IContainer.java

/*******************************************************************************
 *  Copyright (c) 2000, 2010 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
 *     Serge Beauchamp (Freescale Semiconductor) - [252996] add addFilter/removeFilter/getFilters
 *******************************************************************************/
package org.eclipse.core.resources;

import org.eclipse.core.filesystem.IFileInfo;
import org.eclipse.core.runtime.*;

/**
 * Interface for resources which may contain other resources (termed its <em>members</em>). While
 * the workspace itself is not considered a container in this sense, the workspace root resource is
 * a container.
 * <p>
 * Containers implement the <code>IAdaptable</code> interface; extensions are managed by the
 * platform's adapter manager.
 * </p>
 * 
 * @see Platform#getAdapterManager()
 * @see IProject
 * @see IFolder
 * @see IWorkspaceRoot
 * @noimplement This interface is not intended to be implemented by clients.
 * @noextend This interface is not intended to be extended by clients.
 */
public interface IContainer extends IResource, IAdaptable {

	/*====================================================================
	 * Constants defining which members are wanted:
	 *====================================================================*/

	/**
	 * Member constant (bit mask value 1) indicating that phantom member resources are to be
	 * included.
	 * 
	 * @see IResource#isPhantom()
	 * @since 2.0
	 */
	public static final int INCLUDE_PHANTOMS= 1;

	/**
	 * Member constant (bit mask value 2) indicating that team private members are to be included.
	 * 
	 * @see IResource#isTeamPrivateMember()
	 * @since 2.0
	 */
	public static final int INCLUDE_TEAM_PRIVATE_MEMBERS= 2;

	/**
	 * Member constant (bit mask value 4) indicating that derived resources are to be excluded.
	 * 
	 * @see IResource#isDerived()
	 * @since 3.1
	 */
	public static final int EXCLUDE_DERIVED= 4;

	/**
	 * Member constant (bit mask value 8) indicating that hidden resources are to be included.
	 * 
	 * @see IResource#isHidden()
	 * @since 3.4
	 */
	public static final int INCLUDE_HIDDEN= 8;

	/**
	 * Returns whether a resource of some type with the given path exists relative to this resource.
	 * The supplied path may be absolute or relative; in either case, it is interpreted as relative
	 * to this resource. Trailing separators are ignored. If the path is empty this container is
	 * checked for existence.
	 * 
	 * @param path the path of the resource
	 * @return <code>true</code> if a resource of some type with the given path exists relative to
	 *         this resource, and <code>false</code> otherwise
	 * @see IResource#exists()
	 */
	public boolean exists(IPath path);

	/**
	 * Finds and returns the member resource (project, folder, or file) with the given name in this
	 * container, or <code>null</code> if no such resource exists.
	 * 
	 * <p>
	 * N.B. Unlike the methods which traffic strictly in resource handles, this method infers the
	 * resulting resource's type from the resource existing at the calculated path in the workspace.
	 * </p>
	 * 
	 * @param name the string name of the member resource
	 * @return the member resource, or <code>null</code> if no such resource exists
	 */
	public IResource findMember(String name);

	/**
	 * Finds and returns the member resource (project, folder, or file) with the given name in this
	 * container, or <code>null</code> if there is no such resource.
	 * <p>
	 * If the <code>includePhantoms</code> argument is <code>false</code>, only a member resource
	 * with the given name that exists will be returned. If the <code>includePhantoms</code>
	 * argument is <code>true</code>, the method also returns a resource if the workspace is keeping
	 * track of a phantom with that name.
	 * </p>
	 * <p>
	 * Note that no attempt is made to exclude team-private member resources as with
	 * <code>members</code>.
	 * </p>
	 * <p>
	 * N.B. Unlike the methods which traffic strictly in resource handles, this method infers the
	 * resulting resource's type from the existing resource (or phantom) in the workspace.
	 * </p>
	 * 
	 * @param name the string name of the member resource
	 * @param includePhantoms <code>true</code> if phantom resources are of interest;
	 *            <code>false</code> if phantom resources are not of interest
	 * @return the member resource, or <code>null</code> if no such resource exists
	 * @see #members()
	 * @see IResource#isPhantom()
	 */
	public IResource findMember(String name, boolean includePhantoms);

