Are enums supported by JDBC?

问题

I really can't find a nice enum JDBC mapping example. Is enum actually supported by JDBC?

I am working with MySQL. I have an enum column, and would like to map to some Java enum.

回答1:

JDBC does not support enums.

You can convert a string to an enum though, so if you have a Java enum you can do something like

 MyEnum enumVal =  MyEnum.valueOf(rs.getString("EnumColumn"));

You'll have to keep your java enum and mysql enum in sync though. MyEnum.valueOf() can throw IllegalArgumentException if there's no mapping from the string, or NullPointerException if you get a null value from the db.

回答2:

Here is some generic solution were are using in converting JDBC values to Java enums.

param = Enum.valueOf((Class<? extends Enum>)dbField.getField().getType(), (String) param);

where param is the value of the field in the db , and the dbField is the java.reflect.util.Field , where to put the value to

来源：https://stackoverflow.com/questions/3155967/are-enums-supported-by-jdbc