ST6RI-897 Moved non-gen code for FlowUsage.isAbstract to adapter.

Author: seidewitz

org.omg.sysml.xpect.tests/src/org/omg/sysml/xpect/tests/validation/invalid/Relationship_invalid_relatedElement1.sysml.xt

@@ -49,6 +49,7 @@ package 'Streaming Example' {
 			"Cannot identify flow end (use dot notation)" at "C::myIn"
 			"Must be an accessible feature (use dot notation for nesting)" at "B::myOut"
 			"Must be an accessible feature (use dot notation for nesting)" at "C::myIn"
+			"Must have at least two related elements" at "flow XXX from B::myOut to C::myIn;"
 		    --- */
 		flow XXX from B::myOut to C::myIn;	
 	} 

org.omg.sysml/src/org/omg/sysml/adapter/FlowUsageAdapter.java

@@ -1,6 +1,6 @@
 /*******************************************************************************
  * SysML 2 Pilot Implementation
- * Copyright (c) 2021-2025 Model Driven Solutions, Inc.
+ * Copyright (c) 2021-2026 Model Driven Solutions, Inc.
  *    
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Lesser General Public License as published by
@@ -99,9 +99,22 @@ protected String getDefaultSupertype() {
 				getDefaultSupertype("base");
 	}
 
+	/**
+	 * @satisfies validateConnectorRelatedFeatures
+	 * (For a FlowUsage that is a message.)
+	 */
+	protected void makeMessageAbstract() {
+		super.postProcess();
+		FlowUsage target = getTarget();
+		if (UsageUtil.isMessageConnection(target) && target.getRelatedFeature().size() < 2) {
+			target.setIsAbstract(true);
+		}
+	}
+	
 	@Override
 	public void doTransform() {
 		ConnectorUtil.transformConnectorEndsOf(getTarget());
+		makeMessageAbstract();
 		super.doTransform();
 	}
 

org.omg.sysml/syntax-gen/org/omg/sysml/lang/sysml/impl/FlowUsageImpl.java

@@ -1,6 +1,6 @@
 /*******************************************************************************
  * SysML 2 Pilot Implementation
- * Copyright (c) 2022, 2024 Model Driven Solutions, Inc.
+ * Copyright (c) 2022, 2024, 2026 Model Driven Solutions, Inc.
  *    
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Lesser General Public License as published by
@@ -637,21 +637,6 @@ public boolean isSubactionUsage() {
 		}
 	}
 
-	// Additional overrides
-	
-	/**
-	 * @generated NOT
-	 */
-	@Override
-	public boolean isAbstract() {
-		if (getRelatedFeature().size() < 2) {
-			isAbstract = true;
-		}
-		return super.isAbstract();
-	}
-	
-	//
-
 	/**
 	 * <!-- begin-user-doc -->
 	 * <!-- end-user-doc -->