	/**
	 * Finds and returns the member resource identified by the given path in this container, or
	 * <code>null</code> if no such resource exists. The supplied path may be absolute or relative;
	 * in either case, it is interpreted as relative to this resource. Trailing separators and the
	 * path's device are ignored. If the path is empty this container is returned. Parent references
	 * in the supplied path are discarded if they go above the workspace root.
	 * <p>
	 * Note that no attempt is made to exclude team-private member resources as with
	 * <code>members</code>.
	 * </p>
	 * <p>
	 * N.B. Unlike the methods which traffic strictly in resource handles, this method infers the
	 * resulting resource's type from the resource existing at the calculated path in the workspace.
	 * </p>
	 * 
	 * @param path the path of the desired resource
	 * @return the member resource, or <code>null</code> if no such resource exists
	 */
	public IResource findMember(IPath path);

	/**
	 * Finds and returns the member resource identified by the given path in this container, or
	 * <code>null</code> if there is no such resource. The supplied path may be absolute or
	 * relative; in either case, it is interpreted as relative to this resource. Trailing separators
	 * and the path's device are ignored. If the path is empty this container is returned. Parent
	 * references in the supplied path are discarded if they go above the workspace root.
	 * <p>
	 * If the <code>includePhantoms</code> argument is <code>false</code>, only a resource that
	 * exists at the given path will be returned. If the <code>includePhantoms</code> argument is
	 * <code>true</code>, the method also returns a resource if the workspace is keeping track of a
	 * phantom member resource at the given path.
	 * </p>
	 * <p>
	 * Note that no attempt is made to exclude team-private member resources as with
	 * <code>members</code>.
	 * </p>
	 * <p>
	 * N.B. Unlike the methods which traffic strictly in resource handles, this method infers the
	 * resulting resource's type from the existing resource (or phantom) at the calculated path in
	 * the workspace.
	 * </p>
	 * 
	 * @param path the path of the desired resource
	 * @param includePhantoms <code>true</code> if phantom resources are of interest;
	 *            <code>false</code> if phantom resources are not of interest
	 * @return the member resource, or <code>null</code> if no such resource exists
	 * @see #members(boolean)
	 * @see IResource#isPhantom()
	 */
	public IResource findMember(IPath path, boolean includePhantoms);

	/**
	 * Returns the default charset for resources in this container.
	 * <p>
	 * This is a convenience method, fully equivalent to:
	 * 
	 * <pre>
	 * getDefaultCharset(true);
	 * </pre>
	 * 
	 * </p>
	 * <p>
	 * Note that this method does not check whether the result is a supported charset name. Callers
	 * should be prepared to handle <code>UnsupportedEncodingException</code> where this charset is
	 * used.
	 * </p>
	 * 
	 * @return the name of the default charset encoding for this container
	 * @exception CoreException if this method fails
	 * @see IContainer#getDefaultCharset(boolean)
	 * @see IFile#getCharset()
	 * @since 3.0
	 */
	public String getDefaultCharset() throws CoreException;

	/**
	 * Returns the default charset for resources in this container.
	 * <p>
	 * If checkImplicit is <code>false</code>, this method will return the charset defined by
	 * calling #setDefaultCharset, provided this container exists, or <code>null</code> otherwise.
	 * </p>
	 * <p>
	 * If checkImplicit is <code>true</code>, this method uses the following algorithm to determine
	 * the charset to be returned:
	 * <ol>
	 * <li>the one explicitly set by calling #setDefaultCharset (with a non-null argument) on this
	 * container, if any, and this container exists, or</li>
	 * <li>the parent's default charset, if this container has a parent (is not the workspace root),
	 * or</li>
	 * <li>the charset returned by ResourcesPlugin#getEncoding.</li>
	 * </ol>
	 * </p>
	 * <p>
	 * Note that this method does not check whether the result is a supported charset name. Callers
	 * should be prepared to handle <code>UnsupportedEncodingException</code> where this charset is
	 * used.
	 * </p>
	 * 
	 * @return the name of the default charset encoding for this container, or <code>null</code>
	 * @exception CoreException if this method fails
	 * @see IFile#getCharset()
	 * @since 3.0
	 */
	public String getDefaultCharset(boolean checkImplicit) throws CoreException;

