Add NOT operator to VectorStore portable filter expressions

spring-ai-core/src/main/java/org/springframework/ai/vectorstore/filter/Filter.java

@@ -114,7 +114,7 @@ public record Value(Object value) implements Operand {
 	 */
 	public enum ExpressionType {
 
-		AND, OR, EQ, NE, GT, GTE, LT, LTE, IN, NIN
+		AND, OR, EQ, NE, GT, GTE, LT, LTE, IN, NIN, NOT
 
 	}
 
@@ -131,6 +131,9 @@ public enum ExpressionType {
 	 * be another {@link Expression}.
 	 */
 	public record Expression(ExpressionType type, Operand left, Operand right) implements Operand {
+		public Expression(ExpressionType type, Operand operand) {
+			this(type, operand, null);
+		}
 	}
 
 	/**

spring-ai-core/src/main/java/org/springframework/ai/vectorstore/filter/FilterExpressionBuilder.java

@@ -122,4 +122,8 @@ public Op group(Op content) {
 		return new Op(new Filter.Group(content.build()));
 	}
 
+	public Op not(Op content) {
+		return new Op(new Filter.Expression(ExpressionType.NOT, content.expression, null));
+	}
+
 }

spring-ai-core/src/main/java/org/springframework/ai/vectorstore/filter/FilterExpressionTextParser.java

@@ -35,6 +35,7 @@
 import org.springframework.ai.vectorstore.filter.antlr4.FiltersBaseVisitor;
 import org.springframework.ai.vectorstore.filter.antlr4.FiltersLexer;
 import org.springframework.ai.vectorstore.filter.antlr4.FiltersParser;
+import org.springframework.ai.vectorstore.filter.antlr4.FiltersParser.NotExpressionContext;
 import org.springframework.core.NestedExceptionUtils;
 import org.springframework.util.Assert;
 
@@ -263,6 +264,11 @@ public Filter.Operand visitGroupExpression(FiltersParser.GroupExpressionContext
 			return new Filter.Group(castToExpression(this.visit(ctx.booleanExpression())));
 		}
 
+		@Override
+		public Filter.Operand visitNotExpression(NotExpressionContext ctx) {
+			return new Filter.Expression(Filter.ExpressionType.NOT, this.visit(ctx.booleanExpression()), null);
+		}
+
 		public Filter.Expression castToExpression(Filter.Operand expression) {
 			if (expression instanceof Filter.Group group) {
 				// Remove the top-level grouping.

spring-ai-core/src/main/java/org/springframework/ai/vectorstore/filter/FilterHelper.java

