http://www.eclipse.org/jgit//org.eclipse.jgit: Repository access and algorithms (Eclipse JGit Project)
  • Eclipse Distribution License (New BSD License)
  • Andrey Loskutov
  • Christian Halstrick
  • Dave Borowitz
  • David Pursehouse
  • Gunnar Wagenknecht
  • Jonathan Nieder
  • Jonathan Tan
  • Matthias Sohn
  • Sasa Zivkov
  • Terry Parker
  • Thomas Wolf 
/*
 * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
 * and other copyright owners as documented in the project's IP log.
 *
 * This program and the accompanying materials are made available
 * under the terms of the Eclipse Distribution License v1.0 which
 * accompanies this distribution, is reproduced below, and is
 * available at http://www.eclipse.org/org/documents/edl-v10.php
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or
 * without modification, are permitted provided that the following
 * conditions are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials provided
 *   with the distribution.
 *
 * - Neither the name of the Eclipse Foundation, Inc. nor the
 *   names of its contributors may be used to endorse or promote
 *   products derived from this software without specific prior
 *   written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.eclipse.jgit.treewalk.filter;

import java.io.IOException;

import org.eclipse.jgit.dircache.DirCacheIterator;
import org.eclipse.jgit.errors.IncorrectObjectTypeException;
import org.eclipse.jgit.errors.MissingObjectException;
import org.eclipse.jgit.treewalk.TreeWalk;
import org.eclipse.jgit.treewalk.WorkingTreeIterator;


Selects interesting tree entries during walking.


This is an abstract interface. Applications may implement a subclass, or use
one of the predefined implementations already available within this package.

 Unless specifically noted otherwise a TreeFilter implementation is not thread safe and may not be shared by different TreeWalk instances at the same time. This restriction allows TreeFilter implementations to cache state within their instances during include(TreeWalk) if it is beneficial to their implementation. Deep clones created by clone() may be used to construct a thread-safe copy of an existing filter. 

Path filters:




Difference filters:




Boolean modifiers:



/**
 * Selects interesting tree entries during walking.
 * <p>
 * This is an abstract interface. Applications may implement a subclass, or use
 * one of the predefined implementations already available within this package.
 * <p>
 * Unless specifically noted otherwise a TreeFilter implementation is not thread
 * safe and may not be shared by different TreeWalk instances at the same time.
 * This restriction allows TreeFilter implementations to cache state within
 * their instances during {@link #include(TreeWalk)} if it is beneficial to
 * their implementation. Deep clones created by {@link #clone()} may be used to
 * construct a thread-safe copy of an existing filter.
 *
 * <p>
 * <b>Path filters:</b>
 * <ul>
 * <li>Matching pathname:
 * {@link org.eclipse.jgit.treewalk.filter.PathFilter}</li>
 * </ul>
 *
 * <p>
 * <b>Difference filters:</b>
 * <ul>
 * <li>Only select differences: {@link #ANY_DIFF}.</li>
 * </ul>
 *
 * <p>
 * <b>Boolean modifiers:</b>
 * <ul>
 * <li>AND: {@link org.eclipse.jgit.treewalk.filter.AndTreeFilter}</li>
 * <li>OR: {@link org.eclipse.jgit.treewalk.filter.OrTreeFilter}</li>
 * <li>NOT: {@link org.eclipse.jgit.treewalk.filter.NotTreeFilter}</li>
 * </ul>
 */
public abstract class TreeFilter {
	
Selects all tree entries. 
/** Selects all tree entries. */
	public static final TreeFilter ALL = new AllFilter();

	private static final class AllFilter extends TreeFilter {
		@Override
		public boolean include(TreeWalk walker) {
			return true;
		}

		@Override
		public boolean shouldBeRecursive() {
			return false;
		}

		@Override
		public TreeFilter clone() {
			return this;
		}

		@Override
		public String toString() {
			return "ALL"; //$NON-NLS-1$
		}
	}

	
Selects only tree entries which differ between at least 2 trees.


