org.osgi.service.cm.Configuration Maven / Gradle / Ivy
/*
* Copyright (c) OSGi Alliance (2001, 2013). All Rights Reserved.
*
* 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.
*/
package org.osgi.service.cm;
import java.io.IOException;
import java.util.Dictionary;
import org.osgi.framework.Filter;
/**
* The configuration information for a {@code ManagedService} or
* {@code ManagedServiceFactory} object.
*
* The Configuration Admin service uses this interface to represent the
* configuration information for a {@code ManagedService} or for a service
* instance of a {@code ManagedServiceFactory}.
*
*
* A {@code Configuration} object contains a configuration dictionary and allows
* the properties to be updated via this object. Bundles wishing to receive
* configuration dictionaries do not need to use this class - they register a
* {@code ManagedService} or {@code ManagedServiceFactory}. Only administrative
* bundles, and bundles wishing to update their own configurations need to use
* this class.
*
*
* The properties handled in this configuration have case insensitive
* {@code String} objects as keys. However, case must be preserved from the last
* set key/value.
*
* A configuration can be bound to a specific bundle or to a region of
* bundles using the location. In its simplest form the location is the
* location of the target bundle that registered a Managed Service or a Managed
* Service Factory. However, if the location starts with {@code ?} then the
* location indicates multiple delivery. In such a case the configuration must
* be delivered to all targets.
*
* If security is on, the Configuration Permission can be used to restrict the
* targets that receive updates. The Configuration Admin must only update a
* target when the configuration location matches the location of the target's
* bundle or the target bundle has a Configuration Permission with the action
* {@link ConfigurationPermission#TARGET} and a name that matches the
* configuration location. The name in the permission may contain wildcards (
* {@code '*'}) to match the location using the same substring matching rules as
* {@link Filter}.
*
* Bundles can always create, manipulate, and be updated from configurations
* that have a location that matches their bundle location.
*
*
* If a configuration's location is {@code null}, it is not yet bound to a
* location. It will become bound to the location of the first bundle that
* registers a {@code ManagedService} or {@code ManagedServiceFactory} object
* with the corresponding PID.
*
* The same {@code Configuration} object is used for configuring both a Managed
* Service Factory and a Managed Service. When it is important to differentiate
* between these two the term "factory configuration" is used.
*
* @noimplement
* @author $Id: bc83a488c091cf0fbeb90e2c013f637bc82f2a26 $
*/
public interface Configuration {
/**
* Get the PID for this {@code Configuration} object.
*
* @return the PID for this {@code Configuration} object.
* @throws IllegalStateException if this configuration has been deleted
*/
public String getPid();
/**
* Return the properties of this {@code Configuration} object.
*
* The {@code Dictionary} object returned is a private copy for the caller
* and may be changed without influencing the stored configuration. The keys
* in the returned dictionary are case insensitive and are always of type
* {@code String}.
*
*
* If called just after the configuration is created and before update has
* been called, this method returns {@code null}.
*
* @return A private copy of the properties for the caller or {@code null}.
* These properties must not contain the "service.bundleLocation"
* property. The value of this property may be obtained from the
* {@link #getBundleLocation()} method.
* @throws IllegalStateException If this configuration has been deleted.
*/
public Dictionary getProperties();
/**
* Update the properties of this {@code Configuration} object.
*
* Stores the properties in persistent storage after adding or overwriting
* the following properties:
*
* - "service.pid" : is set to be the PID of this configuration.
* - "service.factoryPid" : if this is a factory configuration it is set
* to the factory PID else it is not set.
*
* These system properties are all of type {@code String}.
*
*
* If the corresponding Managed Service/Managed Service Factory is
* registered, its updated method must be called asynchronously. Else, this
* callback is delayed until aforementioned registration occurs.
*
*
* Also initiates an asynchronous call to all {@link ConfigurationListener}s
* with a {@link ConfigurationEvent#CM_UPDATED} event.
*
* @param properties the new set of properties for this configuration
* @throws IOException if update cannot be made persistent
* @throws IllegalArgumentException if the {@code Dictionary} object
* contains invalid configuration types or contains case variants of
* the same key name.
* @throws IllegalStateException If this configuration has been deleted.
*/
public void update(Dictionary properties) throws IOException;
/**
* Delete this {@code Configuration} object.