@@ -0,0 +1,205 @@
+/*
+ * Copyright 2023-2023 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.ai.vectorstore.filter;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+import org.springframework.ai.vectorstore.filter.Filter.Expression;
+import org.springframework.ai.vectorstore.filter.Filter.ExpressionType;
+import org.springframework.ai.vectorstore.filter.Filter.Operand;
+import org.springframework.ai.vectorstore.filter.converter.FilterExpressionConverter;
+import org.springframework.util.Assert;
+
+/**
+ * Helper class providing various boolean transformation.
+ *
+ * @author Christian Tzolov
+ */
+public class FilterHelper {
+
+	private FilterHelper() {
+	}
+
+	private final static Map<ExpressionType, ExpressionType> TYPE_NEGATION_MAP = Map.of(ExpressionType.AND,
+			ExpressionType.OR, ExpressionType.OR, ExpressionType.AND, ExpressionType.EQ, ExpressionType.NE,
+			ExpressionType.NE, ExpressionType.EQ, ExpressionType.GT, ExpressionType.LTE, ExpressionType.GTE,
+			ExpressionType.LT, ExpressionType.LT, ExpressionType.GTE, ExpressionType.LTE, ExpressionType.GT,
+			ExpressionType.IN, ExpressionType.NIN, ExpressionType.NIN, ExpressionType.IN);
+
+	/**
+	 * Transforms the input expression into a semantically equivalent one with negation
+	 * operators propagated thought the expression tree by following the negation rules:
+	 *
+	 * <pre>
+	 * 	NOT(NOT(a)) = a
+	 *
+	 * 	NOT(a AND b) = NOT(a) OR NOT(b)
+	 * 	NOT(a OR b) = NOT(a) AND NOT(b)
+	 *
+	 * 	NOT(a EQ b) = a NE b
+	 * 	NOT(a NE b) = a EQ b
+	 *
+	 * 	NOT(a GT b) = a LTE b
+	 * 	NOT(a GTE b) = a LT b
+	 *
+	 * 	NOT(a LT b) = a GTE b
+	 * 	NOT(a LTE b) = a GT b
+	 *
+	 * 	NOT(a IN [...]) = a NIN [...]
+	 * 	NOT(a NIN [...]) = a IN [...]
+	 * </pre>
+	 * @param operand Filter expression to negate.
+	 * @return Returns an negation of the input expression.
+	 */
+	public static Filter.Operand negate(Filter.Operand operand) {
+
+		if (operand instanceof Filter.Group group) {
+			Operand inEx = negate(group.content());
+			if (inEx instanceof Filter.Group inEx2) {
+				inEx = inEx2.content();
+			}
+			return new Filter.Group((Expression) inEx);
+		}
+		else if (operand instanceof Filter.Expression exp) {
+			switch (exp.type()) {
+				case NOT: // NOT(NOT(a)) = a
+					return negate(exp.left());
+				case AND: // NOT(a AND b) = NOT(a) OR NOT(b)
+				case OR: // NOT(a OR b) = NOT(a) AND NOT(b)
+					return new Filter.Expression(TYPE_NEGATION_MAP.get(exp.type()), negate(exp.left()),
+							negate(exp.right()));
+				case EQ: // NOT(e EQ b) = e NE b
+				case NE: // NOT(e NE b) = e EQ b
+				case GT: // NOT(e GT b) = e LTE b
+				case GTE: // NOT(e GTE b) = e LT b
+				case LT: // NOT(e LT b) = e GTE b
+				case LTE: // NOT(e LTE b) = e GT b
+					return new Filter.Expression(TYPE_NEGATION_MAP.get(exp.type()), exp.left(), exp.right());
+				case IN: // NOT(e IN [...]) = e NIN [...]
+				case NIN: // NOT(e NIN [...]) = e IN [...]
+					return new Filter.Expression(TYPE_NEGATION_MAP.get(exp.type()), exp.left(), exp.right());
+				default:
+					throw new IllegalArgumentException("Unknown expression type: " + exp.type());
+			}
+		}
+		else {
+			throw new IllegalArgumentException("Can not negate operand of type: " + operand.getClass());
+		}
+	}
+
+	/**
+	 * Expands the IN into a semantically equivalent boolean expressions of ORs of EQs.
+	 * Useful for providers that don't provide native IN support.
+	 *
+	 * For example the <pre>
+	 * foo IN ["bar1", "bar2", "bar3"]
+	 * </pre>
+	 *
+	 * expression is equivalent to
+	 *
+	 * <pre>
+	 * {@code foo == "bar1" || foo == "bar2" || foo == "bar3" (e.g. OR(foo EQ "bar1" OR(foo EQ "bar2" OR(foo EQ "bar3")))}
+	 * </pre>
