Specify generic type nullness in spring-jdbc

See gh-34140

spring-jdbc/src/main/java/org/springframework/jdbc/core/BeanPropertyRowMapper.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2024 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -261,7 +261,7 @@ public class BeanPropertyRowMapper<T> implements RowMapper<T> {
 	 * @param propertyName the property name (as used by property descriptors)
 	 * @since 5.3.9
 	 */
-	protected void suppressProperty(String propertyName) {
+	protected void suppressProperty(@Nullable String propertyName) {
 		if (this.mappedProperties != null) {
 			this.mappedProperties.remove(lowerCaseName(propertyName));
 			this.mappedProperties.remove(underscoreName(propertyName));
@@ -296,7 +296,10 @@ public class BeanPropertyRowMapper<T> implements RowMapper<T> {
 	 * @since 4.2
 	 * @see #underscoreName
 	 */
-	protected String lowerCaseName(String name) {
+	protected String lowerCaseName(@Nullable String name) {
+		if (!StringUtils.hasLength(name)) {
+			return "";
+		}
 		return name.toLowerCase(Locale.US);
 	}
 
@@ -308,7 +311,7 @@ public class BeanPropertyRowMapper<T> implements RowMapper<T> {
 	 * @since 4.2
 	 * @see JdbcUtils#convertPropertyNameToUnderscoreName
 	 */
-	protected String underscoreName(String name) {
+	protected String underscoreName(@Nullable String name) {
 		return JdbcUtils.convertPropertyNameToUnderscoreName(name);
 	}
 

spring-jdbc/src/main/java/org/springframework/jdbc/core/DataClassRowMapper.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -64,7 +64,7 @@ public class DataClassRowMapper<T> extends BeanPropertyRowMapper<T> {
 
 	private @Nullable Constructor<T> mappedConstructor;
 
-	private String @Nullable [] constructorParameterNames;
+	private @Nullable String @Nullable [] constructorParameterNames;
 
 	private TypeDescriptor @Nullable [] constructorParameterTypes;
 
@@ -108,7 +108,7 @@ public class DataClassRowMapper<T> extends BeanPropertyRowMapper<T> {
 	protected T constructMappedInstance(ResultSet rs, TypeConverter tc) throws SQLException {
 		Assert.state(this.mappedConstructor != null, "Mapped constructor was not initialized");
 
-		Object[] args;
+		@Nullable Object[] args;
 		if (this.constructorParameterNames != null && this.constructorParameterTypes != null) {
 			args = new Object[this.constructorParameterNames.length];
 			for (int i = 0; i < args.length; i++) {

spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementCreatorFactory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -154,7 +154,7 @@ public class PreparedStatementCreatorFactory {
 	 * Return a new PreparedStatementSetter for the given parameters.
 	 * @param params the parameter array (may be {@code null})
 	 */
-	public PreparedStatementSetter newPreparedStatementSetter(Object @Nullable [] params) {
+	public PreparedStatementSetter newPreparedStatementSetter(@Nullable Object @Nullable [] params) {
 		return new PreparedStatementCreatorImpl(params != null ? Arrays.asList(params) : Collections.emptyList());
 	}
 
@@ -162,7 +162,7 @@ public class PreparedStatementCreatorFactory {
 	 * Return a new PreparedStatementCreator for the given parameters.
 	 * @param params list of parameters (may be {@code null})
 	 */
-	public PreparedStatementCreator newPreparedStatementCreator(@Nullable List<?> params) {
+	public PreparedStatementCreator newPreparedStatementCreator(@Nullable List<? extends @Nullable Object> params) {
 		return new PreparedStatementCreatorImpl(params != null ? params : Collections.emptyList());
 	}
 
