Decouple correlations from shadows, part one

We plan to support correlation of (partial) focus objects to their
candidate matches. No shadows will be involved.

As a preparation, the CorrelationContext was made abstract, and two
children were created: Shadow and Focus. The latter is not finished.

Work in progress.

model/model-api/src/main/java/com/evolveum/midpoint/model/api/correlation/CorrelationContext.java

@@ -30,28 +30,13 @@
  *
  * Not to be confused with {@link CorrelatorContext} which describes the context of the whole {@link Correlator} lifespan.
  */
-public class CorrelationContext implements DebugDumpable, Cloneable {
-
-    /**
-     * Shadowed resource object to be correlated.
-     */
-    @NotNull private final ShadowType resourceObject;
+public abstract class CorrelationContext implements DebugDumpable, Cloneable {
 
     /**
      * Focus that was created using pre-mappings.
      * May be empty (but not null) e.g. if there are no such mappings.
      */
-    @NotNull private final FocusType preFocus;
-
-    /**
-     * Resource on which the correlated shadow resides.
-     */
-    @NotNull private final ResourceType resource;
-
-    /**
-     * Usually resource object type definition (~ schemaHandling section).
-     */
-    @NotNull private final ResourceObjectDefinition resourceObjectDefinition;
+    @NotNull final FocusType preFocus;
 
     /**
      * System configuration to use during the correlation.
@@ -70,24 +55,14 @@ public class CorrelationContext implements DebugDumpable, Cloneable {
     private AbstractCorrelatorStateType correlatorState;
 
     public CorrelationContext(
-            @NotNull ShadowType resourceObject,
             @NotNull FocusType preFocus,
-            @NotNull ResourceType resource,
-            @NotNull ResourceObjectDefinition objectDefinition,
             @Nullable SystemConfigurationType systemConfiguration,
             @NotNull Task task) {
-        this.resourceObject = resourceObject;
         this.preFocus = preFocus;
-        this.resource = resource;
-        this.resourceObjectDefinition = objectDefinition;
         this.systemConfiguration = systemConfiguration;
         this.task = task;
     }
 
-    public @NotNull ShadowType getResourceObject() {
-        return resourceObject;
-    }
-
     public @NotNull FocusType getPreFocus() {
         return preFocus;
     }
@@ -96,20 +71,8 @@ public CorrelationContext(
         return preFocus.getClass();
     }
 
-    public @Nullable String getArchetypeOid() {
-        // Note that the archetype OID can be specified only on the object type. It is not supported
-        // for legacy synchronization definition. Therefore we may safely access it in the following way:
-        ResourceObjectTypeDefinition typeDefinition = resourceObjectDefinition.getTypeDefinition();
-        return typeDefinition != null ? typeDefinition.getArchetypeOid() : null;
-    }
-
-    public @NotNull ResourceType getResource() {
-        return resource;
-    }
-
-    public @NotNull ResourceObjectDefinition getResourceObjectDefinition() {
-        return resourceObjectDefinition;
-    }
+    /** Returns the archetype for focus objects that the candidate(s) must possess. Null means "no restrictions".  */
+    public abstract @Nullable String getArchetypeOid();
 
     public @Nullable SystemConfigurationType getSystemConfiguration() {
         return systemConfiguration;
@@ -127,27 +90,23 @@ public void setCorrelatorState(AbstractCorrelatorStateType correlatorState) {
         return task;
     }
 
