/*******************************************************************************
* Copyright (c) 2004, 2006 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.resources.mapping;
import java.util.ArrayList;
import org.eclipse.core.internal.resources.mapping.ModelProviderManager;
import org.eclipse.core.resources.*;
import org.eclipse.core.runtime.*;
/**
* A resource mapping supports the transformation of an application model object into its underlying
* file system resources. It provides the bridge between a logical element and the physical
* resource(s) into which it is stored but does not provide more comprehensive model access or
* manipulations.
* <p>
* Mappings provide two means of model traversal. The {@link #accept} method can be used to visit
* the resources that constitute the model object. Alternatively, a set or traversals can be
* obtained by calling {@link #getTraversals}. A traversal contains a set of resources and a depth.
* This allows clients (such a repository providers) to do optimal traversals of the resources
* w.r.t. the operation that is being performed on the model object.
* </p>
* <p>
* This class may be subclassed by clients.
* </p>
*
* @see IResource
* @see ResourceTraversal
* @since 3.2
*/
public abstract class ResourceMapping extends PlatformObject {
/**
* Accepts the given visitor for all existing resources in this mapping. The visitor's
* {@link IResourceVisitor#visit} method is called for each accessible resource in this mapping.
*
* @param context the traversal context
* @param visitor the visitor
* @param monitor a progress monitor, or <code>null</code> if progress reporting is not desired
* @exception CoreException if this method fails. Reasons include:
* <ul>
* <li>The visitor failed with this exception.</li>
* <li>The traversals for this mapping could not be obtained.</li>
* </ul>
*/
public void accept(ResourceMappingContext context, IResourceVisitor visitor, IProgressMonitor monitor) throws CoreException {
ResourceTraversal[] traversals= getTraversals(context, monitor);
for (int i= 0; i < traversals.length; i++)
traversals[i].accept(visitor);
}
/**
* Return whether this resource mapping contains all the resources of the given mapping.
* <p>
* This method always returns <code>false</code> when the given resource mapping's model
* provider id does not match that the of the receiver.
* </p>
*
* @param mapping the given resource mapping
* @return <code>true</code> if this mapping contains all the resources of the given mapping,
* and <code>false</code> otherwise.
*/
public boolean contains(ResourceMapping mapping) {
return false;
}
/**
* Override equals to compare the model objects of the mapping in order to determine equality.
*
* @param obj the object to compare
* @return <code>true</code> if the receiver is equal to the given object, and
* <code>false</code> otherwise.
*/
public boolean equals(Object obj) {
if (obj == this)
return true;
if (obj instanceof ResourceMapping) {
ResourceMapping other= (ResourceMapping)obj;
return other.getModelObject().equals(getModelObject());
}
return false;
}
/**
* Returns all markers of the specified type on the resources in this mapping. If
* <code>includeSubtypes</code> is <code>false</code>, only markers whose type exactly matches
* the given type are returned. Returns an empty array if there are no matching markers.
*
* @param type the type of marker to consider, or <code>null</code> to indicate all types
* @param includeSubtypes whether or not to consider sub-types of the given type
* @param monitor a progress monitor, or <code>null</code> if progress reporting is not desired
* @return an array of markers
* @exception CoreException if this method fails.
*/
public IMarker[] findMarkers(String type, boolean includeSubtypes, IProgressMonitor monitor) throws CoreException {
final ResourceTraversal[] traversals= getTraversals(ResourceMappingContext.LOCAL_CONTEXT, monitor);
ArrayList result= new ArrayList();
for (int i= 0; i < traversals.length; i++)
traversals[i].doFindMarkers(result, type, includeSubtypes);
return (IMarker[])result.toArray(new IMarker[result.size()]);
}
/**
* Returns the application model element associated with this resource mapping.
*
* @return the application model element associated with this resource mapping.
*/
public abstract Object getModelObject();
/**
* Return the model provider for the model object of this resource mapping. The model provider
* is obtained using the id returned from <code>getModelProviderId()</code>.
*
* @return the model provider
*/
public final ModelProvider getModelProvider() {
try {
return ModelProviderManager.getDefault().getModelProvider(getModelProviderId());
} catch (CoreException e) {
throw new IllegalStateException(e.getMessage());
}
}
/**
* Returns the id of the model provider that generated this resource mapping.
*
* @return the model provider id
*/
public abstract String getModelProviderId();
/**
* Returns the projects that contain the resources that constitute this application model.
*
* @return the projects
*/
public abstract IProject[] getProjects();
/**
* Returns one or more traversals that can be used to access all the physical resources that
* constitute the logical resource. A traversal is simply a set of resources and the depth to
* which they are to be traversed. This method returns an array of traversals in order to
* provide flexibility in describing the traversals that constitute a model element.
* <p>
* Subclasses should, when possible, include all resources that are or may be members of the
* model element. For instance, a model element should return the same list of resources
* regardless of the existence of the files on the file system. For example, if a logical
* resource called "form" maps to "/p1/form.xml" and "/p1/form.java" then whether form.xml or
* form.java existed, they should be returned by this method.
* </p>
* <p>
* In some cases, it may not be possible for a model element to know all the resources that may
* constitute the element without accessing the state of the model element in another location
* (e.g. a repository). This method is provided with a context which, when provided, gives
* access to the members of corresponding remote containers and the contents of corresponding
* remote files. This gives the model element the opportunity to deduce what additional
* resources should be included in the traversal.
* </p>
*
* @param context gives access to the state of remote resources that correspond to local
* resources for the purpose of determining traversals that adequately cover the
* model element resources given the state of the model element in another location.
* This parameter may be <code>null</code>, in which case the implementor can assume
* that only the local resources are of interest to the client.
* @param monitor a progress monitor, or <code>null</code> if progress reporting is not desired
* @return a set of traversals that cover the resources that constitute the model element
* @exception CoreException if the traversals could not be obtained.
*/
public abstract ResourceTraversal[] getTraversals(ResourceMappingContext context, IProgressMonitor monitor) throws CoreException;
/**
* Override hashCode to use the model object.
*/
public int hashCode() {
return getModelObject().hashCode();
}
}