+	 * @param exp input IN expression.
+	 * @param context Output native expression.
+	 * @param filterExpressionConverter {@link FilterExpressionConverter} used to compose
+	 * the OR and EQ expanded expressions.
+	 */
+	public static void expandIn(Expression exp, StringBuilder context,
+			FilterExpressionConverter filterExpressionConverter) {
+		Assert.isTrue(exp.type() == ExpressionType.IN, "Expected IN expressions but was: " + exp.type());
+		expandInNinExpressions(ExpressionType.OR, ExpressionType.EQ, exp, context, filterExpressionConverter);
+	}
+
+	/**
+	 *
+	 * Expands the NIN (e.g. NOT IN) into a semantically equivalent boolean expressions of
+	 * ANDs of NEs. Useful for providers that don't provide native NIN support.<br/>
+	 *
+	 * For example the
+	 *
+	 * <pre>
+	 * foo NIN ["bar1", "bar2", "bar3"] (or foo NOT IN ["bar1", "bar2", "bar3"])
+	 * </pre>
+	 *
+	 * express is equivalent to
+	 *
+	 * <pre>
+	 * {@code foo != "bar1" && foo != "bar2" && foo != "bar3" (e.g. AND(foo NE "bar1" AND( foo NE "bar2" OR(foo NE "bar3"))) )}
+	 * </pre>
+	 * @param exp input NIN expression.
+	 * @param context Output native expression.
+	 * @param filterExpressionConverter {@link FilterExpressionConverter} used to compose
+	 * the AND and NE expanded expressions.
+	 */
+	public static void expandNin(Expression exp, StringBuilder context,
+			FilterExpressionConverter filterExpressionConverter) {
+		Assert.isTrue(exp.type() == ExpressionType.NIN, "Expected NIN expressions but was: " + exp.type());
+		expandInNinExpressions(ExpressionType.AND, ExpressionType.NE, exp, context, filterExpressionConverter);
+	}
+
+	private static void expandInNinExpressions(Filter.ExpressionType outerExpressionType,
+			Filter.ExpressionType innerExpressionType, Expression exp, StringBuilder context,
+			FilterExpressionConverter expressionConverter) {
+		if (exp.right() instanceof Filter.Value value) {
+			if (value.value() instanceof List list) {
+				// 1. foo IN ["bar1", "bar2", "bar3"] is equivalent to foo == "bar1" ||
+				// foo == "bar2" || foo == "bar3"
+				// or equivalent to OR(foo == "bar1" OR( foo == "bar2" OR(foo == "bar3")))
+				// 2. foo IN ["bar1", "bar2", "bar3"] is equivalent to foo != "bar1" &&
+				// foo != "bar2" && foo != "bar3"
+				// or equivalent to AND(foo != "bar1" AND( foo != "bar2" OR(foo !=
+				// "bar3")))
+				List<Filter.Expression> eqExprs = new ArrayList<>();
+				for (Object o : list) {
+					eqExprs.add(new Filter.Expression(innerExpressionType, exp.left(), new Filter.Value(o)));
+				}
+				context.append(expressionConverter.convertExpression(aggregate(outerExpressionType, eqExprs)));
+			}
+			else {
+				// 1. foo IN ["bar"] is equivalent to foo == "BAR"
+				// 2. foo NIN ["bar"] is equivalent to foo != "BAR"
+				context.append(expressionConverter
+					.convertExpression(new Filter.Expression(innerExpressionType, exp.left(), exp.right())));
+			}
+		}
+		else {
+			throw new IllegalStateException(
+					"Filter IN right expression should be of Filter.Value type but was " + exp.right().getClass());
+		}
+	}
+
+	/**
+	 * Recursively aggregates a list of expression into a binary tree with 'aggregateType'
+	 * join nodes.
+	 * @param aggregateType type all tree splits.
+	 * @param expressions list of expressions to aggregate.
+	 * @return Returns a binary tree expression.
+	 */
+	private static Filter.Expression aggregate(Filter.ExpressionType aggregateType,
+			List<Filter.Expression> expressions) {
+
+		if (expressions.size() == 1) {
+			return expressions.get(0);
+		}
+		return new Filter.Expression(aggregateType, expressions.get(0),
+				aggregate(aggregateType, expressions.subList(1, expressions.size())));
+	}
+
+}