	/**
	 * Returns a handle to the file identified by the given path in this container.
	 * <p>
	 * This is a resource handle operation; neither the resource nor the result need exist in the
	 * workspace. The validation check on the resource name/path is not done when the resource
	 * handle is constructed; rather, it is done automatically as the resource is created.
	 * <p>
	 * The supplied path may be absolute or relative; in either case, it is interpreted as relative
	 * to this resource and is appended to this container's full path to form the full path of the
	 * resultant resource. A trailing separator is ignored. The path of the resulting resource must
	 * have at least two segments.
	 * </p>
	 * 
	 * @param path the path of the member file
	 * @return the (handle of the) member file
	 * @see #getFolder(IPath)
	 */
	public IFile getFile(IPath path);

	/**
	 * Returns a handle to the folder identified by the given path in this container.
	 * <p>
	 * This is a resource handle operation; neither the resource nor the result need exist in the
	 * workspace. The validation check on the resource name/path is not done when the resource
	 * handle is constructed; rather, it is done automatically as the resource is created.
	 * <p>
	 * The supplied path may be absolute or relative; in either case, it is interpreted as relative
	 * to this resource and is appended to this container's full path to form the full path of the
	 * resultant resource. A trailing separator is ignored. The path of the resulting resource must
	 * have at least two segments.
	 * </p>
	 * 
	 * @param path the path of the member folder
	 * @return the (handle of the) member folder
	 * @see #getFile(IPath)
	 */
	public IFolder getFolder(IPath path);

	/**
	 * Returns a list of existing member resources (projects, folders and files) in this resource,
	 * in no particular order.
	 * <p>
	 * This is a convenience method, fully equivalent to <code>members(IResource.NONE)</code>.
	 * Team-private member resources are <b>not</b> included in the result.
	 * </p>
	 * <p>
	 * Note that the members of a project or folder are the files and folders immediately contained
	 * within it. The members of the workspace root are the projects in the workspace.
	 * </p>
	 * 
	 * @return an array of members of this resource
	 * @exception CoreException if this request fails. Reasons include:
	 *                <ul>
	 *                <li>This resource does not exist.</li>
	 *                <li>This resource is a project that is not open.</li>
	 *                </ul>
	 * @see #findMember(IPath)
	 * @see IResource#isAccessible()
	 */
	public IResource[] members() throws CoreException;

	/**
	 * Returns a list of all member resources (projects, folders and files) in this resource, in no
	 * particular order.
	 * <p>
	 * This is a convenience method, fully equivalent to:
	 * 
	 * <pre>
	 * members(includePhantoms ? INCLUDE_PHANTOMS : IResource.NONE);
	 * </pre>
	 * 
	 * Team-private member resources are <b>not</b> included in the result.
	 * </p>
	 * 
	 * @param includePhantoms <code>true</code> if phantom resources are of interest;
	 *            <code>false</code> if phantom resources are not of interest
	 * @return an array of members of this resource
	 * @exception CoreException if this request fails. Reasons include:
	 *                <ul>
	 *                <li>This resource does not exist.</li>
	 *                <li> <code>includePhantoms</code> is <code>false</code> and this resource does
	 *                not exist.</li>
	 *                <li> <code>includePhantoms</code> is <code>false</code> and this resource is a
	 *                project that is not open.</li>
	 *                </ul>
	 * @see #members(int)
	 * @see IResource#exists()
	 * @see IResource#isPhantom()
	 */
	public IResource[] members(boolean includePhantoms) throws CoreException;