@@ -170,7 +170,7 @@ public class PreparedStatementCreatorFactory {
 	 * Return a new PreparedStatementCreator for the given parameters.
 	 * @param params the parameter array (may be {@code null})
 	 */
-	public PreparedStatementCreator newPreparedStatementCreator(Object @Nullable [] params) {
+	public PreparedStatementCreator newPreparedStatementCreator(@Nullable Object @Nullable [] params) {
 		return new PreparedStatementCreatorImpl(params != null ? Arrays.asList(params) : Collections.emptyList());
 	}
 
@@ -180,7 +180,7 @@ public class PreparedStatementCreatorFactory {
 	 * the factory's, for example because of named parameter expanding)
 	 * @param params the parameter array (may be {@code null})
 	 */
-	public PreparedStatementCreator newPreparedStatementCreator(String sqlToUse, Object @Nullable [] params) {
+	public PreparedStatementCreator newPreparedStatementCreator(String sqlToUse, @Nullable Object @Nullable [] params) {
 		return new PreparedStatementCreatorImpl(
 				sqlToUse, (params != null ? Arrays.asList(params) : Collections.emptyList()));
 	}
@@ -208,7 +208,7 @@ public class PreparedStatementCreatorFactory {
 				Set<String> names = new HashSet<>();
 				for (int i = 0; i < parameters.size(); i++) {
 					Object param = parameters.get(i);
-					if (param instanceof SqlParameterValue sqlParameterValue) {
+					if (param instanceof SqlParameterValue sqlParameterValue && sqlParameterValue.getName() != null) {
 						names.add(sqlParameterValue.getName());
 					}
 					else {

spring-jdbc/src/main/java/org/springframework/jdbc/core/SimplePropertyRowMapper.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -28,6 +28,8 @@ import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.BeanUtils;
 import org.springframework.core.MethodParameter;
 import org.springframework.core.convert.ConversionService;
@@ -82,7 +84,7 @@ public class SimplePropertyRowMapper<T> implements RowMapper<T> {
 
 	private final Constructor<T> mappedConstructor;
 
-	private final String[] constructorParameterNames;
+	private final @Nullable String[] constructorParameterNames;
 
 	private final TypeDescriptor[] constructorParameterTypes;
 
@@ -122,7 +124,7 @@ public class SimplePropertyRowMapper<T> implements RowMapper<T> {
 
 	@Override
 	public T mapRow(ResultSet rs, int rowNumber) throws SQLException {
-		Object[] args = new Object[this.constructorParameterNames.length];
+		@Nullable Object[] args = new Object[this.constructorParameterNames.length];
 		Set<Integer> usedIndex = new HashSet<>();
 		for (int i = 0; i < args.length; i++) {
 			String name = this.constructorParameterNames[i];

spring-jdbc/src/main/java/org/springframework/jdbc/core/namedparam/NamedParameterJdbcTemplate.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -370,7 +370,7 @@ public class NamedParameterJdbcTemplate implements NamedParameterJdbcOperations
 				new BatchPreparedStatementSetter() {
 					@Override
 					public void setValues(PreparedStatement ps, int i) throws SQLException {
-						Object[] values = NamedParameterUtils.buildValueArray(parsedSql, batchArgs[i], null);
+						@Nullable Object[] values = NamedParameterUtils.buildValueArray(parsedSql, batchArgs[i], null);
 						pscf.newPreparedStatementSetter(values).setValues(ps);
 					}
 					@Override
@@ -407,12 +407,12 @@ public class NamedParameterJdbcTemplate implements NamedParameterJdbcOperations
 		else {
 			pscf.setReturnGeneratedKeys(true);
 		}
-		Object[] params = NamedParameterUtils.buildValueArray(parsedSql, paramSource, null);
+		@Nullable Object[] params = NamedParameterUtils.buildValueArray(parsedSql, paramSource, null);
 		PreparedStatementCreator psc = pscf.newPreparedStatementCreator(params);
 		return getJdbcOperations().batchUpdate(psc, new BatchPreparedStatementSetter() {
 			@Override
 			public void setValues(PreparedStatement ps, int i) throws SQLException {
-				Object[] values = NamedParameterUtils.buildValueArray(parsedSql, batchArgs[i], null);
+				@Nullable Object[] values = NamedParameterUtils.buildValueArray(parsedSql, batchArgs[i], null);
 				pscf.newPreparedStatementSetter(values).setValues(ps);
 			}
 