spring-ai-core/src/main/java/org/springframework/ai/vectorstore/filter/antlr4/Filters.interp

@@ -66,4 +66,4 @@ constant
 
 
 atn:
-[4, 1, 26, 87, 2, 0, 7, 0, 2, 1, 7, 1, 2, 2, 7, 2, 2, 3, 7, 3, 2, 4, 7, 4, 2, 5, 7, 5, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 30, 8, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 38, 8, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 5, 1, 46, 8, 1, 10, 1, 12, 1, 49, 9, 1, 1, 2, 1, 2, 1, 2, 1, 2, 5, 2, 55, 8, 2, 10, 2, 12, 2, 58, 9, 2, 1, 2, 1, 2, 1, 3, 1, 3, 1, 4, 1, 4, 1, 4, 1, 4, 1, 4, 3, 4, 69, 8, 4, 1, 5, 3, 5, 72, 8, 5, 1, 5, 1, 5, 3, 5, 76, 8, 5, 1, 5, 1, 5, 4, 5, 80, 8, 5, 11, 5, 12, 5, 81, 1, 5, 3, 5, 85, 8, 5, 1, 5, 0, 1, 2, 6, 0, 2, 4, 6, 8, 10, 0, 2, 2, 0, 8, 8, 11, 15, 1, 0, 9, 10, 95, 0, 12, 1, 0, 0, 0, 2, 37, 1, 0, 0, 0, 4, 50, 1, 0, 0, 0, 6, 61, 1, 0, 0, 0, 8, 68, 1, 0, 0, 0, 10, 84, 1, 0, 0, 0, 12, 13, 5, 1, 0, 0, 13, 14, 3, 2, 1, 0, 14, 15, 5, 0, 0, 1, 15, 1, 1, 0, 0, 0, 16, 17, 6, 1, -1, 0, 17, 18, 3, 8, 4, 0, 18, 19, 3, 6, 3, 0, 19, 20, 3, 10, 5, 0, 20, 38, 1, 0, 0, 0, 21, 22, 3, 8, 4, 0, 22, 23, 5, 18, 0, 0, 23, 24, 3, 4, 2, 0, 24, 38, 1, 0, 0, 0, 25, 29, 3, 8, 4, 0, 26, 27, 5, 20, 0, 0, 27, 30, 5, 18, 0, 0, 28, 30, 5, 19, 0, 0, 29, 26, 1, 0, 0, 0, 29, 28, 1, 0, 0, 0, 30, 31, 1, 0, 0, 0, 31, 32, 3, 4, 2, 0, 32, 38, 1, 0, 0, 0, 33, 34, 5, 6, 0, 0, 34, 35, 3, 2, 1, 0, 35, 36, 5, 7, 0, 0, 36, 38, 1, 0, 0, 0, 37, 16, 1, 0, 0, 0, 37, 21, 1, 0, 0, 0, 37, 25, 1, 0, 0, 0, 37, 33, 1, 0, 0, 0, 38, 47, 1, 0, 0, 0, 39, 40, 10, 3, 0, 0, 40, 41, 5, 16, 0, 0, 41, 46, 3, 2, 1, 4, 42, 43, 10, 2, 0, 0, 43, 44, 5, 17, 0, 0, 44, 46, 3, 2, 1, 3, 45, 39, 1, 0, 0, 0, 45, 42, 1, 0, 0, 0, 46, 49, 1, 0, 0, 0, 47, 45, 1, 0, 0, 0, 47, 48, 1, 0, 0, 0, 48, 3, 1, 0, 0, 0, 49, 47, 1, 0, 0, 0, 50, 51, 5, 4, 0, 0, 51, 56, 3, 10, 5, 0, 52, 53, 5, 3, 0, 0, 53, 55, 3, 10, 5, 0, 54, 52, 1, 0, 0, 0, 55, 58, 1, 0, 0, 0, 56, 54, 1, 0, 0, 0, 56, 57, 1, 0, 0, 0, 57, 59, 1, 0, 0, 0, 58, 56, 1, 0, 0, 0, 59, 60, 5, 5, 0, 0, 60, 5, 1, 0, 0, 0, 61, 62, 7, 0, 0, 0, 62, 7, 1, 0, 0, 0, 63, 64, 5, 25, 0, 0, 64, 65, 5, 2, 0, 0, 65, 69, 5, 25, 0, 0, 66, 69, 5, 25, 0, 0, 67, 69, 5, 22, 0, 0, 68, 63, 1, 0, 0, 0, 68, 66, 1, 0, 0, 0, 68, 67, 1, 0, 0, 0, 69, 9, 1, 0, 0, 0, 70, 72, 7, 1, 0, 0, 71, 70, 1, 0, 0, 0, 71, 72, 1, 0, 0, 0, 72, 73, 1, 0, 0, 0, 73, 85, 5, 23, 0, 0, 74, 76, 7, 1, 0, 0, 75, 74, 1, 0, 0, 0, 75, 76, 1, 0, 0, 0, 76, 77, 1, 0, 0, 0, 77, 85, 5, 24, 0, 0, 78, 80, 5, 22, 0, 0, 79, 78, 1, 0, 0, 0, 80, 81, 1, 0, 0, 0, 81, 79, 1, 0, 0, 0, 81, 82, 1, 0, 0, 0, 82, 85, 1, 0, 0, 0, 83, 85, 5, 21, 0, 0, 84, 71, 1, 0, 0, 0, 84, 75, 1, 0, 0, 0, 84, 79, 1, 0, 0, 0, 84, 83, 1, 0, 0, 0, 85, 11, 1, 0, 0, 0, 10, 29, 37, 45, 47, 56, 68, 71, 75, 81, 84]