	/**
	 * Returns a list of all member resources (projects, folders and files) in this resource, in no
	 * particular order.
	 * <p>
	 * If the <code>INCLUDE_PHANTOMS</code> flag is not specified in the member flags (recommended),
	 * only member resources that exist will be returned. If the <code>INCLUDE_PHANTOMS</code> flag
	 * is specified, the result will also include any phantom member resources the workspace is
	 * keeping track of.
	 * </p>
	 * <p>
	 * If the <code>INCLUDE_TEAM_PRIVATE_MEMBERS</code> flag is specified in the member flags, team
	 * private members will be included along with the others. If the
	 * <code>INCLUDE_TEAM_PRIVATE_MEMBERS</code> flag is not specified (recommended), the result
	 * will omit any team private member resources.
	 * </p>
	 * <p>
	 * If the {@link #INCLUDE_HIDDEN} flag is specified in the member flags, hidden members will be
	 * included along with the others. If the {@link #INCLUDE_HIDDEN} flag is not specified
	 * (recommended), the result will omit any hidden member resources.
	 * </p>
	 * <p>
	 * If the <code>EXCLUDE_DERIVED</code> flag is not specified, derived resources are included. If
	 * the <code>EXCLUDE_DERIVED</code> flag is specified in the member flags, derived resources are
	 * not included.
	 * </p>
	 * 
	 * @param memberFlags bit-wise or of member flag constants ({@link #INCLUDE_PHANTOMS},
	 *            {@link #INCLUDE_TEAM_PRIVATE_MEMBERS}, {@link #INCLUDE_HIDDEN} and
	 *            {@link #EXCLUDE_DERIVED}) indicating which members are of interest
	 * @return an array of members of this resource
	 * @exception CoreException if this request fails. Reasons include:
	 *                <ul>
	 *                <li>This resource does not exist.</li>
	 *                <li>the <code>INCLUDE_PHANTOMS</code> flag is not specified and this resource
	 *                does not exist.</li>
	 *                <li>the <code>INCLUDE_PHANTOMS</code> flag is not specified and this resource
	 *                is a project that is not open.</li>
	 *                </ul>
	 * @see IResource#exists()
	 * @since 2.0
	 */
	public IResource[] members(int memberFlags) throws CoreException;

	/**
	 * Returns a list of recently deleted files inside this container that have one or more saved
	 * states in the local history. The depth parameter determines how deep inside the container to
	 * look. This resource may or may not exist in the workspace.
	 * <p>
	 * When applied to an existing project resource, this method returns recently deleted files with
	 * saved states in that project. Note that local history is maintained with each individual
	 * project, and gets discarded when a project is deleted from the workspace. If applied to a
	 * deleted project, this method returns the empty list.
	 * </p>
	 * <p>
	 * When applied to the workspace root resource (depth infinity), this method returns all
	 * recently deleted files with saved states in all existing projects.
	 * </p>
	 * <p>
	 * When applied to a folder (or project) resource (depth one), this method returns all recently
	 * deleted member files with saved states.
	 * </p>
	 * <p>
	 * When applied to a folder resource (depth zero), this method returns an empty list unless
	 * there was a recently deleted file with saved states at the same path as the folder.
	 * </p>
	 * <p>
	 * This method is long-running; progress and cancellation are provided by the given progress
	 * monitor.
	 * </p>
	 * 
	 * @param depth depth limit: one of <code>DEPTH_ZERO</code>, <code>DEPTH_ONE</code> or
	 *            <code>DEPTH_INFINITE</code>
	 * @param monitor a progress monitor, or <code>null</code> if progress reporting and
	 *            cancellation are not desired
	 * @return an array of recently deleted files
	 * @exception CoreException if this method fails
	 * @see IFile#getHistory(IProgressMonitor)
	 * @since 2.0
	 */
	public IFile[] findDeletedMembersWithHistory(int depth, IProgressMonitor monitor) throws CoreException;

	/**
	 * Sets the default charset for this container. Passing a value of <code>null</code> will remove
	 * the default charset setting for this resource.
	 * 
	 * @param charset a charset string, or <code>null</code>
	 * @exception CoreException if this method fails Reasons include:
	 *                <ul>
	 *                <li>This resource does not exist.</li>
	 *                <li>An error happened while persisting this setting.</li>
	 *                </ul>
	 * @see IContainer#getDefaultCharset()
	 * @since 3.0
	 * @deprecated Replaced by {@link #setDefaultCharset(String, IProgressMonitor)} which is a
	 *             workspace operation and reports changes in resource deltas.
	 */
	public void setDefaultCharset(String charset) throws CoreException;

