Java 如何使用JDBC实现数据表的服务器端处理，以便进行分页？

我有一个带有DataTables服务器端处理和Oracle数据库的Spring Boot应用程序。实际上，我是从实现其中一个教程开始的。成功了。本教程使用JPA。我想用JDBC实现同样的功能。我制作了所有相应的类，存储库，新模型，使用相同的fild，但没有jpa。但当我试图获取数据时，它只允许我获取第一页，而没有机会访问第二页。下面我将发布原始代码和添加代码的摘录。因此，原始教程使用了以下类：

@Entity
@Table(name = "MYUSERS")
public class User {

    @Id
    @Column(name = "USER_ID")
    private Long id;

    @Column(name = "USER_NAME")
    private String name;

    @Column(name = "SALARY")
    private String salary;

...getters and setters
}

及

我用一个这样的类替换了这两个类：

public class NewUser {

    private Long id;
    private String name;
    private String salary;
    private Integer totalRecords;
    private Integer rn;

...getters and setters
}

public interface UserRepository extends JpaRepository<User, Long> {

    @Query(value = "SELECT * FROM MYUSERS", nativeQuery = true)
    List<User> findAllByUsernames(List<String> listOfUsernames);
}

@Repository
public class NewUserRepoImpl extends JdbcDaoSupport implements NewUserRepo {

    private static final String SELECT_ALL_SQL = "SELECT USER_ID as id, USER_NAME as name, SALARY as salary FROM MYUSERS";

    private final NamedParameterJdbcTemplate namedParameterJdbcTemplate;
    private final JdbcTemplate jdbctemplate;

    public NewUserRepoImpl(NamedParameterJdbcTemplate namedParameterJdbcTemplate, JdbcTemplate jdbctemplate, DataSource dataSource) {
        this.namedParameterJdbcTemplate = namedParameterJdbcTemplate;
        this.jdbctemplate = jdbctemplate;
        setDataSource(dataSource);
    }

    @Override
    public List<NewUser> findAll(PaginationCriteria pagination) {
        try {
            String paginatedQuery = AppUtil.buildPaginatedQueryForOracle(SELECT_ALL_SQL, pagination);
            return jdbctemplate.query(paginatedQuery, newUserRowMapper());
        } catch (DataAccessException e) {
            throw new EntityNotFoundException("No Entities Found");
        }
    }

    @Bean
    public RowMapper<NewUser> newUserRowMapper() {
        return (rs, i) -> {
            final NewUser newUser = new NewUser();
            newUser.setId(rs.getLong("ID"));
            newUser.setName(rs.getString("NAME"));
            newUser.setSalary(rs.getString("SALARY"));
            newUser.setTotalRecords(rs.getInt("TOTAL_RECORDS"));
            newUser.setTotalRecords(rs.getInt("RN"));
            return newUser;
        };
    }
}

表本身只有3个字段：id、name和salary，其他2个字段稍后创建和填充。 原始作者为用户提供的存储库如下所示：

public class NewUser {

    private Long id;
    private String name;
    private String salary;
    private Integer totalRecords;
    private Integer rn;

...getters and setters
}

public interface UserRepository extends JpaRepository<User, Long> {

    @Query(value = "SELECT * FROM MYUSERS", nativeQuery = true)
    List<User> findAllByUsernames(List<String> listOfUsernames);
}

@Repository
public class NewUserRepoImpl extends JdbcDaoSupport implements NewUserRepo {

    private static final String SELECT_ALL_SQL = "SELECT USER_ID as id, USER_NAME as name, SALARY as salary FROM MYUSERS";

    private final NamedParameterJdbcTemplate namedParameterJdbcTemplate;
    private final JdbcTemplate jdbctemplate;

    public NewUserRepoImpl(NamedParameterJdbcTemplate namedParameterJdbcTemplate, JdbcTemplate jdbctemplate, DataSource dataSource) {
        this.namedParameterJdbcTemplate = namedParameterJdbcTemplate;
        this.jdbctemplate = jdbctemplate;
        setDataSource(dataSource);
    }

    @Override
    public List<NewUser> findAll(PaginationCriteria pagination) {
        try {
            String paginatedQuery = AppUtil.buildPaginatedQueryForOracle(SELECT_ALL_SQL, pagination);
            return jdbctemplate.query(paginatedQuery, newUserRowMapper());
        } catch (DataAccessException e) {
            throw new EntityNotFoundException("No Entities Found");
        }
    }

    @Bean
    public RowMapper<NewUser> newUserRowMapper() {
        return (rs, i) -> {
            final NewUser newUser = new NewUser();
            newUser.setId(rs.getLong("ID"));
            newUser.setName(rs.getString("NAME"));
            newUser.setSalary(rs.getString("SALARY"));
            newUser.setTotalRecords(rs.getInt("TOTAL_RECORDS"));
            newUser.setTotalRecords(rs.getInt("RN"));
            return newUser;
        };
    }
}

public interface UserRepository扩展了JpaRepository{
@查询（value=“SELECT*FROM MYUSERS”，nativeQuery=true）
列出findAllByUsernames（列出用户名称列表）；
}