+[4, 1, 26, 89, 2, 0, 7, 0, 2, 1, 7, 1, 2, 2, 7, 2, 2, 3, 7, 3, 2, 4, 7, 4, 2, 5, 7, 5, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 30, 8, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 40, 8, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 5, 1, 48, 8, 1, 10, 1, 12, 1, 51, 9, 1, 1, 2, 1, 2, 1, 2, 1, 2, 5, 2, 57, 8, 2, 10, 2, 12, 2, 60, 9, 2, 1, 2, 1, 2, 1, 3, 1, 3, 1, 4, 1, 4, 1, 4, 1, 4, 1, 4, 3, 4, 71, 8, 4, 1, 5, 3, 5, 74, 8, 5, 1, 5, 1, 5, 3, 5, 78, 8, 5, 1, 5, 1, 5, 4, 5, 82, 8, 5, 11, 5, 12, 5, 83, 1, 5, 3, 5, 87, 8, 5, 1, 5, 0, 1, 2, 6, 0, 2, 4, 6, 8, 10, 0, 2, 2, 0, 8, 8, 11, 15, 1, 0, 9, 10, 98, 0, 12, 1, 0, 0, 0, 2, 39, 1, 0, 0, 0, 4, 52, 1, 0, 0, 0, 6, 63, 1, 0, 0, 0, 8, 70, 1, 0, 0, 0, 10, 86, 1, 0, 0, 0, 12, 13, 5, 1, 0, 0, 13, 14, 3, 2, 1, 0, 14, 15, 5, 0, 0, 1, 15, 1, 1, 0, 0, 0, 16, 17, 6, 1, -1, 0, 17, 18, 3, 8, 4, 0, 18, 19, 3, 6, 3, 0, 19, 20, 3, 10, 5, 0, 20, 40, 1, 0, 0, 0, 21, 22, 3, 8, 4, 0, 22, 23, 5, 18, 0, 0, 23, 24, 3, 4, 2, 0, 24, 40, 1, 0, 0, 0, 25, 29, 3, 8, 4, 0, 26, 27, 5, 20, 0, 0, 27, 30, 5, 18, 0, 0, 28, 30, 5, 19, 0, 0, 29, 26, 1, 0, 0, 0, 29, 28, 1, 0, 0, 0, 30, 31, 1, 0, 0, 0, 31, 32, 3, 4, 2, 0, 32, 40, 1, 0, 0, 0, 33, 34, 5, 6, 0, 0, 34, 35, 3, 2, 1, 0, 35, 36, 5, 7, 0, 0, 36, 40, 1, 0, 0, 0, 37, 38, 5, 20, 0, 0, 38, 40, 3, 2, 1, 1, 39, 16, 1, 0, 0, 0, 39, 21, 1, 0, 0, 0, 39, 25, 1, 0, 0, 0, 39, 33, 1, 0, 0, 0, 39, 37, 1, 0, 0, 0, 40, 49, 1, 0, 0, 0, 41, 42, 10, 4, 0, 0, 42, 43, 5, 16, 0, 0, 43, 48, 3, 2, 1, 5, 44, 45, 10, 3, 0, 0, 45, 46, 5, 17, 0, 0, 46, 48, 3, 2, 1, 4, 47, 41, 1, 0, 0, 0, 47, 44, 1, 0, 0, 0, 48, 51, 1, 0, 0, 0, 49, 47, 1, 0, 0, 0, 49, 50, 1, 0, 0, 0, 50, 3, 1, 0, 0, 0, 51, 49, 1, 0, 0, 0, 52, 53, 5, 4, 0, 0, 53, 58, 3, 10, 5, 0, 54, 55, 5, 3, 0, 0, 55, 57, 3, 10, 5, 0, 56, 54, 1, 0, 0, 0, 57, 60, 1, 0, 0, 0, 58, 56, 1, 0, 0, 0, 58, 59, 1, 0, 0, 0, 59, 61, 1, 0, 0, 0, 60, 58, 1, 0, 0, 0, 61, 62, 5, 5, 0, 0, 62, 5, 1, 0, 0, 0, 63, 64, 7, 0, 0, 0, 64, 7, 1, 0, 0, 0, 65, 66, 5, 25, 0, 0, 66, 67, 5, 2, 0, 0, 67, 71, 5, 25, 0, 0, 68, 71, 5, 25, 0, 0, 69, 71, 5, 22, 0, 0, 70, 65, 1, 0, 0, 0, 70, 68, 1, 0, 0, 0, 70, 69, 1, 0, 0, 0, 71, 9, 1, 0, 0, 0, 72, 74, 7, 1, 0, 0, 73, 72, 1, 0, 0, 0, 73, 74, 1, 0, 0, 0, 74, 75, 1, 0, 0, 0, 75, 87, 5, 23, 0, 0, 76, 78, 7, 1, 0, 0, 77, 76, 1, 0, 0, 0, 77, 78, 1, 0, 0, 0, 78, 79, 1, 0, 0, 0, 79, 87, 5, 24, 0, 0, 80, 82, 5, 22, 0, 0, 81, 80, 1, 0, 0, 0, 82, 83, 1, 0, 0, 0, 83, 81, 1, 0, 0, 0, 83, 84, 1, 0, 0, 0, 84, 87, 1, 0, 0, 0, 85, 87, 5, 21, 0, 0, 86, 73, 1, 0, 0, 0, 86, 77, 1, 0, 0, 0, 86, 81, 1, 0, 0, 0, 86, 85, 1, 0, 0, 0, 87, 11, 1, 0, 0, 0, 10, 29, 39, 47, 49, 58, 70, 73, 77, 83, 86]