-    @Override
-    public String toString() {
-        return "CorrelationContext("
-                + getFocusType().getSimpleName() + ", "
-                + resourceObjectDefinition.getHumanReadableName() + "@" + resource
-                + ')';
-    }
-
     @Override
     public String debugDump(int indent) {
         StringBuilder sb = DebugUtil.createTitleStringBuilderLn(getClass(), indent);
-        DebugUtil.debugDumpWithLabelLn(sb, "resourceObject", resourceObject, indent + 1);
         DebugUtil.debugDumpWithLabelLn(sb, "preFocus", preFocus, indent + 1);
         DebugUtil.debugDumpWithLabelLn(sb, "focusType", getFocusType(), indent + 1);
-        DebugUtil.debugDumpWithLabelLn(sb, "resource", String.valueOf(resource), indent + 1);
-        DebugUtil.debugDumpWithLabelLn(sb, "resourceObjectDefinition", String.valueOf(resourceObjectDefinition), indent + 1);
+        debugDumpSpecific(sb, indent);
         DebugUtil.debugDumpWithLabelLn(sb, "systemConfiguration", String.valueOf(systemConfiguration), indent + 1);
         DebugUtil.debugDumpWithLabel(sb, "correlatorState", correlatorState, indent + 1);
         return sb.toString();
     }
 
+    void debugDumpSpecific(StringBuilder sb, int indent) {
+        // Nothing to do here. To be overridden by subclasses.
+    }
+
+    public @NotNull abstract Shadow asShadowCtx();
+
     /**
      * A simple shallow clone. Use with care.
      */
@@ -159,4 +118,119 @@ public CorrelationContext clone() {
             throw new SystemException(e);
         }
     }
+
+    /** Returns the object (e.g. shadow or focus) that is being correlated. Currently for logging purposes. */
+    @NotNull public abstract ObjectType getPrimaryCorrelatedObject();
+
+    /** Context for correlating a shadow to a set of matching focuses. */
+    public static class Shadow extends CorrelationContext {
+
+        /**
+         * Shadowed resource object to be correlated.
+         */
+        @NotNull private final ShadowType resourceObject;
+
+        /**
+         * Resource on which the correlated shadow resides.
+         */
+        @NotNull private final ResourceType resource;
+
+        /**
+         * Usually resource object type definition (~ schemaHandling section).
+         */
+        @NotNull private final ResourceObjectDefinition resourceObjectDefinition;
+
+        public Shadow(
+                @NotNull ShadowType resourceObject,
+                @NotNull ResourceType resource,
+                @NotNull ResourceObjectDefinition resourceObjectDefinition,
+                @NotNull FocusType preFocus,
+                @Nullable SystemConfigurationType systemConfiguration,
+                @NotNull Task task) {
+            super(preFocus, systemConfiguration, task);
+            this.resourceObject = resourceObject;
+            this.resource = resource;
+            this.resourceObjectDefinition = resourceObjectDefinition;
+        }
+
+        public @NotNull ShadowType getResourceObject() {
+            return resourceObject;
+        }
+
+        public @NotNull ResourceType getResource() {
+            return resource;
+        }
+
+        public @NotNull ResourceObjectDefinition getResourceObjectDefinition() {
+            return resourceObjectDefinition;
+        }
+
+        public @Nullable String getArchetypeOid() {
+            // Note that the archetype OID can be specified only on the object type. It is not supported
+            // for legacy synchronization definition. Therefore we may safely access it in the following way:
+            ResourceObjectTypeDefinition typeDefinition = resourceObjectDefinition.getTypeDefinition();
+            return typeDefinition != null ? typeDefinition.getArchetypeOid() : null;
+        }
+
+        @Override
+        public @NotNull Shadow asShadowCtx() {
+            return this;
+        }
+
+        @Override
+        public @NotNull ObjectType getPrimaryCorrelatedObject() {
+            return resourceObject;
+        }
+
+        @Override
+        public String toString() {
+            return "CorrelationContext.Shadow("
+                    + getFocusType().getSimpleName() + ", "
+                    + resourceObjectDefinition.getHumanReadableName() + "@" + resource
+                    + ')';
+        }
+
+        @Override
+        void debugDumpSpecific(StringBuilder sb, int indent) {
+            DebugUtil.debugDumpWithLabelLn(sb, "resourceObject", resourceObject, indent + 1);
+            DebugUtil.debugDumpWithLabelLn(sb, "resource", String.valueOf(resource), indent + 1);
+            DebugUtil.debugDumpWithLabelLn(sb, "resourceObjectDefinition", String.valueOf(resourceObjectDefinition), indent + 1);
+        }
+    }
+
+    /**
+     * Context for correlating a focus to a set of matching focuses.
+     *
+     * TODO finish this class
+     */
+    public static class Focus extends CorrelationContext {
+
+        public Focus(
+                @NotNull FocusType preFocus, @Nullable SystemConfigurationType systemConfiguration, @NotNull Task task) {
+            super(preFocus, systemConfiguration, task);
+        }
+
+        @Override
+        public @NotNull Shadow asShadowCtx() {
+            throw new IllegalStateException("Focus context cannot be used as shadow context");
+        }
+
+        @Override
+        public @Nullable String getArchetypeOid() {
+            throw new UnsupportedOperationException(); // TODO implement
+        }
+
+        @Override
+        public @NotNull ObjectType getPrimaryCorrelatedObject() {
+            return preFocus;
+        }
+
+        @Override
+        public String toString() {
+            return "CorrelationContext.Focus("
+                    + getFocusType().getSimpleName() + ", "
+                    + preFocus
+                    + ')';
+        }
+    }
 }

