Bugfixing and improving MongoDB's QueryParser

client-java/controller/src/main/java/org/evomaster/client/java/controller/mongo/MongoHeuristicsCalculator.java

@@ -20,7 +20,7 @@ public class MongoHeuristicsCalculator {
     private final TaintHandler taintHandler;
 
     public MongoHeuristicsCalculator() {
-       this(null);
+        this(null);
     }
 
     public MongoHeuristicsCalculator(TaintHandler taintHandler) {
@@ -35,63 +35,65 @@ public MongoHeuristicsCalculator(TaintHandler taintHandler) {
      * @return a branch distance, where 0 means that the document would make the QUERY resolve as true
      */
     public double computeExpression(Object query, Object doc) {
+
         QueryOperation operation = getOperation(query);
-        return calculateDistance(operation, doc);
+        return computeHeuristic(operation, doc);
     }
 
     private QueryOperation getOperation(Object query) {
         return new QueryParser().parse(query);
     }
 
-    private double calculateDistance(QueryOperation operation, Object doc) {
-        if (operation instanceof EqualsOperation<?>)
+    private double computeHeuristic(QueryOperation operation, Object doc) {
+        if (operation instanceof EqualsOperation<?>) {
             return calculateDistanceForEquals((EqualsOperation<?>) operation, doc);
-        if (operation instanceof NotEqualsOperation<?>)
+        } else if (operation instanceof NotEqualsOperation<?>) {
             return calculateDistanceForNotEquals((NotEqualsOperation<?>) operation, doc);
-        if (operation instanceof GreaterThanOperation<?>)
+        } else if (operation instanceof GreaterThanOperation<?>) {
             return calculateDistanceForGreaterThan((GreaterThanOperation<?>) operation, doc);
-        if (operation instanceof GreaterThanEqualsOperation<?>)
+        } else if (operation instanceof GreaterThanEqualsOperation<?>) {
             return calculateDistanceForGreaterEqualsThan((GreaterThanEqualsOperation<?>) operation, doc);
-        if (operation instanceof LessThanOperation<?>)
+        } else if (operation instanceof LessThanOperation<?>) {
             return calculateDistanceForLessThan((LessThanOperation<?>) operation, doc);
-        if (operation instanceof LessThanEqualsOperation<?>)
+        } else if (operation instanceof LessThanEqualsOperation<?>) {
             return calculateDistanceForLessEqualsThan((LessThanEqualsOperation<?>) operation, doc);
-        if (operation instanceof AndOperation)
+        } else if (operation instanceof AndOperation) {
             return calculateDistanceForAnd((AndOperation) operation, doc);
-        if (operation instanceof OrOperation)
+        } else if (operation instanceof OrOperation) {
             return calculateDistanceForOr((OrOperation) operation, doc);
-        if (operation instanceof NorOperation)
+        } else if (operation instanceof NorOperation) {
             return calculateDistanceForNor((NorOperation) operation, doc);
-        if (operation instanceof InOperation<?>)
+        } else if (operation instanceof InOperation<?>) {
             return calculateDistanceForIn((InOperation<?>) operation, doc);
-        if (operation instanceof NotInOperation<?>)
+        } else if (operation instanceof NotInOperation<?>) {
             return calculateDistanceForNotIn((NotInOperation<?>) operation, doc);
-        if (operation instanceof AllOperation<?>)
+        } else if (operation instanceof AllOperation<?>) {
             return calculateDistanceForAll((AllOperation<?>) operation, doc);
-        if (operation instanceof InvertedAllOperation<?>)
+        } else if (operation instanceof InvertedAllOperation<?>) {
             return calculateDistanceForInvertedAll((InvertedAllOperation<?>) operation, doc);
-        if (operation instanceof SizeOperation)
+        } else if (operation instanceof SizeOperation) {
             return calculateDistanceForSize((SizeOperation) operation, doc);
-        if (operation instanceof InvertedSizeOperation)
+        } else if (operation instanceof InvertedSizeOperation) {
             return calculateDistanceForInvertedSize((InvertedSizeOperation) operation, doc);
-        if (operation instanceof ElemMatchOperation)
+        } else if (operation instanceof ElemMatchOperation) {
             return calculateDistanceForElemMatch((ElemMatchOperation) operation, doc);
-        if (operation instanceof ExistsOperation)
+        } else if (operation instanceof ExistsOperation) {
             return calculateDistanceForExists((ExistsOperation) operation, doc);
-        if (operation instanceof ModOperation)
+        } else if (operation instanceof ModOperation) {
             return calculateDistanceForMod((ModOperation) operation, doc);
-        if (operation instanceof InvertedModOperation)
+        } else if (operation instanceof InvertedModOperation) {
             return calculateDistanceForInvertedMod((InvertedModOperation) operation, doc);
-        if (operation instanceof NotOperation)
+        } else if (operation instanceof NotOperation) {
             return calculateDistanceForNot((NotOperation) operation, doc);
-        if (operation instanceof TypeOperation)
+        } else if (operation instanceof TypeOperation) {
             return calculateDistanceForType((TypeOperation) operation, doc);
-        if (operation instanceof InvertedTypeOperation)
+        } else if (operation instanceof InvertedTypeOperation) {
             return calculateDistanceForInvertedType((InvertedTypeOperation) operation, doc);
-        if (operation instanceof NearSphereOperation)
+        } else if (operation instanceof NearSphereOperation) {
             return calculateDistanceForNearSphere((NearSphereOperation) operation, doc);
-
-        return Double.MAX_VALUE;
+        } else {
+            return Double.MAX_VALUE;
+        }
     }
 
