Bug 570856: [Toolsmiths][AF] Improve messages for command-class constraints

- introduce custom messages for problems in the command class attributes
- includes a second step to distinguish diagnosis of missing class versus
  a class that doesn't implement the expected protocol
- requires generation of the plug-in class for the Papyrus Representation model
- update existing JUnit tests to accommodate new diagnostic messages

Change-Id: I351466b561700fdcda68d23b1385821d4d8fc1a9
Signed-off-by: Christian W. Damus <give.a.damus@gmail.com>

3 files changed, 51 insertions, 11 deletions

diff --git a/plugins/infra/core/org.eclipse.papyrus.infra.core.architecture/plugin.properties b/plugins/infra/core/org.eclipse.papyrus.infra.core.architecture/plugin.properties
index 6055ab0689f..2ab38948aae 100644
--- a/plugins/infra/core/org.eclipse.papyrus.infra.core.architecture/plugin.properties
+++ b/plugins/infra/core/org.eclipse.papyrus.infra.core.architecture/plugin.properties
@@ -14,3 +14,9 @@
 
 pluginName = Architecture Model
 providerName=Eclipse Modeling Project
+
+_UI_creationCommandClassExists_diagnostic = Model creation command of ''{0}'' is not found in the Java classpath.
+_UI_creationCommandClassConforms_diagnostic = Model creation command of ''{0}'' does not implement the {1} interface.
+_UI_genericRequiredInterface_name = required
+_UI_conversionCommandClassExists_diagnostic = Model conversion command of ''{0}'' is not found in the Java classpath.
+_UI_conversionCommandClassConforms_diagnostic = Model conversion command of ''{0}'' does not implement the {1} interface.
diff --git a/plugins/infra/core/org.eclipse.papyrus.infra.core.architecture/src-gen/org/eclipse/papyrus/infra/core/architecture/impl/ArchitectureContextImpl.java b/plugins/infra/core/org.eclipse.papyrus.infra.core.architecture/src-gen/org/eclipse/papyrus/infra/core/architecture/impl/ArchitectureContextImpl.java
index dcfd450eddd..bd2f7121ecd 100644
--- a/plugins/infra/core/org.eclipse.papyrus.infra.core.architecture/src-gen/org/eclipse/papyrus/infra/core/architecture/impl/ArchitectureContextImpl.java
+++ b/plugins/infra/core/org.eclipse.papyrus.infra.core.architecture/src-gen/org/eclipse/papyrus/infra/core/architecture/impl/ArchitectureContextImpl.java
@@ -1,5 +1,5 @@
 /**
-* Copyright (c) 2017, 2021 CEA LIST, Christian W. Damus, and others.
+ * Copyright (c) 2017, 2021 CEA LIST, Christian W. Damus, and others.
  * 
  *  All rights reserved. This program and the accompanying materials
  *  are made available under the terms of the Eclipse Public License 2.0
@@ -10,8 +10,7 @@
  *  
  *  Contributors:
  *  Maged Elaasar - Initial API and implementation
- *  Christian W. Damus - bug, 539694
- *  
+ *  Christian W. Damus - bugs 539694, 570856
  * 
  */
 package org.eclipse.papyrus.infra.core.architecture.impl;
@@ -29,7 +28,6 @@ import org.eclipse.emf.common.util.EList;
 import org.eclipse.emf.ecore.EClass;
 import org.eclipse.emf.ecore.InternalEObject;
 import org.eclipse.emf.ecore.impl.ENotificationImpl;
-import org.eclipse.emf.ecore.plugin.EcorePlugin;
 import org.eclipse.emf.ecore.util.EObjectContainmentWithInverseEList;
 import org.eclipse.emf.ecore.util.EObjectResolvingEList;
 import org.eclipse.emf.ecore.util.EObjectValidator;
@@ -294,13 +292,19 @@ public abstract class ArchitectureContextImpl extends ADElementImpl implements A
 			
 			if (!exists) {
 				if (diagnostics != null) {
+					// Further narrow the problem
+					String problem = ArchitectureCommandUtils.getCommandClassUnconstrained(this, ArchitecturePackage.Literals.ARCHITECTURE_CONTEXT__CREATION_COMMAND_CLASS) == null
+							? "_UI_creationCommandClassExists_diagnostic" : "_UI_creationCommandClassConforms_diagnostic"; //$NON-NLS-1$//$NON-NLS-2$
+					String expectedInterface = ArchitectureCommandUtils.getCommandType( ArchitecturePackage.Literals.ARCHITECTURE_CONTEXT__CREATION_COMMAND_CLASS)
+							.map(Class::getSimpleName).orElse(ArchitecturePlugin.INSTANCE.getString("_UI_genericRequiredInterface_name")); //$NON-NLS-1$
+					
 					diagnostics.add
 						(new BasicDiagnostic
 							(Diagnostic.ERROR,
 							 ArchitectureValidator.DIAGNOSTIC_SOURCE,
 							 ArchitectureValidator.ARCHITECTURE_CONTEXT__CEATION_COMMAND_CLASS_EXISTS,
-							 EcorePlugin.INSTANCE.getString("_UI_GenericInvariant_diagnostic", new Object[] { "ceationCommandClassExists", EObjectValidator.getObjectLabel(this, context) }), //$NON-NLS-1$ //$NON-NLS-2$
-							 new Object [] { this }));
+							 ArchitecturePlugin.INSTANCE.getString(problem, new Object[] { EObjectValidator.getObjectLabel(this, context), expectedInterface }),
+							 new Object [] { this, ArchitecturePackage.Literals.ARCHITECTURE_CONTEXT__CREATION_COMMAND_CLASS }));
 				}
 				return false;
 			}
@@ -322,13 +326,19 @@ public abstract class ArchitectureContextImpl extends ADElementImpl implements A
 			