model/model-impl/src/main/java/com/evolveum/midpoint/model/impl/correlation/CorrelationServiceImpl.java

@@ -181,7 +181,7 @@ public boolean checkCandidateOwner(
             CommunicationException, ConfigurationException, ObjectNotFoundException {
         FocusType preFocus = computePreFocus(
                 shadowedResourceObject, resource, synchronizationPolicy, candidateOwner.getClass(), task, result);
-        CompleteContext ctx = new CompleteContext(
+        CompleteContext ctx = CompleteContext.forShadow(
                 shadowedResourceObject,
                 resource,
                 synchronizationPolicy.getObjectTypeDefinition(),
@@ -333,7 +333,8 @@ void resolve(
                                         kind, intent, resource, shadow)));
 
         FocusType preFocus = computePreFocus(shadow, resource, policy, policy.getFocusClass(), task, result);
-        return new CompleteContext(
+
+        return CompleteContext.forShadow(
                 shadow,
                 resource,
                 policy.getObjectTypeDefinition(),
@@ -408,12 +409,11 @@ public ObjectTemplateType determineObjectTemplate(
     }
 
     /** Contains both {@link CorrelatorContext} and {@link CorrelationContext}. Usually we create both of them together. */
-    private static class CompleteContext {
-
-        @NotNull final CorrelatorContext<?> correlatorContext;
-        @NotNull final CorrelationContext correlationContext;
+    private record CompleteContext(
+            @NotNull CorrelatorContext<?> correlatorContext,
+            @NotNull CorrelationContext correlationContext) {
 
-        CompleteContext(
+        static CompleteContext forShadow(
                 @NotNull ShadowType shadow,
                 @NotNull ResourceType resource,
                 @NotNull ResourceObjectDefinition resourceObjectDefinition,
@@ -423,19 +423,20 @@ private static class CompleteContext {
                 @Nullable SystemConfigurationType systemConfiguration,
                 @NotNull Task task)
                 throws SchemaException, ConfigurationException {
-            this.correlatorContext =
+            var correlatorContext =
                     CorrelatorContextCreator.createRootContext(
                             synchronizationPolicy.getCorrelationDefinition(),
                             objectTemplate,
                             systemConfiguration);
-            this.correlationContext =
-                    new CorrelationContext(
+            var correlationContext =
+                    new CorrelationContext.Shadow(
                             shadow,
-                            preFocus,
                             resource,
                             resourceObjectDefinition,
+                            preFocus,
                             systemConfiguration,
                             task);
+            return new CompleteContext(correlatorContext, correlationContext);
         }
     }
 }

model/model-impl/src/main/java/com/evolveum/midpoint/model/impl/correlator/BaseCorrelator.java