	/**
	 * Sets the default charset for this container. Passing a value of <code>null</code> will remove
	 * the default charset setting for this resource.
	 * <p>
	 * This method changes resources; these changes will be reported in a subsequent resource change
	 * event, including an indication that the encoding of affected resources has been changed.
	 * </p>
	 * <p>
	 * This method is long-running; progress and cancellation are provided by the given progress
	 * monitor.
	 * </p>
	 * 
	 * @param charset a charset string, or <code>null</code>
	 * @param monitor a progress monitor, or <code>null</code> if progress reporting is not desired
	 * @exception OperationCanceledException if the operation is canceled. Cancelation can occur
	 *                even if no progress monitor is provided.
	 * @exception CoreException if this method fails Reasons include:
	 *                <ul>
	 *                <li>This resource is not accessible.</li>
	 *                <li>An error happened while persisting this setting.</li>
	 *                <li>Resource changes are disallowed during certain types of resource change
	 *                event notification. See {@link IResourceChangeEvent} for more details.</li>
	 *                </ul>
	 * @see IContainer#getDefaultCharset()
	 * @see IResourceRuleFactory#charsetRule(IResource)
	 * @since 3.0
	 */
	public void setDefaultCharset(String charset, IProgressMonitor monitor) throws CoreException;

	/**
	 * Adds a new filter to this container. Filters restrict the set of files and directories in the
	 * underlying file system that will be included as members of this container.
	 * <p>
	 * The {@link IResource#BACKGROUND_REFRESH} update flag controls when changes to the resource
	 * hierarchy under this container resulting from the new filter take effect. If this flag is
	 * specified, the resource hierarchy is updated in a separate thread after this method returns.
	 * If the flag is not specified, any resource changes resulting from the new filter will occur
	 * before this method returns.
	 * </p>
	 * <p>
	 * This operation changes resources; these changes will be reported in a subsequent resource
	 * change event that will include an indication of any resources that have been removed as a
	 * result of the new filter.
	 * </p>
	 * <p>
	 * This operation is long-running; progress and cancellation are provided by the given progress
	 * monitor.
	 * </p>
	 * 
	 * @param type ({@link IResourceFilterDescription#INCLUDE_ONLY} or
	 *            {@link IResourceFilterDescription#EXCLUDE_ALL} and/or
	 *            {@link IResourceFilterDescription#INHERITABLE})
	 * @param matcherDescription the description of the matcher that will determine which
	 *            {@link IFileInfo} instances will be excluded from the resource tree
	 * @param updateFlags bit-wise or of update flag constants ({@link IResource#BACKGROUND_REFRESH}
	 *            )
	 * @param monitor a progress monitor, or <code>null</code> if progress reporting is not desired
	 * @return the description of the added filter
	 * @exception CoreException if this filter could not be added. Reasons include:
	 *                <ul>
	 *                <li>Resource changes are disallowed during certain types of resource change
	 *                event notification. See <code>IResourceChangeEvent</code> for more details.</li>
	 *                </ul>
	 * @exception OperationCanceledException if the operation is canceled. Cancelation can occur
	 *                even if no progress monitor is provided.
	 * @see #getFilters()
	 * @see IResourceFilterDescription#delete(int, IProgressMonitor)
	 * 
	 * @since 3.6
	 */
	public IResourceFilterDescription createFilter(int type, FileInfoMatcherDescription matcherDescription, int updateFlags, IProgressMonitor monitor) throws CoreException;

	/**
	 * Retrieve all filters on this container. If no filters exist for this resource, an empty array
	 * is returned.
	 * 
	 * @return an array of filters
	 * @exception CoreException if this resource's filters could not be retrieved. Reasons include:
	 *                <ul>
	 *                <li>This resource is not a folder.</li>
	 * 
	 * @see #createFilter(int, FileInfoMatcherDescription, int, IProgressMonitor)
	 * @see IResourceFilterDescription#delete(int, IProgressMonitor)
	 * @since 3.6
	 */
	public IResourceFilterDescription[] getFilters() throws CoreException;
}