Review ParameterizedPreparedStatementSetter argument nullability

[vpavic]

Commit a61b297#diff-d1e8483d1c981021eda9e2ef12138d8732b1711cc16c1438f041398f5d90be8f declared ParameterizedPreparedStatementSetter argument as @Nullable, which causes nullability warnings in user code.

This is the only usage of ParameterizedPreparedStatementSetter in Framework's codebase:

spring-framework/spring-jdbc/src/main/java/org/springframework/jdbc/core/JdbcTemplate.java

Lines 1089 to 1103 in ad22a99

	@Override
	public <T> int[][] batchUpdate(String sql, Collection<T> batchArgs, int batchSize,
	ParameterizedPreparedStatementSetter<T> pss) throws DataAccessException {
	if (logger.isDebugEnabled()) {
	logger.debug("Executing SQL batch update [" + sql + "] with a batch size of " + batchSize);
	}
	int[][] result = execute(sql, (PreparedStatementCallback<int[][]>) ps -> {
	List<int[]> rowsAffected = new ArrayList<>();
	try {
	boolean batchSupported = JdbcUtils.supportsBatchUpdates(ps.getConnection());
	int n = 0;
	for (T obj : batchArgs) {
	pss.setValues(ps, obj);
	n++;

Looking at JdbcTemplate#batchUpdate argument batchArgs, it doesn't declare collection elements as nullable, so perhaps that should translate to ParameterizedPreparedStatementSetter argument as well? In any case, I believe Framework should provide some guarantees here so that it doesn't burden user code with null-checks.