DateTimeTypeHandler

mysql-timestimp-------model-DateTime(jodatime)

 public class DataTimeTypeHandler extends BaseTypeHandler<DateTime> {
     @Override
     public void setNonNullParameter(PreparedStatement ps, int i, DateTime parameter, JdbcType jdbcType) throws SQLException {
         ps.setTimestamp(i, new Timestamp(parameter.getMillis()));
     }

     @Override
     public DateTime getNullableResult(ResultSet rs, String columnName) throws SQLException {
         Timestamp timestamp = rs.getTimestamp(columnName);
         if (timestamp == null) {
             return DateTime.now();
         }
         return new DateTime(timestamp);
     }

     @Override
     public DateTime getNullableResult(ResultSet rs, int columnIndex) throws SQLException {
         Timestamp timestamp = rs.getTimestamp(columnIndex);
         if (timestamp == null) {
             return DateTime.now();
         }
         return new DateTime(timestamp);
     }

     @Override
     public DateTime getNullableResult(CallableStatement cs, int columnIndex) throws SQLException {
         Timestamp timestamp = cs.getTimestamp(columnIndex);
         if (timestamp == null) {
             return DateTime.now();
         }
         return new DateTime(timestamp);
     }
 }

<typeHandlers>
　　handler="com.qunar.fresh.typehandler.DataTimeTypeHandler" javaType="org.joda.time.DateTime"/>
</typeHandlers>

这样在插入或是查找的时候不会出现null的情况。

自己写typeHandler，其他类型转mysql字段类型也一样，在这里不一一细说。