Cannot use object properties correctly if SPRING_NAMED_PARAMETER

I using below version:

1. org.mybatis.scripting:mybatis-thymeleaf:1.0.4
2. org.springframework:spring-jdbc:6.0.9
3. java 17

This issue occurs when using object properties with mb:p.

Probably because Spring JDBC does not allow you to specify properties of objects.

Exception thrown

java.lang.RuntimeException: org.springframework.dao.InvalidDataAccessApiUsageException: No value supplied for the SQL parameter 'person.id': No value registered for key 'person.id'

This issue can be avoided by using mb:bind="person.id=${person.id}".

However, it cannot be used inside th:each. (Correctly, it will be overwritten by the value from the last loop.)

This causes the "Bulk insert" section of the document to fail.

The code is as follows.

Domain objects

public class Person {

        private String id;
        private String name;
        private String birthDate;

        public String getId() {
            return id;
        }
        public String getName() {
            return name;
        }
        public String getBirthDate() {
            return birthDate;
        }
}

Sql Template

INSERT INTO
    
    person

    VALUES(
        /*[# mb:p="person.id"/]*/,
        /*[# mb:p="person.name"/]*/,
        /*[# mb:p="person.birthDate"/]*/
    )

;

Creating SqlGenerator Method

public SqlGenerator createSqlGenerator() {

        SqlGeneratorConfig config = SqlGeneratorConfig.newInstanceWithCustomizer(c ->
            c.getDialect().setBindVariableRenderInstance(BindVariableRender.BuiltIn.SPRING_NAMED_PARAMETER)
        );

        return new SqlGenerator(config);
}

Run query Method

public int insert(String sqlTemplate, SqlGenerator gen, NamedParameterJdbcTemplate jdbc) {
        final Person person = new Person();
        person.id = "ID-001";
        person.name = "John Doe";
        person.birthDate = "2001-01-01"; 

        final Map<String, Object> params = new HashMap<>();
        params.put("person", person);

        System.out.println(params);

        final String jdbcSql = gen.generate(sqlTemplate, params, params::put);
        
        System.out.println(jdbcSql);
        System.out.println(params);

        return jdbc.update(jdbcSql, params);
}

Reproduce the failure through SqlGenerator with SPRING_NAMED_PARAMETER and NamedParameterJdbcTemplate, using the object-property parameters shown in the issue. Trace how mb:p names are registered and resolved, then verify that object properties work inside the documented Bulk insert loop without requiring mb:bind.