This filter also prevents a TreeWalk from recursing into a subtree if all
parent trees have the identical subtree at the same path. This
dramatically improves walk performance as only the changed subtrees are
entered into.

 If this filter is applied to a walker with only one tree it behaves like ALL, or as though the walker was matching a virtual empty tree against the single tree it was actually given. Applications may wish to treat such a difference as "all names added". 
 When comparing WorkingTreeIterator and DirCacheIterator applications should use IndexDiffFilter. 
/**
	 * Selects only tree entries which differ between at least 2 trees.
	 * <p>
	 * This filter also prevents a TreeWalk from recursing into a subtree if all
	 * parent trees have the identical subtree at the same path. This
	 * dramatically improves walk performance as only the changed subtrees are
	 * entered into.
	 * <p>
	 * If this filter is applied to a walker with only one tree it behaves like
	 * {@link #ALL}, or as though the walker was matching a virtual empty tree
	 * against the single tree it was actually given. Applications may wish to
	 * treat such a difference as "all names added".
	 * <p>
	 * When comparing {@link WorkingTreeIterator} and {@link DirCacheIterator}
	 * applications should use {@link IndexDiffFilter}.
	 */
	public static final TreeFilter ANY_DIFF = new AnyDiffFilter();

	private static final class AnyDiffFilter extends TreeFilter {
		private static final int baseTree = 0;

		@Override
		public boolean include(TreeWalk walker) {
			final int n = walker.getTreeCount();
			if (n == 1) // Assume they meant difference to empty tree.
				return true;

			final int m = walker.getRawMode(baseTree);
			for (int i = 1; i < n; i++)
				if (walker.getRawMode(i) != m || !walker.idEqual(i, baseTree))
					return true;
			return false;
		}

		@Override
		public boolean shouldBeRecursive() {
			return false;
		}

		@Override
		public TreeFilter clone() {
			return this;
		}

		@Override
		public String toString() {
			return "ANY_DIFF"; //$NON-NLS-1$
		}
	}

	
Create a new filter that does the opposite of this filter.

Returns:a new filter that includes tree entries this filter rejects.
/**
	 * Create a new filter that does the opposite of this filter.
	 *
	 * @return a new filter that includes tree entries this filter rejects.
	 */
	public TreeFilter negate() {
		return NotTreeFilter.create(this);
	}

	
Determine if the current entry is interesting to report.

 This method is consulted for subtree entries even if TreeWalk.isRecursive() is enabled. The consultation allows the filter to bypass subtree recursion on a case-by-case basis, even when recursion is enabled at the application level. 
Params:
  • walker – 
           the walker the filter needs to examine.
Throws:
  • MissingObjectException – 
            an object the filter needs to consult to determine its answer
            does not exist in the Git repository the walker is operating
            on. Filtering this current walker entry is impossible without
            the object.
  • IncorrectObjectTypeException – 
            an object the filter needed to consult was not of the
            expected object type. This usually indicates a corrupt
            repository, as an object link is referencing the wrong type.
  • IOException – 
            a loose object or pack file could not be read to obtain data
            necessary for the filter to make its decision.
Returns:true if the current entry should be seen by the application;
        false to hide the entry.
/**
	 * Determine if the current entry is interesting to report.
	 * <p>
	 * This method is consulted for subtree entries even if
	 * {@link org.eclipse.jgit.treewalk.TreeWalk#isRecursive()} is enabled. The
	 * consultation allows the filter to bypass subtree recursion on a
	 * case-by-case basis, even when recursion is enabled at the application
	 * level.
	 *
	 * @param walker
	 *            the walker the filter needs to examine.
	 * @return true if the current entry should be seen by the application;
	 *         false to hide the entry.
	 * @throws org.eclipse.jgit.errors.MissingObjectException
	 *             an object the filter needs to consult to determine its answer
	 *             does not exist in the Git repository the walker is operating
	 *             on. Filtering this current walker entry is impossible without
	 *             the object.
	 * @throws org.eclipse.jgit.errors.IncorrectObjectTypeException
	 *             an object the filter needed to consult was not of the
	 *             expected object type. This usually indicates a corrupt
	 *             repository, as an object link is referencing the wrong type.
	 * @throws java.io.IOException
	 *             a loose object or pack file could not be read to obtain data
	 *             necessary for the filter to make its decision.
	 */
	public abstract boolean include(TreeWalk walker)
			throws MissingObjectException, IncorrectObjectTypeException,
			IOException;