     private double calculateDistanceForEquals(EqualsOperation<?> operation, Object doc) {
@@ -134,7 +136,7 @@ private double calculateDistanceForComparisonOperation(ComparisonOperation<?> op
 
     private double calculateDistanceForOr(OrOperation operation, Object doc) {
         return operation.getConditions().stream()
-                .mapToDouble(condition -> calculateDistance(condition, doc))
+                .mapToDouble(condition -> computeHeuristic(condition, doc))
                 .min()
                 .getAsDouble();
     }
@@ -143,7 +145,7 @@ private double calculateDistanceForAnd(AndOperation operation, Object doc) {
         return operation.getConditions()
                 .stream()
                 .mapToDouble(condition ->
-                        TruthnessUtils.normalizeValue(calculateDistance(condition, doc)))
+                        TruthnessUtils.normalizeValue(computeHeuristic(condition, doc)))
                 .sum();
     }
 
@@ -233,7 +235,7 @@ private double calculateDistanceForElemMatch(ElemMatchOperation operation, Objec
                     .mapToDouble(elem -> {
                         Object newDoc = newDocument(doc);
                         appendToDocument(newDoc, operation.getFieldName(), elem);
-                        return calculateDistance(operation.getCondition(), newDoc);
+                        return computeHeuristic(operation.getCondition(), newDoc);
                     })
                     .min()
                     .getAsDouble();
@@ -289,14 +291,14 @@ private double calculateDistanceForNot(NotOperation operation, Object doc) {
         QueryOperation condition = operation.getCondition();
         QueryOperation invertedOperation = invertOperation(condition);
 
-        return calculateDistance(invertedOperation, doc);
+        return computeHeuristic(invertedOperation, doc);
     }
 
     private double calculateDistanceForNor(NorOperation operation, Object doc) {
         return operation.getConditions()
                 .stream()
                 .mapToDouble(condition ->
-                        TruthnessUtils.normalizeValue(calculateDistance(invertOperation(condition), doc)))
+                        TruthnessUtils.normalizeValue(computeHeuristic(invertOperation(condition), doc)))
                 .sum();
     }
 
@@ -332,7 +334,7 @@ private double calculateDistanceForNearSphere(NearSphereOperation operation, Obj
           type key is case-sensitive.
           (https://datatracker.ietf.org/doc/html/rfc7946#section-1.4) for more details.
          */
-        if (isDocument(actualPoint) && getValue(actualPoint, "type").equals("Point") && getValue(actualPoint, "coordinates") instanceof List<?>) {
+        if (isBsonDocument(actualPoint) && getValue(actualPoint, "type").equals("Point") && getValue(actualPoint, "coordinates") instanceof List<?>) {
 
