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我有一个简单的查询，如果在方法中指定了各种条件参数，它可以采用：

String sql = "SELECT * FROM TABLE WHERE userId = ?";

ArrayList<Object> dataBindings = new ArrayList<Object>();
dataBindings.add(userId);

if(startDate != null && !startDate.equalsIgnoreCase("")){
    SQL += " AND datev BETWEEN ? AND ?";
    dataBindings.add(startDate);
    dataBindings.add(endDate);
}

if (argn > 0) {
    SQL += " AND argn = ?";
    dataBindings.add(argn);
}


List<SomeObject> someObjectList = this.jdbcTemplate.query(SQL, new RowMapper<SomeObject>() {
        // using anonymous inner class RowMapper here
        public SomeObject mapRow(ResultSet rs, int rowNum) throws SQLException {
            SomeObject o = new SomeObject();
            o.setId(rs.getInt("idobj"));                
            ...
            return s;
        }
}, dataBindings.toArray());

但我得到了错误：No operator matches the given name and argument type(s). You might need to add explicit type casts.

我必须指定每个参数的类型，但是当我将对象数组传递给 时query()，它无法确定哪个参数是字符串或整数。

我怎么能做到这一点？

编辑：我尝试过这种方式，但我认为它可能更优雅，因为我每个条件至少检查两次，因为如果不再次检查这些条件，我将无法知道要传递的参数的索引

try {
    InitialContext context = new InitialContext();
    ComboPooledDataSource dataSource = (ComboPooledDataSource) context.lookup("jdbc/myDB");
    PreparedStatement ps = dataSource.getConnection().prepareStatement(SQL);
    ps.setLong(1, userId);

    if(startDate != null && !startDate.equalsIgnoreCase("")) {
        ps.setString(2, startDate);
        ps.setString(3, endDate);
    }

    if (argn > 0) {
        if(startDate != null && !startDate.equalsIgnoreCase("")) {
            ps.setInt(3, argn);
        } else {
            ps.setInt(2, argn);
        }
    }
} catch (SQLException e) {
    e.printStackTrace();
}

而且我不能在这里使用 RowMapper

所以我可以这样做：

final String finalSqlQuery = SQL;
jdbcTemplate.query(new PreparedStatementCreator() {

        @Override
        public PreparedStatement createPreparedStatement(Connection con)
                            throws SQLException {
             PreparedStatement ps = con.prepareStatement(finalSqlQuery);
             if(startDate != null && !startDate.equalsIgnoreCase("")) {
                   ps.setString(2, startDate);
                   ps.setString(3, endDate);
             }

             if (argn > 0) {
                  if(startDate != null && !startDate.equalsIgnoreCase("")) {
                      ps.setInt(3, argn);
                  } else {
                      ps.setInt(2, argn);
                  }
             }

        }
    }, new RowMapper<SomeObject>() {

            public SomeObject mapRow(ResultSet rs, int rowNum) throws SQLException {
                SomeObject o = new SomeObject();
                o.setId(rs.getInt("idobj"));                
                ...
                return s;
           }
    });

但是通过再次检查条件来确定参数的索引对我来说似乎真的很难看

4

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