Merge pull request #5332 from FlorentinD/improve-optional-handling

Make Optional expectations clear

Author: Mats-SX

algo/src/main/java/org/neo4j/gds/paths/delta/DeltaStepping.java

@@ -353,9 +353,8 @@ private static Stream<PathResult> pathResults(
         long sourceNode,
         int concurrency
     ) {
-        assert tentativeDistances.predecessors().isPresent();
         var distances = tentativeDistances.distances();
-        var predecessors = tentativeDistances.predecessors().get();
+        var predecessors = tentativeDistances.predecessors().orElseThrow();
 
         var pathIndex = new AtomicLong(0L);
 

algo/src/main/java/org/neo4j/gds/similarity/nodesim/NodeSimilarityResult.java

@@ -32,10 +32,10 @@ public interface NodeSimilarityResult {
     Optional<SimilarityGraphResult> maybeGraphResult();
 
     default Stream<SimilarityResult> streamResult() {
-        return maybeStreamResult().get();
+        return maybeStreamResult().orElseThrow();
     }
 
     default SimilarityGraphResult graphResult() {
-        return maybeGraphResult().get();
+        return maybeGraphResult().orElseThrow();
     }
 }

core-test-utils/src/main/java/org/neo4j/gds/core/PortFinder.java

@@ -75,7 +75,7 @@ public boolean supportsParameter(ParameterContext parameterContext, ExtensionCon
     @Override
     public Object resolveParameter(ParameterContext parameterContext, ExtensionContext extensionContext)
     throws ParameterResolutionException {
-        return freePortFromStore(extensionContext, parameterContext.findAnnotation(FreePort.class).get());
+        return freePortFromStore(extensionContext, parameterContext.findAnnotation(FreePort.class).orElseThrow());
     }
 
     @Override

core/src/main/java/org/neo4j/gds/core/huge/UnionGraph.java

@@ -92,7 +92,7 @@ public GraphSchema schema() {
             .stream()
             .map(Graph::schema)
             .reduce(GraphSchema::union)
-            .get();
+            .orElseThrow(() -> new IllegalArgumentException("no graphs"));
     }
 
     @Override

core/src/main/java/org/neo4j/gds/core/loading/CSRGraphStoreUtil.java

@@ -134,7 +134,7 @@ private static Map<RelationshipType, RelationshipPropertyStore> constructRelatio
                 .values()
                 .stream()
                 .findFirst()
-                .get();
+                .orElseThrow();
 
             String propertyKey = relationshipProperty.get();
             relationshipProperties = singletonMap(
@@ -145,7 +145,7 @@ private static Map<RelationshipType, RelationshipPropertyStore> constructRelatio
                         propertyKey,
                         NumberType.FLOATING_POINT,
                         relationshipPropertySchema.state(),
-                        relationships.properties().get(),
+                        relationships.properties().orElseThrow(),
                         relationshipPropertySchema.defaultValue().isUserDefined()
                             ? relationshipPropertySchema.defaultValue()
                             : ValueTypes.fromNumberType(NumberType.FLOATING_POINT).fallbackValue(),

core/src/main/java/org/neo4j/gds/core/loading/ScanningNodesImporter.java

@@ -77,7 +77,7 @@ public static ScanningNodesImporter scanningNodesImporter(
 
         LabelInformation.Builder labelInformationBuilder;
         if (graphProjectConfig.nodeProjections().allProjections().size() == 1) {
-            var singleLabel = graphProjectConfig.nodeProjections().projections().keySet().stream().findFirst().get();
+            var singleLabel = graphProjectConfig.nodeProjections().projections().keySet().iterator().next();
             labelInformationBuilder = LabelInformation.single(singleLabel);
         } else {
             labelInformationBuilder = LabelInformation.builder(expectedCapacity, labelTokenNodeLabelMapping);

pipeline/src/main/java/org/neo4j/gds/ml/pipeline/TrainingStatistics.java

@@ -133,7 +133,7 @@ public double getBestTrialScore() {
             .stream()
             .map(stats -> stats.validationStats().get(evaluationMetric()).avg())
             .max(evaluationMetric().comparator())
-            .get();
+            .orElseThrow(() -> new IllegalStateException("Empty validation stats."));
     }
 
     public TrainerConfig bestParameters() {

pregel-proc-generator/src/main/java/org/neo4j/gds/beta/pregel/PregelValidation.java

@@ -198,12 +198,9 @@ private boolean configHasFactoryMethod(Element pregelElement) {
     }
 
     private TypeMirror config(Element pregelElement) {
-        var maybeInterface = pregelComputation(pregelElement);
-        return maybeInterface.get()
-            .getTypeArguments()
-            .stream()
-            .findFirst()
-            .get();
+        return pregelComputation(pregelElement)
+            .map(declaredType -> declaredType.getTypeArguments().get(0))
+            .orElseThrow(() -> new IllegalStateException("Could not find a pregel computation"));
     }
 
     @ValueClass

pregel/src/main/java/org/neo4j/gds/beta/pregel/NodeValue.java

@@ -63,8 +63,8 @@ static NodeValue of(PregelSchema schema, long nodeCount, int concurrency) {
             ));
 
         if (properties.size() == 1) {
-            var element = schema.elements().stream().findFirst().get();
-            var property = properties.values().stream().findFirst().get();
+            var element = schema.elements().iterator().next();
+            var property = properties.values().iterator().next();
             return new SingleNodeValue(schema, element, property);
         }
 

string-formatting/src/main/java/org/neo4j/gds/utils/StringJoining.java

@@ -71,7 +71,7 @@ public static String joinVerbose(Collection<String> alternatives) {
         }
         return joinVerbose(List.of(
             join(alternatives.stream().limit(alternatives.size() - 1), ", "),
-            alternatives.stream().skip(alternatives.size() - 1).findFirst().get()
+            alternatives.stream().skip(alternatives.size() - 1).findFirst().orElseThrow(() -> new IllegalStateException("No alternatives found."))
         ));
     }
 }