@@ -460,7 +460,7 @@ public class NamedParameterJdbcTemplate implements NamedParameterJdbcOperations
 		if (customizer != null) {
 			customizer.accept(pscf);
 		}
-		Object[] params = NamedParameterUtils.buildValueArray(parsedSql, paramSource, null);
+		@Nullable Object[] params = NamedParameterUtils.buildValueArray(parsedSql, paramSource, null);
 		return pscf.newPreparedStatementCreator(params);
 	}
 

spring-jdbc/src/main/java/org/springframework/jdbc/core/namedparam/NamedParameterUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2024 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -348,10 +348,10 @@ public abstract class NamedParameterUtils {
 	 * be built into the value array in the form of SqlParameterValue objects.
 	 * @return the array of values
 	 */
-	public static Object[] buildValueArray(
+	public static @Nullable Object[] buildValueArray(
 			ParsedSql parsedSql, SqlParameterSource paramSource, @Nullable List<SqlParameter> declaredParams) {
 
-		Object[] paramArray = new Object[parsedSql.getTotalParameterCount()];
+		@Nullable Object[] paramArray = new Object[parsedSql.getTotalParameterCount()];
 		if (parsedSql.getNamedParameterCount() > 0 && parsedSql.getUnnamedParameterCount() > 0) {
 			throw new InvalidDataAccessApiUsageException(
 					"Not allowed to mix named and traditional ? placeholders. You have " +
@@ -497,7 +497,7 @@ public abstract class NamedParameterUtils {
 	 * @param paramMap the Map of parameters
 	 * @return the array of values
 	 */
-	public static Object[] buildValueArray(String sql, Map<String, ?> paramMap) {
+	public static @Nullable Object[] buildValueArray(String sql, Map<String, ?> paramMap) {
 		ParsedSql parsedSql = parseSqlStatement(sql);
 		return buildValueArray(parsedSql, new MapSqlParameterSource(paramMap), null);
 	}

spring-jdbc/src/main/java/org/springframework/jdbc/object/GenericSqlQuery.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -70,7 +70,7 @@ public class GenericSqlQuery<T> extends SqlQuery<T> {
 
 	@Override
 	@SuppressWarnings("unchecked")
-	protected RowMapper<T> newRowMapper(Object @Nullable [] parameters, @Nullable Map<?, ?> context) {
+	protected RowMapper<T> newRowMapper(@Nullable Object @Nullable [] parameters, @Nullable Map<?, ?> context) {
 		if (this.rowMapper != null) {
 			return this.rowMapper;
 		}

spring-jdbc/src/main/java/org/springframework/jdbc/object/MappingSqlQuery.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -63,7 +63,7 @@ public abstract class MappingSqlQuery<T> extends MappingSqlQueryWithParameters<T
 	 * @see #mapRow(ResultSet, int)
 	 */
 	@Override
-	protected final @Nullable T mapRow(ResultSet rs, int rowNum, Object @Nullable [] parameters, @Nullable Map<?, ?> context)
+	protected final @Nullable T mapRow(ResultSet rs, int rowNum, @Nullable Object @Nullable [] parameters, @Nullable Map<?, ?> context)
 			throws SQLException {
 
 		return mapRow(rs, rowNum);

spring-jdbc/src/main/java/org/springframework/jdbc/object/MappingSqlQueryWithParameters.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -74,7 +74,7 @@ public abstract class MappingSqlQueryWithParameters<T> extends SqlQuery<T> {
 	 * implementation of the mapRow() method.
 	 */
 	@Override
-	protected RowMapper<T> newRowMapper(Object @Nullable [] parameters, @Nullable Map<?, ?> context) {
+	protected RowMapper<T> newRowMapper(@Nullable Object @Nullable [] parameters, @Nullable Map<?, ?> context) {
 		return new RowMapperImpl(parameters, context);
 	}
 