@@ -197,10 +197,17 @@ protected abstract double checkCandidateOwnerInternal(
             SecurityViolationException, ObjectNotFoundException;
 
     protected @NotNull String getDefaultContextDescription(@NotNull CorrelationContext correlationContext) {
-        return (typeName + " correlator" +
-                (configurationBean.getName() != null ? " '" + configurationBean.getName() + "'" : ""))
-                + " for " + correlationContext.getResourceObjectDefinition().getHumanReadableName()
-                + " in " + correlationContext.getResource();
+        String prefix =
+                typeName + " correlator" +
+                        (configurationBean.getName() != null ? " '" + configurationBean.getName() + "'" : "");
+        if (correlationContext instanceof CorrelationContext.Shadow shadowCtx) {
+            return prefix
+                    + " for " + shadowCtx.getResourceObjectDefinition().getHumanReadableName()
+                    + " in " + shadowCtx.getResource();
+        } else {
+            // TODO something for the focus-only correlation
+            return prefix;
+        }
     }
 
     protected @NotNull Correlator instantiateChild(

model/model-impl/src/main/java/com/evolveum/midpoint/model/impl/correlator/CorrelatorUtil.java

@@ -42,7 +42,7 @@ public static VariablesMap getVariablesMap(
         VariablesMap variables = ModelImplUtils.getDefaultVariablesMap(
                 focus,
                 resourceObject,
-                correlationContext.getResource(),
+                correlationContext instanceof CorrelationContext.Shadow shadow ? shadow.getResource() : null,
                 correlationContext.getSystemConfiguration());
         variables.put(ExpressionConstants.VAR_CORRELATION_CONTEXT, correlationContext, CorrelationContext.class);
         variables.put(ExpressionConstants.VAR_CORRELATOR_STATE,

model/model-impl/src/main/java/com/evolveum/midpoint/model/impl/correlator/expression/ExpressionCorrelator.java

@@ -44,6 +44,8 @@
 /**
  * A correlator based on expressions that directly provide focal object(s) (or their references) for given resource object.
  * Similar to synchronization sorter, but simpler - it treats only correlation, not the classification part.
+ *
+ * Currently supports only shadow-based correlations.
  */
 class ExpressionCorrelator extends BaseCorrelator<ExpressionCorrelatorType> {
 
@@ -60,7 +62,7 @@ class ExpressionCorrelator extends BaseCorrelator<ExpressionCorrelatorType> {
             throws SchemaException, ExpressionEvaluationException, CommunicationException, SecurityViolationException,
             ConfigurationException, ObjectNotFoundException {
 
-        return new Correlation<>(correlationContext)
+        return new Correlation<>(correlationContext.asShadowCtx())
                 .execute(result);
     }
 
@@ -82,14 +84,14 @@ private class Correlation<F extends FocusType> {
         /** TODO: determine from the resource */
         @Nullable private final ExpressionProfile expressionProfile = MiscSchemaUtil.getExpressionProfile();
 
-        Correlation(@NotNull CorrelationContext correlationContext) {
+        Correlation(@NotNull CorrelationContext.Shadow correlationContext) {
             this.resourceObject = correlationContext.getResourceObject();
             this.correlationContext = correlationContext;
             this.task = correlationContext.getTask();
             this.contextDescription = getDefaultContextDescription(correlationContext);
         }
 
-        public CorrelationResult execute(OperationResult result)
+        CorrelationResult execute(OperationResult result)
                 throws SchemaException, ExpressionEvaluationException, CommunicationException, SecurityViolationException,
                 ConfigurationException, ObjectNotFoundException {
             ObjectSet<F> candidateOwners = findCandidatesUsingExpressions(result);
@@ -158,8 +160,7 @@ private void addCandidateOwner(ObjectSet<F> allCandidates, PrismValue candidateV
                 //noinspection unchecked
                 candidateOwner = ((PrismObjectValue<F>) candidateValue).asObjectable();
                 checkOidPresent(candidateOwner.getOid(), candidateValue);
-            } else if (candidateValue instanceof PrismReferenceValue) {
-                PrismReferenceValue candidateOwnerRef = (PrismReferenceValue) candidateValue;
+            } else if (candidateValue instanceof PrismReferenceValue candidateOwnerRef) {
                 String oid = candidateOwnerRef.getOid();
                 checkOidPresent(oid, candidateValue);
                 if (allCandidates.containsOid(oid)) {