             List<?> coordinates = (List<?>) getValue(actualPoint, "coordinates");
             x2 = Math.toRadians((Double) coordinates.get(0));
@@ -465,8 +467,8 @@ private double compareValues(Object val1, Object val2) {
 
         if (val1 instanceof String && val2 instanceof String) {
 
-            if(taintHandler!=null){
-                taintHandler.handleTaintForStringEquals((String)val1,(String)val2, false);
+            if (taintHandler != null) {
+                taintHandler.handleTaintForStringEquals((String) val1, (String) val2, false);
             }
 
             return (double) DistanceHelper.getLeftAlignmentDistance((String) val1, (String) val2);
@@ -477,15 +479,15 @@ private double compareValues(Object val1, Object val2) {
         }
 
         if (val1 instanceof String && isObjectId(val2)) {
-            if(taintHandler!=null){
-                taintHandler.handleTaintForStringEquals((String)val1,val2.toString(),false);
+            if (taintHandler != null) {
+                taintHandler.handleTaintForStringEquals((String) val1, val2.toString(), false);
             }
             return (double) DistanceHelper.getLeftAlignmentDistance((String) val1, val2.toString());
         }
 
         if (val2 instanceof String && isObjectId(val1)) {
-            if(taintHandler!=null){
-                taintHandler.handleTaintForStringEquals(val1.toString(),val2.toString(),false);
+            if (taintHandler != null) {
+                taintHandler.handleTaintForStringEquals(val1.toString(), val2.toString(), false);
             }
             return (double) DistanceHelper.getLeftAlignmentDistance(val1.toString(), (String) val2);
         }

client-java/controller/src/main/java/org/evomaster/client/java/controller/mongo/QueryParser.java

@@ -6,6 +6,7 @@
 import java.util.Arrays;
 import java.util.List;
 import java.util.Objects;
+import java.util.stream.Collectors;
 
 /**
  * Determines to which operation a query correspond.
@@ -35,11 +36,16 @@ public class QueryParser {
             new ImplicitSelector()
     );
 
-    public QueryOperation parse(Object query) {
-        return selectors.stream()
-                .map(selector -> selector.getOperation(query))
+    public QueryOperation parse(Object bsonDocument) {
+        List<QueryOperation> results = selectors.stream()
+                .map(selector -> selector.getOperation(bsonDocument))
                 .filter(Objects::nonNull)
-                .findFirst()
-                .orElse(null);
+                .collect(Collectors.toList());
+
+        if (results.size() != 1) {
+            return null;
+        }
+
+        return results.get(0);
     }
-}
+}

client-java/controller/src/main/java/org/evomaster/client/java/controller/mongo/selectors/AllSelector.java

@@ -3,21 +3,35 @@
 import org.evomaster.client.java.controller.mongo.operations.*;
 
 import java.util.List;
+import java.util.Objects;
 
 /**
+ * Represents a selector for the MongoDB `$all` operator.
  * { field: { $all: [ value1 , value2 ... ] } }
+ *
+ * <p>
+ * This operator matches arrays that contain all elements specified in the query.
+ * The selector checks if the query value is a list and, if so, creates an
+ * {@link AllOperation} object corresponding to the field and the list of values.
  */
 public class AllSelector extends SingleConditionQuerySelector {
+
+    public static final String ALL_OPERATOR = "$all";
+
     @Override
     protected QueryOperation parseValue(String fieldName, Object value) {
+        Objects.requireNonNull(fieldName);
+        Objects.requireNonNull(value);
+
         if (value instanceof List<?>) {
             return new AllOperation<>(fieldName, (List<?>) value);
+        } else {
+            return null;
         }
-        return null;
     }
 
     @Override
     protected String operator() {
-        return "$all";
+        return ALL_OPERATOR;
     }
-}
+}

client-java/controller/src/main/java/org/evomaster/client/java/controller/mongo/selectors/AndSelector.java

@@ -5,21 +5,24 @@
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 
 /**
+ *  Represents a selector for the MongoDB `$and` operator.
  * { $and: [ { expression1 }, { expression2 } , ... , { expressionN } ] }
  */
 public class AndSelector extends MultiConditionQuerySelector {
 
