Use optional

2 files changed, 16 insertions, 19 deletions

diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/processing/ImplicitSummaryFields.java b/config-model/src/main/java/com/yahoo/searchdefinition/processing/ImplicitSummaryFields.java
index ff0a0d07102..e11f7d370c5 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/processing/ImplicitSummaryFields.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/processing/ImplicitSummaryFields.java
@@ -23,7 +23,7 @@ public class ImplicitSummaryFields extends Processor {
     @Override
     public void process(boolean validate, boolean documentsOnly) {
         for (DocumentSummary docsum : schema.getSummariesInThis().values()) {
-            if (docsum.getInherited() != null) continue; // Implicit fields are added to inheriting summaries through their parent
+            if (docsum.inherited().isPresent()) continue; // Implicit fields are added to inheriting summaries through their parent
             addField(docsum, new SummaryField("rankfeatures", DataType.STRING, SummaryTransform.RANKFEATURES), validate);
             addField(docsum, new SummaryField("summaryfeatures", DataType.STRING, SummaryTransform.SUMMARYFEATURES), validate);
         }
diff --git a/config-model/src/main/java/com/yahoo/vespa/documentmodel/DocumentSummary.java b/config-model/src/main/java/com/yahoo/vespa/documentmodel/DocumentSummary.java
index 967e662dc6b..90ab6ad8fa1 100644
--- a/config-model/src/main/java/com/yahoo/vespa/documentmodel/DocumentSummary.java
+++ b/config-model/src/main/java/com/yahoo/vespa/documentmodel/DocumentSummary.java
@@ -8,6 +8,7 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Optional;
 import java.util.logging.Level;
 
 /**
@@ -19,7 +20,7 @@ public class DocumentSummary extends FieldView {
 
     private boolean fromDisk = false;
     private boolean omitSummaryFeatures = false;
-    private String inherited;
+    private Optional<String> inherited = Optional.empty();
 
     private final Schema owner;
 
@@ -57,20 +58,16 @@ public class DocumentSummary extends FieldView {
     public SummaryField getSummaryField(String name) {
         var field = (SummaryField)get(name);
         if (field != null) return field;
-        if (getInherited() == null)  return null;
-        return getInherited().getSummaryField(name);
+        if (inherited().isEmpty()) return null;
+        return inherited().get().getSummaryField(name);
     }
 
     // TODO: This does not handle overriding in child summaries correctly
     public Collection<SummaryField> getSummaryFields() {
         var fields = new ArrayList<SummaryField>(getFields().size());
-        var parent = getInherited();
-        if (parent != null) {
-            fields.addAll(parent.getSummaryFields());
-        }
-        for (var field : getFields()) {
+        inherited().ifPresent(inherited -> fields.addAll(inherited.getSummaryFields()));
+        for (var field : getFields())
             fields.add((SummaryField) field);
-        }
         return fields;
     }
 
@@ -101,12 +98,12 @@ public class DocumentSummary extends FieldView {
 
     /** Sets the parent of this. Both summaries must be present in the same search definition */
     public void setInherited(String inherited) {
-        this.inherited = inherited;
+        this.inherited = Optional.of(inherited);
     }
 
-    /** Returns the parent of this, or null if none is inherited */
-    public DocumentSummary getInherited() {
-        return owner.getSummary(inherited);
+    /** Returns the parent of this, if any */
+    public Optional<DocumentSummary> inherited() {
+        return inherited.map(name -> owner.getSummary(name));
     }
 
     @Override
@@ -115,14 +112,14 @@ public class DocumentSummary extends FieldView {
     }
 
     public void validate(DeployLogger logger) {
-        if (inherited != null) {
-            if ( ! owner.getSummaries().containsKey(inherited)) {
+        if (inherited.isPresent()) {
+            if ( ! owner.getSummaries().containsKey(inherited.get())) {
                 logger.log(Level.WARNING,
-                           this + " inherits " + inherited + " but this" + " is not present in " + owner);
+                           this + " inherits " + inherited.get() + " but this" + " is not present in " + owner);
                 logger.logApplicationPackage(Level.WARNING,
-                                             this + " inherits " + inherited + " but this" + " is not present in " + owner);
+                                             this + " inherits " + inherited.get() + " but this" + " is not present in " + owner);
                 // TODO: When safe, replace the above by
-                // throw new IllegalArgumentException(this + " inherits " + inherited + " but this" +
+                // throw new IllegalArgumentException(this + " inherits " + inherited.get() + " but this" +
                 //                                   " is not present in " + owner);
                 // ... and update SummaryTestCase.testValidationOfInheritedSummary
             }