spring-ai-core/src/main/java/org/springframework/ai/vectorstore/filter/antlr4/FiltersBaseListener.java

@@ -121,6 +121,28 @@ public void enterInExpression(FiltersParser.InExpressionContext ctx) {
 	public void exitInExpression(FiltersParser.InExpressionContext ctx) {
 	}
 
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>
+	 * The default implementation does nothing.
+	 * </p>
+	 */
+	@Override
+	public void enterNotExpression(FiltersParser.NotExpressionContext ctx) {
+	}
+
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>
+	 * The default implementation does nothing.
+	 * </p>
+	 */
+	@Override
+	public void exitNotExpression(FiltersParser.NotExpressionContext ctx) {
+	}
+
 	/**
 	 * {@inheritDoc}
 	 *

spring-ai-core/src/main/java/org/springframework/ai/vectorstore/filter/antlr4/FiltersBaseVisitor.java

@@ -86,6 +86,19 @@ public T visitInExpression(FiltersParser.InExpressionContext ctx) {
 		return visitChildren(ctx);
 	}
 
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>
+	 * The default implementation returns the result of calling {@link #visitChildren} on
+	 * {@code ctx}.
+	 * </p>
+	 */
+	@Override
+	public T visitNotExpression(FiltersParser.NotExpressionContext ctx) {
+		return visitChildren(ctx);
+	}
+
 	/**
 	 * {@inheritDoc}
 	 *

spring-ai-core/src/main/java/org/springframework/ai/vectorstore/filter/antlr4/FiltersListener.java

@@ -83,6 +83,20 @@ public interface FiltersListener extends ParseTreeListener {
 	 */
 	void exitInExpression(FiltersParser.InExpressionContext ctx);
 
+	/**
+	 * Enter a parse tree produced by the {@code NotExpression} labeled alternative in
+	 * {@link FiltersParser#booleanExpression}.
+	 * @param ctx the parse tree
+	 */
+	void enterNotExpression(FiltersParser.NotExpressionContext ctx);
+
+	/**
+	 * Exit a parse tree produced by the {@code NotExpression} labeled alternative in
+	 * {@link FiltersParser#booleanExpression}.
+	 * @param ctx the parse tree
+	 */
+	void exitNotExpression(FiltersParser.NotExpressionContext ctx);
+
 	/**
 	 * Enter a parse tree produced by the {@code CompareExpression} labeled alternative in
 	 * {@link FiltersParser#booleanExpression}.