Interface CustomColumnMapper

public interface CustomColumnMapper

Enables per-column ResultSet mapping customization via ResultSetMapper.

Since:

3.0.0

Author:

Mark Allen

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	CustomColumnMapper.MappingResult	Result of a custom column mapping attempt.

Method Summary

Modifier and Type	Method	Description
Boolean	appliesTo(TargetType targetType)	Specifies which types this mapper should handle.
CustomColumnMapper.MappingResult	map(StatementContext<?> statementContext, ResultSet resultSet, Object resultSetValue, TargetType targetType, Integer columnIndex, String columnLabel, InstanceProvider instanceProvider)	Perform custom mapping of a ResultSet column: given a resultSetValue, optionally return an instance of targetType instead.

Method Details

map

@Nonnull
CustomColumnMapper.MappingResult map(@Nonnull
 StatementContext<?> statementContext,
 @Nonnull
 ResultSet resultSet,
 @Nonnull
 Object resultSetValue,
 @Nonnull
 TargetType targetType,
 @Nonnull
 Integer columnIndex,
 @Nullable
 String columnLabel,
 @Nonnull
 InstanceProvider instanceProvider)
                              throws SQLException

Perform custom mapping of a ResultSet column: given a resultSetValue, optionally return an instance of targetType instead.

This method is only invoked when resultSetValue is non-null.

Parameters:

statementContext - current SQL context

resultSet - the ResultSet from which data was read

resultSetValue - the already-read value from the ResultSet, to be optionally converted to an instance of targetType

targetType - the type to which the resultSetValue should be converted

columnIndex - 1-based column index

columnLabel - normalized column label, if available

instanceProvider - instance-creation factory, may be used to instantiate values

Returns:

the result of the custom column mapping operation - either CustomColumnMapper.MappingResult.of(Object) to indicate a successfully-mapped value or CustomColumnMapper.MappingResult.fallback() if Pyranid should fall back to the registered ResultSetMapper mapping behavior.

Throws:

SQLException - if an error occurs during mapping

appliesTo

@Nonnull
Boolean appliesTo(@Nonnull
 TargetType targetType)

Specifies which types this mapper should handle.

For example, if this mapper should apply when marshaling to MyCustomType, this method could return targetType.matchesClass(MyCustomType.class).

For parameterized types like List<UUID>, this method could return targetType.matchesParameterizedType(List.class, UUID.class).

Parameters:

targetType - the target type to evaluate - should this mapper handle it or not?

Returns:

true if this mapper should handle the type, false otherwise.