 			if (!exists) {
 				if (diagnostics != null) {
+					// Further narrow the problem
+					String problem = ArchitectureCommandUtils.getCommandClassUnconstrained(this, ArchitecturePackage.Literals.ARCHITECTURE_CONTEXT__CONVERSION_COMMAND_CLASS) == null
+							? "_UI_conversionCommandClassExists_diagnostic" : "_UI_conversionCommandClassConforms_diagnostic"; //$NON-NLS-1$//$NON-NLS-2$
+					String expectedInterface = ArchitectureCommandUtils.getCommandType( ArchitecturePackage.Literals.ARCHITECTURE_CONTEXT__CONVERSION_COMMAND_CLASS)
+							.map(Class::getSimpleName).orElse(ArchitecturePlugin.INSTANCE.getString("_UI_genericRequiredInterface_name")); //$NON-NLS-1$
+					
 					diagnostics.add
 						(new BasicDiagnostic
 							(Diagnostic.ERROR,
 							 ArchitectureValidator.DIAGNOSTIC_SOURCE,
 							 ArchitectureValidator.ARCHITECTURE_CONTEXT__CONVERSION_COMMAND_CLASS_EXISTS,
-							 EcorePlugin.INSTANCE.getString("_UI_GenericInvariant_diagnostic", new Object[] { "conversionCommandClassExists", EObjectValidator.getObjectLabel(this, context) }), //$NON-NLS-1$ //$NON-NLS-2$
-							 new Object [] { this }));
+							 ArchitecturePlugin.INSTANCE.getString(problem, new Object[] { EObjectValidator.getObjectLabel(this, context), expectedInterface }),
+							 new Object [] { this, ArchitecturePackage.Literals.ARCHITECTURE_CONTEXT__CONVERSION_COMMAND_CLASS }));
 				}
 				return false;
 			}
diff --git a/plugins/infra/core/org.eclipse.papyrus.infra.core.architecture/src/org/eclipse/papyrus/infra/core/architecture/util/ArchitectureCommandUtils.java b/plugins/infra/core/org.eclipse.papyrus.infra.core.architecture/src/org/eclipse/papyrus/infra/core/architecture/util/ArchitectureCommandUtils.java
index 15a58a6caa8..067fc3ae040 100644
--- a/plugins/infra/core/org.eclipse.papyrus.infra.core.architecture/src/org/eclipse/papyrus/infra/core/architecture/util/ArchitectureCommandUtils.java
+++ b/plugins/infra/core/org.eclipse.papyrus.infra.core.architecture/src/org/eclipse/papyrus/infra/core/architecture/util/ArchitectureCommandUtils.java
@@ -92,7 +92,8 @@ public class ArchitectureCommandUtils {
 	}
 
 	/**
-	 * Get the command class referenced by the given feature of an architecture model object.
+	 * Get the command class referenced by the given feature of an architecture model object, if it
+	 * conforms to constraints (if any) declared in the Ecore model.
 	 *
 	 * @param modelObject
 	 *            the architecture model object for which to load a command class
@@ -105,9 +106,17 @@ public class ArchitectureCommandUtils {
 	 *         {@code IType}, depending whether JDT is available
 	 */
 	public static Object getCommandClass(EObject modelObject, EStructuralFeature commandClassFeature) {
+		return getCommandClass(modelObject, commandClassFeature, getCommandType(commandClassFeature));
+	}
+
+	private static Object getCommandClass(EObject modelObject, EStructuralFeature commandClassFeature, Optional<Class<?>> registeredType) {
 		if (commandClassFeature.getEType().getInstanceClass() == Class.class) {
 			// Easy
-			return modelObject.eGet(commandClassFeature);
+			Class<?> result = (Class<?>) modelObject.eGet(commandClassFeature);
+			if (result != null && registeredType.isPresent() && !registeredType.get().isAssignableFrom(result)) {
+				result = null;
+			}
+			return result;
 		}
 
 		String className = Optional.ofNullable(modelObject.eGet(commandClassFeature)).map(String::valueOf).orElse(null);
@@ -116,10 +125,25 @@ public class ArchitectureCommandUtils {
 			return null;
 		}
 
-		Optional<Class<?>> registeredType = getCommandType(commandClassFeature);
 		URI context = EcoreUtil.getURI(modelObject).trimFragment();
 
 		return ClasspathHelper.INSTANCE.findClass(className, context, registeredType.orElse(null));
 	}
 
+	/**
+	 * Get the command class referenced by the given feature of an architecture model object, not considering
+	 * any constraints imposed on it by the Ecore model.
+	 *
+	 * @param modelObject
+	 *            the architecture model object for which to load a command class
+	 * @param commandClassFeature
+	 *            the model feature that names the command class
+	 * @return
+	 *         the referenced class, or {@code null} if the class doesn't exist. The result may be a Java
+	 *         {@link Class} or a JDT {@code IType}, depending whether JDT is available
+	 */
+	public static Object getCommandClassUnconstrained(EObject modelObject, EStructuralFeature commandClassFeature) {
+		return getCommandClass(modelObject, commandClassFeature, Optional.empty());
+	}
+
 }