我自己的存储库如下所示：

public class NewUser {

    private Long id;
    private String name;
    private String salary;
    private Integer totalRecords;
    private Integer rn;

...getters and setters
}

public interface UserRepository extends JpaRepository<User, Long> {

    @Query(value = "SELECT * FROM MYUSERS", nativeQuery = true)
    List<User> findAllByUsernames(List<String> listOfUsernames);
}

@Repository
public class NewUserRepoImpl extends JdbcDaoSupport implements NewUserRepo {

    private static final String SELECT_ALL_SQL = "SELECT USER_ID as id, USER_NAME as name, SALARY as salary FROM MYUSERS";

    private final NamedParameterJdbcTemplate namedParameterJdbcTemplate;
    private final JdbcTemplate jdbctemplate;

    public NewUserRepoImpl(NamedParameterJdbcTemplate namedParameterJdbcTemplate, JdbcTemplate jdbctemplate, DataSource dataSource) {
        this.namedParameterJdbcTemplate = namedParameterJdbcTemplate;
        this.jdbctemplate = jdbctemplate;
        setDataSource(dataSource);
    }

    @Override
    public List<NewUser> findAll(PaginationCriteria pagination) {
        try {
            String paginatedQuery = AppUtil.buildPaginatedQueryForOracle(SELECT_ALL_SQL, pagination);
            return jdbctemplate.query(paginatedQuery, newUserRowMapper());
        } catch (DataAccessException e) {
            throw new EntityNotFoundException("No Entities Found");
        }
    }

    @Bean
    public RowMapper<NewUser> newUserRowMapper() {
        return (rs, i) -> {
            final NewUser newUser = new NewUser();
            newUser.setId(rs.getLong("ID"));
            newUser.setName(rs.getString("NAME"));
            newUser.setSalary(rs.getString("SALARY"));
            newUser.setTotalRecords(rs.getInt("TOTAL_RECORDS"));
            newUser.setTotalRecords(rs.getInt("RN"));
            return newUser;
        };
    }
}

@存储库
公共类NewUserRepoImpl扩展JDBCDAO支持实现NewUserRepo{
private static final String SELECT_ALL_SQL=“SELECT USER_ID as ID，USER_NAME as NAME，SALARY as SALARY FROM MYUSERS”；
私有最终名称ParameterJDBCTemplate名称ParameterJDBCTemplate；
私有最终JdbcTemplate JdbcTemplate；
public NewUserRepoImpl（NamedParameterJdbcTemplate NamedParameterJdbcTemplate，JdbcTemplate JdbcTemplate，DataSource DataSource）{
this.namedParameterJdbcTemplate=namedParameterJdbcTemplate；
this.jdbctemplate=jdbctemplate；
setDataSource（数据源）；
}
@凌驾
公共列表findAll（分页标准分页）{
试一试{
字符串paginatedQuery=AppUtil.buildPaginatedQueryForOracle（选择_ALL_SQL，分页）；
返回jdbctemplate.query（paginatedQuery，newUserRowMapper（））；
}捕获（数据访问异常）{
抛出新EntityNotFoundException（“未找到实体”）；
}
}
@豆子
公共行映射器newUserRowMapper（）{
返回（rs，i）->{
final NewUser NewUser=new NewUser（）；
newUser.setId（rs.getLong（“ID”）；
newUser.setName（rs.getString（“NAME”）；
newUser.setSalary（rs.getString（“SALARY”）；
newUser.setTotalRecords（rs.getInt（“TOTAL_记录”）；
newUser.setTotalRecords（rs.getInt（“RN”）；
返回新用户；
};
}
}

buildPaginatedQueryForOracle东西转换我的查询，并允许它获取totalRecords和rn。在下面，我将为orifinal和我的查询发布它的输出（它们是相同的，我选中了）

那么，主要的部分，控制器。为了调试目的，我暂时将新旧部分放在其中，只返回其中一个结果：

@RequestMapping(value="/users/paginated/orcl", method=RequestMethod.GET)
    @ResponseBody
    public String listUsersPaginatedForOracle(HttpServletRequest request, HttpServletResponse response, Model model) {

        DataTableRequest<User> dataTableInRQ = new DataTableRequest<User>(request);
        System.out.println(new Gson().toJson(dataTableInRQ));
        DataTableRequest<NewUser> dataTableInRQNew = new DataTableRequest<NewUser>(request);
        System.out.println(new Gson().toJson(dataTableInRQNew));
        PaginationCriteria pagination = dataTableInRQ.getPaginationRequest();
        System.out.println(new Gson().toJson(pagination));
        PaginationCriteria paginationNew = dataTableInRQNew.getPaginationRequest();
        System.out.println(new Gson().toJson(paginationNew));
        String baseQuery = "SELECT USER_ID as id, USER_NAME as name, SALARY as salary FROM MYUSERS";
        String paginatedQuery = AppUtil.buildPaginatedQueryForOracle(baseQuery, pagination);
        String paginatedQueryNew = AppUtil.buildPaginatedQueryForOracle(baseQuery, paginationNew);

        System.out.println(paginatedQuery);
        System.out.println(paginatedQueryNew);

