net.yetamine.osgi.jdbc.package-info Maven / Gradle / Ivy
/*
* Copyright 2016 Yetamine
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* Support for JDBC drivers in OSGi
*
* This bundle provides support for replacing {@link java.sql.DriverManager} in
* OSGi environment, while allowing JDBC drivers and clients to run in an OSGi
* container with no code modifications (except for providing the code as OSGi
* bundles with the necessary manifest headers).
*
* Implementation details
*
* The support, provided by this bundle, installs hooks to intercept calls from
* both drivers and clients to {@link java.sql.DriverManager} and redirects the
* driver- and connection-related calls to surrogate implementations, which are
* OSGi-friendly. This is achieved by a weaving hook that patches those classes
* on-the-fly. In order to support drivers provided by bootstrap delegation,
* {@link java.sql.DriverManager} can be used as a fallback.
*
*
* The other hook, installed by this bundle, scans other bundles for declaring
* {@link java.sql.Driver} implementations for {@link java.util.ServiceLoader}.
* These classes are loaded (after weaving to use the surrogate implementation)
* to trigger the driver registration. The drivers, registered as the result of
* this action, are published as OSGi services.
*
*
* The described approach has some limitations: it can't handle non-static code
* that invokes {@link java.sql.DriverManager} via reflection or any code which
* can't be processed by the weaving hook for any reasons.
*
*
Published interfaces
*
* {@link net.yetamine.osgi.jdbc.DriverProvider} provides an imitation of the
* subset of {@link java.sql.DriverManager}'s methods which deals with making
* connections. The JDBC support registers a service with this interface that
* collects all registered drivers and yet includes the drivers available via
* {@link java.sql.DriverManager}.
*
*
* Implementations of all interfaces in this package must be thread-safe.
*/
@org.osgi.annotation.versioning.Version("1.0.2")
package net.yetamine.osgi.jdbc;