+    public static final String AND_OPERATOR = "$and";
+
     @Override
-    protected QueryOperation parseConditions(List<?> value) {
-        ArrayList<QueryOperation> conditions = new ArrayList<>();
-        value.forEach(condition -> conditions.add(new QueryParser().parse(condition)));
-        return conditions.isEmpty()? null : new AndOperation(conditions);
+    protected QueryOperation composeConditions(List<QueryOperation> conditions) {
+        Objects.requireNonNull(conditions);
+        return conditions.isEmpty() ? null : new AndOperation(conditions);
     }
 
     @Override
     protected String operator() {
-        return "$and";
+        return AND_OPERATOR;
     }
-}
+}

client-java/controller/src/main/java/org/evomaster/client/java/controller/mongo/selectors/ElemMatchSelector.java

@@ -3,22 +3,31 @@
 import org.evomaster.client.java.controller.mongo.operations.*;
 import org.evomaster.client.java.controller.mongo.QueryParser;
 
-import static org.evomaster.client.java.controller.mongo.utils.BsonHelper.isDocument;
+import java.util.Objects;
+
+import static org.evomaster.client.java.controller.mongo.utils.BsonHelper.isBsonDocument;
 /**
  * { field: { $elemMatch: { query1, query2, ... } } }
  */
 public class ElemMatchSelector extends SingleConditionQuerySelector {
+
+    public static final String ELEM_MATCH_OPERATOR = "$elemMatch";
+
     @Override
     protected QueryOperation parseValue(String fieldName, Object value) {
-        if (isDocument(value)) {
+        Objects.requireNonNull(fieldName);
+        Objects.requireNonNull(value);
+
+        if (isBsonDocument(value)) {
             QueryOperation condition = new QueryParser().parse(value);
             return new ElemMatchOperation(fieldName, condition);
+        } else {
+            return null;
         }
-        return null;
     }
 
     @Override
     protected String operator() {
-        return "$elemMatch";
+        return ELEM_MATCH_OPERATOR;
     }
-}
+}

client-java/controller/src/main/java/org/evomaster/client/java/controller/mongo/selectors/EqualsSelector.java

@@ -3,18 +3,30 @@
 import org.evomaster.client.java.controller.mongo.operations.EqualsOperation;
 import org.evomaster.client.java.controller.mongo.operations.QueryOperation;
 
+import java.util.Objects;
+
 /**
  * { field: { $eq: value } }
  */
 public class EqualsSelector extends SingleConditionQuerySelector {
 
+    public static final String EQUALS_OPERATOR = "$eq";
+
+    /**
+     * Parses the provided field name and value into a QueryOperation representing an equality condition.
+     *
+     * @param fieldName the name of the field involved in the condition; must not be null
+     * @param value the value to match against the field; null is a valid value
+     * @return an instance of EqualsOperation representing the equality condition for the given field and value
+     */
     @Override
     protected QueryOperation parseValue(String fieldName, Object value) {
+        Objects.requireNonNull(fieldName);
         return new EqualsOperation<>(fieldName, value);
     }
 
     @Override
     protected String operator() {
-        return "$eq";
+        return EQUALS_OPERATOR;
     }
-}
+}

client-java/controller/src/main/java/org/evomaster/client/java/controller/mongo/selectors/ExistsSelector.java

@@ -2,18 +2,28 @@
 
 import org.evomaster.client.java.controller.mongo.operations.*;
 
+import java.util.Objects;
+
 /**
  * { field: { $exists: boolean } }
  */
 public class ExistsSelector extends SingleConditionQuerySelector {
+
+    public static final String EXISTS_OPERATOR = "$exists";
+
     @Override
     protected QueryOperation parseValue(String fieldName, Object value) {
-        if (value instanceof Boolean) return new ExistsOperation(fieldName, (Boolean) value);
-        return null;
+        Objects.requireNonNull(fieldName);
+
+        if (value!=null && value instanceof Boolean) {
+            return new ExistsOperation(fieldName, (Boolean) value);
+        } else {
+            return null;
+        }
     }
 
     @Override
     protected String operator() {
-        return "$exists";
+        return EXISTS_OPERATOR;
     }
-}
+}