Interface DatabaseClient

All Superinterfaces:

ConnectionAccessor

public interface DatabaseClient
extends ConnectionAccessor

A non-blocking, reactive client for performing database calls with Reactive Streams back pressure. Provides a higher level, common API over R2DBC client libraries. Propagates DataAccessException variants for errors.

Use the static factory method create(ConnectionFactory) or obtain a builder to create an instance.

Usage example:

ConnectionFactory factory = …

DatabaseClient client = DatabaseClient.create(factory);
Mono<Actor> actor = client.sql("select first_name, last_name from t_actor")
    .map(row -> new Actor(row.get("first_name", String.class),
         row.get("last_name", String.class)))
    .first();

Since:

5.3

Author:

Mark Paluch, Juergen Hoeller, Brian Clozel

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	DatabaseClient.Builder	A mutable builder for creating a DatabaseClient.
static interface	DatabaseClient.GenericExecuteSpec	Contract for specifying an SQL call along with options leading to the execution.

Method Summary

Modifier and Type	Method	Description
static DatabaseClient.Builder	builder()	Obtain a DatabaseClient builder.
static DatabaseClient	create(ConnectionFactory factory)	Create a DatabaseClient that will use the provided ConnectionFactory.
ConnectionFactory	getConnectionFactory()	Get the ConnectionFactory that this client uses.
DatabaseClient.GenericExecuteSpec	sql(String sql)	Specify a static sql statement to run.
DatabaseClient.GenericExecuteSpec	sql(Supplier<String> sqlSupplier)	Specify an SQL supplier that provides SQL to run.

Methods inherited from interface ConnectionAccessor

inConnection, inConnectionMany

Method Details

getConnectionFactory

ConnectionFactory getConnectionFactory()

Get the ConnectionFactory that this client uses.

Returns:

the connection factory

sql

DatabaseClient.GenericExecuteSpec sql(String sql)

Specify a static sql statement to run. Contract for specifying an SQL call along with options leading to the execution. The SQL string can contain either native parameter bind markers or named parameters (for example, :foo, :bar) when NamedParameterExpander is enabled.

Parameters:

sql - the SQL statement

Returns:

a new DatabaseClient.GenericExecuteSpec

See Also:

• NamedParameterExpander
• DatabaseClient.Builder.namedParameters(boolean)

sql

DatabaseClient.GenericExecuteSpec sql(Supplier<String> sqlSupplier)

Specify an SQL supplier that provides SQL to run. Contract for specifying an SQL call along with options leading to the execution. The SQL string can contain either native parameter bind markers or named parameters (for example, :foo, :bar) when NamedParameterExpander is enabled.

Accepts PreparedOperation as SQL and binding Supplier.

DatabaseClient implementations should defer the resolution of the SQL string as much as possible, ideally up to the point where a Subscription happens. This is the case for the default implementation.

Parameters:

sqlSupplier - a supplier for the SQL statement

Returns:

a new DatabaseClient.GenericExecuteSpec

See Also:

• NamedParameterExpander
• DatabaseClient.Builder.namedParameters(boolean)
• PreparedOperation

create

static DatabaseClient create(ConnectionFactory factory)

Create a DatabaseClient that will use the provided ConnectionFactory.

Parameters:

factory - the ConnectionFactory to use for obtaining connections

Returns:

a new DatabaseClient; never null

builder

static DatabaseClient.Builder builder()

Obtain a DatabaseClient builder.