[GitHub] [incubator-shardingsphere] sunbufu commented on issue #2604: The query entity throws an exception when a boolean property exists in the entity

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sunbufu commented on issue #2604: The query entity throws an exception when a boolean property exists in the entity
URL: https://github.com/apache/incubator-shardingsphere/issues/2604#issuecomment-508970554
 
 
   In my opinion, the purpose of `JDBC` is resolve different databases's compatibility. so `ResultSet` defined some method like `getBytes()`, `getBoolean()` and etc to help us get object with **expected java type**. 
   `ShardingSphere` work on dataSource, and defined `ResultSet` too, like `ShardingResultSet` and `EncryptResultSet`. but `ShardingSphere` use **database column type** in place of **expected java type**. 
   There are some codes in `StreamQueryResult`, we can see `getValue()` **do nothing** with `final Class<?> type`.
   ```java
   @Override
   public Object getValue(final int columnIndex, final Class<?> type) throws SQLException {
       return decrypt(columnIndex, QueryResultUtil.getValue(resultSet, columnIndex));
   }
   ```
   And in `QueryResultUtil`, `getValueByColumnType()` get **database column type** from `resultSet. metaData` and use it for `getXXX()` selection.
   ```java
   public static Object getValueByColumnType(final ResultSet resultSet, final int columnIndex) throws SQLException {
           ResultSetMetaData metaData = resultSet.getMetaData();
           switch (metaData.getColumnType(columnIndex)) {
               case Types.BIT:
                   return resultSet.getBytes(columnIndex);
               case Types.BOOLEAN:
                   return resultSet.getBoolean(columnIndex);
               case Types.TINYINT:
                   return resultSet.getByte(columnIndex);
               ...
           }
       }
   ```
   Usually it's okay, but when we use mysql and call some special methods such as `getBoolean()`, our **expected java type** is boolean,  **database column type** is not boolean. 
   so I think we should pass on the **expected java type**, and use it for `getXXX()` selection.
   Can I send a PR ?

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