现在有一个需求，mysql查询记录映射到List<pojo>中，其中pojo某个字段是Map类型，需要将查询记录中这列映射到Map中，否则默认会当作String映射，以下为当前代码：

public List
     
       mapRersultSetToObject(ResultSet rs, Class outputClass) {        List
      
        outputList = null;        try {            // make sure resultset is not null            if (rs != null) {                // check if outputClass has 'Entity' annotation                if (outputClass.isAnnotationPresent(Entity.class)) {                    // get the resultset metadata                    ResultSetMetaData rsmd = rs.getMetaData();                    // get all the attributes of outputClass                    Field[] fields = outputClass.getDeclaredFields();                    while (rs.next()) {                        T bean = (T) outputClass.newInstance();                        for (int _iterator = 0; _iterator < rsmd.getColumnCount(); _iterator++) {                            // getting the SQL column name                            String columnName = rsmd.getColumnName(_iterator + 1);                            // reading the value of the SQL column                            Object columnValue = rs.getObject(_iterator + 1);                            // iterating over outputClass attributes to check if                            // any attribute has 'Column' annotation with                            // matching 'name' value                            for (Field field : fields) {                                if (field.isAnnotationPresent(Column.class)) {                                    Column column = field.getAnnotation(Column.class);                                    if (column.name().equalsIgnoreCase(columnName) && columnValue != null) {                                        BeanUtils.setProperty(bean, field.getName(), columnValue);                                        break;                                    }                                }                            }                        }                        if (outputList == null) {                            outputList = new ArrayList
       
        ();                        }                        outputList.add(bean);                    }                } else {                    // throw some error                }            } else {                return null;            }        }
       
      
     

解决方案，如果设置属性时每次都检查字段类型，效率会比较低，通过发生异常捕获，然后再转化的方式，如下代码所示：

if (column.name().equalsIgnoreCase(columnName) && columnValue != null) {                                        try{                                            BeanUtils.setProperty(bean, field.getName(), columnValue);                                        }catch (ConversionException exception){                                            if(field.getType().equals(Map.class)){                                                BeanUtils.setProperty(bean, field.getName(), JSON.parse(String.valueOf(columnValue)));                                            }                                        }                                        break;                                    }