@@ -93,7 +93,7 @@ public abstract class MappingSqlQueryWithParameters<T> extends SqlQuery<T> {
 	 * Subclasses can simply not catch SQLExceptions, relying on the
 	 * framework to clean up.
 	 */
-	protected abstract @Nullable T mapRow(ResultSet rs, int rowNum, Object @Nullable [] parameters, @Nullable Map<?, ?> context)
+	protected abstract @Nullable T mapRow(ResultSet rs, int rowNum, @Nullable Object @Nullable [] parameters, @Nullable Map<?, ?> context)
 			throws SQLException;
 
 
@@ -103,14 +103,14 @@ public abstract class MappingSqlQueryWithParameters<T> extends SqlQuery<T> {
 	 */
 	protected class RowMapperImpl implements RowMapper<T> {
 
-		private final Object @Nullable [] params;
+		private final @Nullable Object @Nullable [] params;
 
 		private final @Nullable Map<?, ?> context;
 
 		/**
 		 * Use an array results. More efficient if we know how many results to expect.
 		 */
-		public RowMapperImpl(Object @Nullable [] parameters, @Nullable Map<?, ?> context) {
+		public RowMapperImpl(@Nullable Object @Nullable [] parameters, @Nullable Map<?, ?> context) {
 			this.params = parameters;
 			this.context = context;
 		}

spring-jdbc/src/main/java/org/springframework/jdbc/object/SqlOperation.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -94,7 +94,7 @@ public abstract class SqlOperation extends RdbmsOperation {
 	 * with the given parameters.
 	 * @param params the parameter array (may be {@code null})
 	 */
-	protected final PreparedStatementSetter newPreparedStatementSetter(Object @Nullable [] params) {
+	protected final PreparedStatementSetter newPreparedStatementSetter(@Nullable Object @Nullable [] params) {
 		Assert.state(this.preparedStatementFactory != null, "No PreparedStatementFactory available");
 		return this.preparedStatementFactory.newPreparedStatementSetter(params);
 	}
@@ -104,7 +104,7 @@ public abstract class SqlOperation extends RdbmsOperation {
 	 * with the given parameters.
 	 * @param params the parameter array (may be {@code null})
 	 */
-	protected final PreparedStatementCreator newPreparedStatementCreator(Object @Nullable [] params) {
+	protected final PreparedStatementCreator newPreparedStatementCreator(@Nullable Object @Nullable [] params) {
 		Assert.state(this.preparedStatementFactory != null, "No PreparedStatementFactory available");
 		return this.preparedStatementFactory.newPreparedStatementCreator(params);
 	}
@@ -116,7 +116,7 @@ public abstract class SqlOperation extends RdbmsOperation {
 	 * the factory's, for example because of named parameter expanding)
 	 * @param params the parameter array (may be {@code null})
 	 */
-	protected final PreparedStatementCreator newPreparedStatementCreator(String sqlToUse, Object @Nullable [] params) {
+	protected final PreparedStatementCreator newPreparedStatementCreator(String sqlToUse, @Nullable Object @Nullable [] params) {
 		Assert.state(this.preparedStatementFactory != null, "No PreparedStatementFactory available");
 		return this.preparedStatementFactory.newPreparedStatementCreator(sqlToUse, params);
 	}

