Add DatabaseClient bind variant for list of parameters

Prior to this commit, the `DatabaseClient` interface would allow batch
operations for binding parameters by their names and values. Positional
parameters did not have such equivalent.

This commit adds a new `bindValues(List<?>)` method variant for adding
multiple positional arguments in a single call and avoiding allocation
overhead when the parameters count is large.

Closes gh-33274

Author: bclozel

framework-docs/modules/ROOT/pages/data-access/r2dbc.adoc

@@ -364,6 +364,28 @@ Or you may pass in a parameter object with bean properties or record components:
 			.bindProperties(new Person("joe", "Joe", 34);
 ----
 
+Alternatively, you can use positional parameters for binding values to statements.
+Indices are zero based.
+
+[source,java]
+----
+    db.sql("INSERT INTO person (id, name, age) VALUES(:id, :name, :age)")
+	    	.bind(0, "joe")
+	    	.bind(1, "Joe")
+			.bind(2, 34);
+----
+
+In case your application is binding to many parameters, the same can be achieved with a single call:
+
+[source,java]
+----
+    List<?> values = List.of("joe", "Joe", 34);
+    db.sql("INSERT INTO person (id, name, age) VALUES(:id, :name, :age)")
+	    	.bindValues(values);
+----
+
+
+
 .R2DBC Native Bind Markers
 ****
 R2DBC uses database-native bind markers that depend on the actual database vendor.

spring-r2dbc/src/main/java/org/springframework/r2dbc/core/DatabaseClient.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -16,6 +16,7 @@
 
 package org.springframework.r2dbc.core;
 
+import java.util.List;
 import java.util.Map;
 import java.util.function.BiFunction;
 import java.util.function.Consumer;
@@ -56,6 +57,7 @@
  *
  * @author Mark Paluch
  * @author Juergen Hoeller
+ * @author Brian Clozel
  * @since 5.3
  */
 public interface DatabaseClient extends ConnectionAccessor {
@@ -191,6 +193,18 @@ interface GenericExecuteSpec {
 		 */
 		GenericExecuteSpec bindNull(String name, Class<?> type);
 
+		/**
+		 * Bind the parameter values from the given source list,
+		 * registering each as a positional parameter using their order
+		 * in the given list as their index.
+		 * @param source the source list of parameters, with their order
+		 * as position and each value either a scalar value
+		 * or a {@link io.r2dbc.spi.Parameter}
+		 * @since 6.2
+		 * @see #bind(int, Object)
+		 */
+		GenericExecuteSpec bindValues(List<?> source);
+
 		/**
 		 * Bind the parameter values from the given source map,
 		 * registering each as a parameter with the map key as name.

spring-r2dbc/src/main/java/org/springframework/r2dbc/core/DefaultDatabaseClient.java

@@ -24,6 +24,7 @@
 import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
+import java.util.ListIterator;
 import java.util.Map;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.function.BiFunction;
@@ -308,6 +309,18 @@ public DefaultGenericExecuteSpec bindNull(String name, Class<?> type) {
 			return new DefaultGenericExecuteSpec(this.byIndex, byName, this.sqlSupplier, this.filterFunction);
 		}
 
+		@Override
+		public GenericExecuteSpec bindValues(List<?> source) {
+			assertNotPreparedOperation();
+			Assert.notNull(source, "Source list must not be null");
+			Map<Integer, Parameter> byIndex = new LinkedHashMap<>(this.byIndex);
+			ListIterator<?> listIterator = source.listIterator();
+			while (listIterator.hasNext()) {
+				byIndex.put(listIterator.nextIndex(), resolveParameter(listIterator.next()));
+			}
+			return new DefaultGenericExecuteSpec(byIndex, this.byName, this.sqlSupplier, this.filterFunction);
+		}
+
 		@Override
 		public GenericExecuteSpec bindValues(Map<String, ?> source) {
 			assertNotPreparedOperation();

spring-r2dbc/src/test/java/org/springframework/r2dbc/core/AbstractDatabaseClientIntegrationTests.java

@@ -16,6 +16,7 @@
 
 package org.springframework.r2dbc.core;
 
+import java.util.List;
 import java.util.Map;
 
 import io.r2dbc.spi.ConnectionFactory;
@@ -96,6 +97,25 @@ void executeInsert() {
 				.verifyComplete();
 	}
 
+	@Test
+	void executeInsertWithList() {
+		DatabaseClient databaseClient = DatabaseClient.create(connectionFactory);
+
+		databaseClient.sql("INSERT INTO legoset (id, name, manual) VALUES(:id, :name, :manual)")
+				.bindValues(List.of(42055, Parameters.in("SCHAUFELRADBAGGER"), Parameters.in(Integer.class)))
+				.fetch().rowsUpdated()
+				.as(StepVerifier::create)
+				.expectNext(1L)
+				.verifyComplete();
+
+		databaseClient.sql("SELECT id FROM legoset")
+				.mapValue(Integer.class)
+				.first()
+				.as(StepVerifier::create)
+				.assertNext(actual -> assertThat(actual).isEqualTo(42055))
+				.verifyComplete();
+	}
+
 	@Test
 	void executeInsertWithMap() {
 		DatabaseClient databaseClient = DatabaseClient.create(connectionFactory);