/*******************************************************************************
* Copyright (c) 2005 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.core.runtime.preferences;
import java.util.Map;
/**
* Preference filters are used to describe the relationship between the
* preference tree and a data set when importing/exporting preferences.
* <p>
* For instance, a client is able to create a preference filter describing which
* preference nodes/keys should be used when exporting the "Key Bindings"
* preferences. When the export happens, the tree is trimmed and only the
* applicable preferences will be exported.
* </p>
* <p>
* Clients may implement this interface.
* </p>
*
* @since 3.1
*/
public interface IPreferenceFilter {
/**
* Return an array of scopes that this preference filter is applicable for.
* The list of scopes must not be <code>null</code>.
* <p>
* For example:
* <code>new String[] {InstanceScope.SCOPE, ConfigurationScope.SCOPE};</code>
* </p>
*
* @return the array of scopes
*/
public String[] getScopes();
/**
* Return a mapping which defines the nodes and keys that this filter
* applies to.
* <p>
* If the map is <code>null</code> then this filter is applicable for all
* nodes within the scope. The map can also be <code>null</code> if the
* given scope is not known to this filter.
* </p>
* <p>
* The keys in the table are Strings and describe the node path. The values
* are an optional array of {@link PreferenceFilterEntry} objects describing
* the list of applicable keys in that node. If the value is null then the
* whole node is considered applicable.
* </p>
* <p>
* key: <code>String</code> (node)<br>
* value: <code>PreferenceFilterEntry[]</code> or <code>null</code>
* (preference keys)<br>
* </p>
* <p>
* For example:
*
* <pre>
* "org.eclipse.core.resources" -> null
* "org.eclipse.ui" -> new PreferenceFilterEntry[] {
* new PreferenceFilterEntry("DEFAULT_PERSPECTIVE_LOCATION"),
* new PreferenceFilterEntry("SHOW_INTRO_ON_STARTUP")}
* </pre>
*
* </p>
*
* @return the mapping table
* @see PreferenceFilterEntry
*/
public Map getMapping(String scope);
}