spring-jdbc/src/main/java/org/springframework/jdbc/object/SqlQuery.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -227,7 +227,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 		ParsedSql parsedSql = getParsedSql();
 		MapSqlParameterSource paramSource = new MapSqlParameterSource(paramMap);
 		String sqlToUse = NamedParameterUtils.substituteNamedParameters(parsedSql, paramSource);
-		Object[] params = NamedParameterUtils.buildValueArray(parsedSql, paramSource, getDeclaredParameters());
+		@Nullable Object[] params = NamedParameterUtils.buildValueArray(parsedSql, paramSource, getDeclaredParameters());
 		RowMapper<T> rowMapper = newRowMapper(params, context);
 		return getJdbcTemplate().query(newPreparedStatementCreator(sqlToUse, params), rowMapper);
 	}
@@ -238,7 +238,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * the SqlParameters. Primitive parameters must be represented by their Object wrapper
 	 * type. The ordering of parameters is not significant.
 	 */
-	public List<T> executeByNamedParam(Map<String, ?> paramMap) throws DataAccessException {
+	public List<T> executeByNamedParam(Map<String, ? extends @Nullable Object> paramMap) throws DataAccessException {
 		return executeByNamedParam(paramMap, null);
 	}
 
@@ -361,6 +361,6 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * but it can be useful for creating the objects of the result list.
 	 * @see #execute
 	 */
-	protected abstract RowMapper<T> newRowMapper(Object @Nullable [] parameters, @Nullable Map<?, ?> context);
+	protected abstract RowMapper<T> newRowMapper(@Nullable Object @Nullable [] parameters, @Nullable Map<?, ?> context);
 
 }

spring-jdbc/src/main/java/org/springframework/jdbc/object/SqlUpdate.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -20,6 +20,8 @@ import java.util.Map;
 
 import javax.sql.DataSource;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.dao.DataAccessException;
 import org.springframework.dao.InvalidDataAccessApiUsageException;
 import org.springframework.jdbc.JdbcUpdateAffectedIncorrectNumberOfRowsException;
@@ -252,7 +254,7 @@ public class SqlUpdate extends SqlOperation {
 		ParsedSql parsedSql = getParsedSql();
 		MapSqlParameterSource paramSource = new MapSqlParameterSource(paramMap);
 		String sqlToUse = NamedParameterUtils.substituteNamedParameters(parsedSql, paramSource);
-		Object[] params = NamedParameterUtils.buildValueArray(parsedSql, paramSource, getDeclaredParameters());
+		@Nullable Object[] params = NamedParameterUtils.buildValueArray(parsedSql, paramSource, getDeclaredParameters());
 		int rowsAffected = getJdbcTemplate().update(newPreparedStatementCreator(sqlToUse, params));
 		checkRowsAffected(rowsAffected);
 		return rowsAffected;
@@ -271,7 +273,7 @@ public class SqlUpdate extends SqlOperation {
 		ParsedSql parsedSql = getParsedSql();
 		MapSqlParameterSource paramSource = new MapSqlParameterSource(paramMap);
 		String sqlToUse = NamedParameterUtils.substituteNamedParameters(parsedSql, paramSource);
-		Object[] params = NamedParameterUtils.buildValueArray(parsedSql, paramSource, getDeclaredParameters());
+		@Nullable Object[] params = NamedParameterUtils.buildValueArray(parsedSql, paramSource, getDeclaredParameters());
 		int rowsAffected = getJdbcTemplate().update(newPreparedStatementCreator(sqlToUse, params), generatedKeyHolder);
 		checkRowsAffected(rowsAffected);
 		return rowsAffected;

spring-jdbc/src/main/java/org/springframework/jdbc/object/UpdatableSqlQuery.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -63,7 +63,7 @@ public abstract class UpdatableSqlQuery<T> extends SqlQuery<T> {
 	 * implementation of the {@code updateRow()} method.
 	 */
 	@Override
-	protected RowMapper<T> newRowMapper(Object @Nullable [] parameters, @Nullable Map<?, ?> context) {
+	protected RowMapper<T> newRowMapper(@Nullable Object @Nullable [] parameters, @Nullable Map<?, ?> context) {
 		return new RowMapperImpl(context);
 	}