io.r2dbc.spi

Interface RowMetadata

public interface RowMetadata

Represents the metadata for a row of the results returned from a query. Metadata for columns can be either retrieved by specifying a column name or the column index. Columns indexes are 0-based. Column names do not necessarily reflect the column names how they are in the underlying tables but rather how columns are represented (e.g. aliased) in the result.

Method Summary

Modifier and Type	Method and Description
default boolean	contains(String columnName) Returns whether this object contains metadata for columnName.
ColumnMetadata	getColumnMetadata(int index) Returns the ColumnMetadata for one column in this row.
ColumnMetadata	getColumnMetadata(String name) Returns the ColumnMetadata for one column in this row.
List<? extends ColumnMetadata>	getColumnMetadatas() Returns the ColumnMetadata for all columns in this row.
Collection<String>	getColumnNames() Deprecated. since 0.9 for removal. Use contains(String) or getColumnMetadatas() instead.

Method Detail

getColumnMetadata

ColumnMetadata getColumnMetadata(int index)

Returns the ColumnMetadata for one column in this row.

Parameters:

index - the column index starting at 0

Returns:

the ColumnMetadata for one column in this row

Throws:

ArrayIndexOutOfBoundsException - if the index is less than zero or greater than the number of available columns.

getColumnMetadata

ColumnMetadata getColumnMetadata(String name)

Returns the ColumnMetadata for one column in this row.

Parameters:

name - the name of the column. Column names are case insensitive. When a get method contains several columns with same name, then the value of the first matching column will be returned

Returns:

the ColumnMetadata for one column in this row

Throws:

IllegalArgumentException - if name is null

NoSuchElementException - if there is no column with the name

getColumnMetadatas

List<? extends ColumnMetadata> getColumnMetadatas()

Returns the ColumnMetadata for all columns in this row.

Returns:

the ColumnMetadata for all columns in this row

getColumnNames

@Deprecated
Collection<String> getColumnNames()

Deprecated. since 0.9 for removal. Use contains(String) or getColumnMetadatas() instead.

Returns an unmodifiable collection of column names.

Any attempts to modify the returned collection, whether direct or via its iterator, result in an UnsupportedOperationException.

The iteration order of the column names depends on the actual query result. Column names may appear multiple times if the result specifies multiple columns with the same name. Lookups through Collection.contains(Object) are case-insensitive. Implementations may enhance comparison sorting rules with escape characters to enforce a particular mode of comparison when querying for presence/absence of a column.

Returns:

the column names.

contains

default boolean contains(String columnName)

Returns whether this object contains metadata for columnName. Lookups are case-insensitive. Implementations may allow escape characters to enforce a particular mode of comparison when querying for presence/absence of a column.

Returns:

true if this object contains metadata for columnName; false otherwise.

Since:

0.9