        Query query = entityManager.createNativeQuery(paginatedQuery, UserModel.class);
        System.out.println("Query:");
        System.out.println(query);

        @SuppressWarnings("unchecked")
        List<UserModel> userList = query.getResultList();
        System.out.println(new Gson().toJson(userList));

        @SuppressWarnings("unchecked")
        List<NewUser> userListNew = newUserRepo.findAll(paginationNew);     
        System.out.println(new Gson().toJson(userListNew));

        DataTableResults<UserModel> dataTableResult = new DataTableResults<UserModel>();
        DataTableResults<NewUser> dataTableResultNew = new DataTableResults<NewUser>();
        dataTableResult.setDraw(dataTableInRQ.getDraw());
        dataTableResultNew.setDraw(dataTableInRQNew.getDraw());
        dataTableResult.setListOfDataObjects(userList);
        dataTableResultNew.setListOfDataObjects(userListNew);
        if (!AppUtil.isObjectEmpty(userList)) {
            dataTableResult.setRecordsTotal(userList.get(0).getTotalRecords()
                    .toString());
            if (dataTableInRQ.getPaginationRequest().isFilterByEmpty()) {
                dataTableResult.setRecordsFiltered(userList.get(0).getTotalRecords()
                        .toString());
            } else {
                dataTableResult.setRecordsFiltered(Integer.toString(userList.size()));
            }
        }
        if (!AppUtil.isObjectEmpty(userListNew)) {
            dataTableResultNew.setRecordsTotal(userListNew.get(0).getTotalRecords()
                    .toString());
            if (dataTableInRQ.getPaginationRequest().isFilterByEmpty()) {
                dataTableResultNew.setRecordsFiltered(userListNew.get(0).getTotalRecords()
                        .toString());
            } else {
                dataTableResultNew.setRecordsFiltered(Integer.toString(userListNew.size()));
            }
        }
        System.out.println(new Gson().toJson(dataTableResult));
        System.out.println(new Gson().toJson(dataTableResultNew));
        return new Gson().toJson(dataTableResult);
    }

@RequestMapping（value=“/users/paginated/orcl”，method=RequestMethod.GET）
@应答器
公共字符串listUsersPaginatedForOracle（HttpServletRequest请求，HttpServletResponse响应，模型）{
DataTableRequest dataTableInRQ=新的DataTableRequest（请求）；
System.out.println（新的Gson（）.toJson（dataTableInRQ））；
DataTableRequest dataTableInRQNew=新DataTableRequest（请求）；
System.out.println（new Gson（）.toJson（dataTableInRQNew））；
PaginationCriteria pagination=dataTableInRQ.getPaginationRequest（）；
System.out.println（新的Gson（）.toJson（分页））；
PaginationCriteria paginationNew=dataTableInRQNew.getPaginationRequest（）；
System.out.println（新的Gson（）.toJson（paginationNew））；
String baseQuery=“从MYUSERS中选择用户ID作为ID，用户名称作为名称，薪资作为薪资”；
字符串paginatedQuery=AppUtil.buildPaginatedQueryForOracle（baseQuery，分页）；
字符串paginatedQueryNew=AppUtil.buildpaginatedqueryforracle（baseQuery，paginationNew）；
System.out.println（分页查询）；
System.out.println（分页查询新建）；
Query Query=entityManager.createNativeQuery（paginatedQuery，UserModel.class）；
System.out.println（“查询：”）；
System.out.println（查询）；
@抑制警告（“未选中”）
List userList=query.getResultList（）；
System.out.println（新的Gson（）.toJson（userList））；
@抑制警告（“未选中”）
List userListNew=newUserRepo.findAll（paginationNew）；
System.out.println（new Gson（）.toJson（userListNew））；
DataTableResults dataTableResult=新建DataTableResults（）；
DataTableResults dataTableResultNew=新建DataTableResults（）；
setDraw（dataTableInRQ.getDraw（））；
dataTableResultNew.setDraw（dataTableInRQNew.getDraw（））；
dataTableResult.setListOfDataObjects（userList）；
dataTableResultNew.setListOfDataObjects（userListNew）；
如果（！AppUtil.isObjectEmpty（userList））{
dataTableResult.setRecordsTotal（userList.get（0.getTotalRecords）（）
.toString（））；
如果（dataTableInRQ.getPaginationRequest（）.isFilterByEmpty（））{
dataTableResult.setRecordsFiltered（userList.get（0）.getTotalRecords（）
.toString（））；
}否则{
dataTableResult.setRecordsFiltered（Integer.toString（userList.size（））；
}
}
如果（！AppUtil.isObjectEmpty（userListNew））{
dataTableResultNew.setRecordsTotal（userListNew.get（0.getTotalRecords）（）
.toString（））；
如果（dataTableInRQ.getPaginationRequest（）.isFilterByEmpty（））{
dataTableResultNew.setRecordsFiltered（userListNew.get（0）.getTotalRecords（）
.toString（））；
}否则{
dataTableResultNew.setRecordsFiltered（Integer.toString（userListNew.size（））；
}
}
System.out.prin