protected ActionInteraction load() {
 
-        // setup the lazy, don't yet evaluate
-        parameterNegotiationModel =
-                
_Lazy.threadSafe(()->actionInteraction().startParameterNegotiation());
-
         if(associatedWithParameterIfAny!=null) {
             final int paramIndex = 
associatedWithParameterIfAny.getParameterIndex();
             // supports composite-value-types via mixin
@@ -206,18 +201,18 @@ extends HasBookmarkedOwnerAbstract<ActionInteraction> {
         return childModels.stream();
     }
 
-    // -- PARAMETER NEGOTIATION WITH MEMOIZATION (TRANSIENT)
-
-    private transient _Lazy<Optional<ParameterNegotiationModel>> 
parameterNegotiationModel;
+    // -- PARAMETER NEGOTIATION
 
     public final ParameterNegotiationModel parameterNegotiationModel() {
-        _Assert.assertTrue(this.isAttached(), "model is not attached");
-        return parameterNegotiationModel.get()
-                .orElseThrow(()->_Exceptions.noSuchElement(memberId));
+        guardAgainstNotAttached();
+        return parameterNegotiationModel!=null
+                ? parameterNegotiationModel
+                : startParameterNegotiationModel();
     }
 
     public void resetParametersToDefault() {
-        parameterNegotiationModel.clear();
+        // in effect invalidates the currently memoized 
parameterNegotiationModel (if any)
+        this.parameterNegotiationModel = null;
     }
 
     public InlinePromptContext getInlinePromptContext() {
@@ -228,4 +223,29 @@ extends HasBookmarkedOwnerAbstract<ActionInteraction> {
                     : null;
     }
 
+    // -- HELPER
+
+    /**
+     * memoized transiently
+     */
+    private transient ParameterNegotiationModel parameterNegotiationModel;
+    /**
+     * Start and transiently memoize a new {@link ParameterNegotiationModel}.
+     */
+    private ParameterNegotiationModel startParameterNegotiationModel() {
+        return this.parameterNegotiationModel = 
actionInteraction().startParameterNegotiation()
+                .orElseThrow(()->_Exceptions.noSuchElement(memberId));
+    }
+    /**
+     * [CAUSEWAY-3649] safe guard against access to the model while it is not 
attached
+     */
+    private void guardAgainstNotAttached() {
+        if(!this.isAttached()) {
+            // start over
+            this.parameterNegotiationModel = null;
+            getObject();
+        }
+        _Assert.assertTrue(this.isAttached(), ()->"model is not attached");
+    }
+
 }