	
Determine if the current entry is a parent, a match, or no match.

 This method extends the result returned by include(TreeWalk) with a third option (-1), splitting the value true. This gives the application a possibility to distinguish between an exact match and the case when a subtree to the current entry might be a match. 
Params:
  • walker – 
           the walker the filter needs to examine.
Throws:
Returns:-1 if the current entry is a parent of the filter but no exact
        match has been made; 0 if the current entry should be seen by the
        application; 1 if it should be hidden.
Since:4.7
/**
	 * Determine if the current entry is a parent, a match, or no match.
	 * <p>
	 * This method extends the result returned by {@link #include(TreeWalk)}
	 * with a third option (-1), splitting the value true. This gives the
	 * application a possibility to distinguish between an exact match and the
	 * case when a subtree to the current entry might be a match.
	 *
	 * @param walker
	 *            the walker the filter needs to examine.
	 * @return -1 if the current entry is a parent of the filter but no exact
	 *         match has been made; 0 if the current entry should be seen by the
	 *         application; 1 if it should be hidden.
	 * @throws org.eclipse.jgit.errors.MissingObjectException
	 *             as thrown by {@link #include(TreeWalk)}
	 * @throws org.eclipse.jgit.errors.IncorrectObjectTypeException
	 *             as thrown by {@link #include(TreeWalk)}
	 * @throws java.io.IOException
	 *             as thrown by {@link #include(TreeWalk)}
	 * @since 4.7
	 */
	public int matchFilter(TreeWalk walker)
			throws MissingObjectException, IncorrectObjectTypeException,
			IOException
	{
		return include(walker) ? 0 : 1;
	}

	
Does this tree filter require a recursive walk to match everything?


If this tree filter is matching on full entry path names and its pattern
is looking for a '/' then the filter would require a recursive TreeWalk
to accurately make its decisions. The walker is not required to enable
recursive behavior for any particular filter, this is only a hint.

Returns:true if the filter would like to have the walker recurse into
        subtrees to make sure it matches everything correctly; false if
        the filter does not require entering subtrees.
/**
	 * Does this tree filter require a recursive walk to match everything?
	 * <p>
	 * If this tree filter is matching on full entry path names and its pattern
	 * is looking for a '/' then the filter would require a recursive TreeWalk
	 * to accurately make its decisions. The walker is not required to enable
	 * recursive behavior for any particular filter, this is only a hint.
	 *
	 * @return true if the filter would like to have the walker recurse into
	 *         subtrees to make sure it matches everything correctly; false if
	 *         the filter does not require entering subtrees.
	 */
	public abstract boolean shouldBeRecursive();

	
{@inheritDoc}
Clone this tree filter, including its parameters.


This is a deep clone. If this filter embeds objects or other filters it
must also clone those, to ensure the instances do not share mutable data.

/**
	 * {@inheritDoc}
	 *
	 * Clone this tree filter, including its parameters.
	 * <p>
	 * This is a deep clone. If this filter embeds objects or other filters it
	 * must also clone those, to ensure the instances do not share mutable data.
	 */
	@Override
	public abstract TreeFilter clone();

	
{@inheritDoc} 
/** {@inheritDoc} */
	@Override
	public String toString() {
		String n = getClass().getName();
		int lastDot = n.lastIndexOf('.');
		if (lastDot >= 0) {
			n = n.substring(lastDot + 1);
		}
		return n.replace('$', '.');
	}
}