*
* Removes this configuration object from the persistent store. Notify
* asynchronously the corresponding Managed Service or Managed Service
* Factory. A {@link ManagedService} object is notified by a call to its
* {@code updated} method with a {@code null} properties argument. A
* {@link ManagedServiceFactory} object is notified by a call to its
* {@code deleted} method.
*
*
* Also initiates an asynchronous call to all {@link ConfigurationListener}s
* with a {@link ConfigurationEvent#CM_DELETED} event.
*
* @throws IOException If delete fails.
* @throws IllegalStateException If this configuration has been deleted.
*/
public void delete() throws IOException;
/**
* For a factory configuration return the PID of the corresponding Managed
* Service Factory, else return {@code null}.
*
* @return factory PID or {@code null}
* @throws IllegalStateException If this configuration has been deleted.
*/
public String getFactoryPid();
/**
* Update the {@code Configuration} object with the current properties.
*
* Initiate the {@code updated} callback to the Managed Service or Managed
* Service Factory with the current properties asynchronously.
*
*
* This is the only way for a bundle that uses a Configuration Plugin
* service to initiate a callback. For example, when that bundle detects a
* change that requires an update of the Managed Service or Managed Service
* Factory via its {@code ConfigurationPlugin} object.
*
* @see ConfigurationPlugin
* @throws IOException if update cannot access the properties in persistent
* storage
* @throws IllegalStateException If this configuration has been deleted.
*/
public void update() throws IOException;
/**
* Bind this {@code Configuration} object to the specified location.
*
* If the location parameter is {@code null} then the {@code Configuration}
* object will not be bound to a location/region. It will be set to the
* bundle's location before the first time a Managed Service/Managed Service
* Factory receives this {@code Configuration} object via the updated method
* and before any plugins are called. The bundle location or region will be
* set persistently.
*
*
* If the location starts with {@code ?} then all targets registered with
* the given PID must be updated.
*
*
* If the location is changed then existing targets must be informed. If
* they can no longer see this configuration, the configuration must be
* deleted or updated with {@code null}. If this configuration becomes
* visible then they must be updated with this configuration.
*
*
* Also initiates an asynchronous call to all {@link ConfigurationListener}s
* with a {@link ConfigurationEvent#CM_LOCATION_CHANGED} event.
*
* @param location a location, region, or {@code null}
* @throws IllegalStateException If this configuration has been deleted.
* @throws SecurityException when the required permissions are not available
* @throws SecurityException when the required permissions are not available
* @security ConfigurationPermission[this.location,CONFIGURE] if
* this.location is not {@code null}
* @security ConfigurationPermission[location,CONFIGURE] if location is not
* {@code null}
* @security ConfigurationPermission["*",CONFIGURE] if this.location is
* {@code null} or if location is {@code null}
*/
public void setBundleLocation(String location);
/**
* Get the bundle location.
*
* Returns the bundle location or region to which this configuration is
* bound, or {@code null} if it is not yet bound to a bundle location or
* region. If the location starts with {@code ?} then the configuration is
* delivered to all targets and not restricted to a single bundle.
*
* @return location to which this configuration is bound, or {@code null}.
* @throws IllegalStateException If this configuration has been deleted.
* @throws SecurityException when the required permissions are not available
* @security ConfigurationPermission[this.location,CONFIGURE] if
* this.location is not {@code null}
* @security ConfigurationPermission["*",CONFIGURE] if this.location is
* {@code null}
*
*/
public String getBundleLocation();
/**
* Get the change count.
*
* The Configuration must maintain a change counter that every time when
* this configuration is updated and its properties are stored is
* incremented with a positive value. The counter must be changed after the
* properties are persisted but before the targets are updated and events
* are sent out.
*
* @return A monotonously increasing value reflecting changes in this
* Configuration
*
* @since 1.5
*/
public long getChangeCount();
/**
* Equality is defined to have equal PIDs
*
* Two Configuration objects are equal when their PIDs are equal.
*
* @param other {@code Configuration} object to compare against
* @return {@code true} if equal, {@code false} if not a
* {@code Configuration} object or one with a different PID.
*/
public boolean equals(Object other);
/**
* Hash code is based on PID.
*
* The hash code for two Configuration objects must be the same when the
* Configuration PID's are the same.
*
* @return hash code for this Configuration object
*/
public int hashCode();
}