Module com.aoindustries.aoserv.client

Package com.aoindustries.aoserv.client

Class DbEnum

java.lang.Object

com.aoindustries.aoserv.client.DbEnum

public final class DbEnum
extends Object

A registry of converters from Java Enum to/from the underlying PostgreSQL enum value. All enum types used for implementations of Type.ENUM must be registered.

Author:

AO Industries, Inc.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	DbEnum.FromDbValue<E extends Enum<?>>
static interface	DbEnum.ToDbValue<E extends Enum<?>>

Method Summary

Modifier and Type	Method	Description
static <E extends Enum<?>> E	fromDbValue(Class<E> enumClass, String dbValue)	Maps a database value to the matching Enum.
static <E extends Enum<?>> void	register(Class<E> enumClass)	Registers a new type with default DbEnum.ToDbValue of Enum.name() and DbEnum.FromDbValue of Enum.valueOf(java.lang.Class, java.lang.String).
static <E extends Enum<?>> void	register(Class<E> enumClass, DbEnum.ToDbValue<E> toDbValue, DbEnum.FromDbValue<E> fromDbValue)	Registers a new type with provided DbEnum.ToDbValue and DbEnum.FromDbValue.
static <E extends Enum<?>> String	toDbValue(E value)	Maps an Enum value to the matching database value.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

register

public static <E extends Enum<?>> void register(Class<E> enumClass,
 DbEnum.ToDbValue<E> toDbValue,
 DbEnum.FromDbValue<E> fromDbValue)

Registers a new type with provided DbEnum.ToDbValue and DbEnum.FromDbValue.

register

public static <E extends Enum<?>> void register(Class<E> enumClass)

Registers a new type with default DbEnum.ToDbValue of Enum.name() and DbEnum.FromDbValue of Enum.valueOf(java.lang.Class, java.lang.String).

toDbValue

public static <E extends Enum<?>> String toDbValue(E value)
                                            throws IllegalStateException

Maps an Enum value to the matching database value.

This does not directly match the value from the database, but will match the underlying database value at the time of this client schema version. In other words, the underlying database may change, but this value will stay constant within a single schema version.

Parameters:

value - The Java enum value, may be null

Returns:

The Java enum value corresponding to the give database value or null when dbValue == null.

Throws:

IllegalStateException - if DbEnum.ToDbValue not registered or DbEnum.ToDbValue returns unexpected null

fromDbValue

public static <E extends Enum<?>> E fromDbValue(Class<E> enumClass,
 String dbValue)
                                         throws IllegalStateException,
IllegalArgumentException

Maps a database value to the matching Enum.

This does not directly match the value from the database, but will match the underlying database value at the time of this client schema version. In other words, the underlying database may change, but this value will stay constant within a single schema version.

Parameters:

dbValue - The database value, may be null

Returns:

The Java enum value corresponding to the give database value or null when dbValue == null.

Throws:

IllegalStateException - if DbEnum.FromDbValue not registered or DbEnum.FromDbValue returns unexpected null

IllegalArgumentException - when unable to map the database value to the Enum.