org.eclipse.jgit/src/org/eclipse/jgit/treewalk/filter/PathFilterGroup.java - jgit - Git at Google

 /*
  * Copyright (C) 2007, Robin Rosenberg <robin.rosenberg@dewire.com>
  * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org> and others
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Distribution License v. 1.0 which is available at
  * https://www.eclipse.org/org/documents/edl-v10.php.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */

 package org.eclipse.jgit.treewalk.filter;

 import java.util.Collection;

 import org.eclipse.jgit.errors.StopWalkException;
 import org.eclipse.jgit.internal.JGitText;
 import org.eclipse.jgit.treewalk.TreeWalk;
 import org.eclipse.jgit.treewalk.filter.ByteArraySet.Hasher;
 import org.eclipse.jgit.util.RawParseUtils;

 /**
  * Includes tree entries only if they match one or more configured paths.
  * <p>
  * Operates like {@link org.eclipse.jgit.treewalk.filter.PathFilter} but causes
  * the walk to abort as soon as the tree can no longer match any of the paths
  * within the group. This may bypass the boolean logic of a higher level AND or
  * OR group, but does improve performance for the common case of examining one
  * or more modified paths.
  * <p>
  * This filter is effectively an OR group around paths, with the early abort
  * feature described above.
  */
 public class PathFilterGroup {
 	/**
 	 * Create a collection of path filters from Java strings.
 	 * <p>
 	 * Path strings are relative to the root of the repository. If the user's
 	 * input should be assumed relative to a subdirectory of the repository the
 	 * caller must prepend the subdirectory's path prior to creating the filter.
 	 * <p>
 	 * Path strings use '/' to delimit directories on all platforms.
 	 * <p>
 	 * Paths may appear in any order within the collection. Sorting may be done
 	 * internally when the group is constructed if doing so will improve path
 	 * matching performance.
 	 *
 	 * @param paths
 	 *            the paths to test against. Must have at least one entry.
 	 * @return a new filter for the list of paths supplied.
 	 */
 	public static TreeFilter createFromStrings(Collection<String> paths) {
 		if (paths.isEmpty())
 			throw new IllegalArgumentException(
 					JGitText.get().atLeastOnePathIsRequired);
 		final PathFilter[] p = new PathFilter[paths.size()];
 		int i = 0;
 		for (String s : paths)
 			p[i++] = PathFilter.create(s);
 		return create(p);
 	}

 	/**
 	 * Create a collection of path filters from Java strings.
 	 * <p>
 	 * Path strings are relative to the root of the repository. If the user's
 	 * input should be assumed relative to a subdirectory of the repository the
 	 * caller must prepend the subdirectory's path prior to creating the filter.
 	 * <p>
 	 * Path strings use '/' to delimit directories on all platforms.
 	 * <p>
 	 * Paths may appear in any order. Sorting may be done internally when the
 	 * group is constructed if doing so will improve path matching performance.
 	 *
 	 * @param paths
 	 *            the paths to test against. Must have at least one entry.
 	 * @return a new filter for the paths supplied.
 	 */
 	public static TreeFilter createFromStrings(String... paths) {
 		if (paths.length == 0)
 			throw new IllegalArgumentException(
 					JGitText.get().atLeastOnePathIsRequired);
 		final int length = paths.length;
 		final PathFilter[] p = new PathFilter[length];
 		for (int i = 0; i < length; i++)
 			p[i] = PathFilter.create(paths[i]);
 		return create(p);
 	}

 	/**
 	 * Create a collection of path filters.
 	 * <p>
 	 * Paths may appear in any order within the collection. Sorting may be done
 	 * internally when the group is constructed if doing so will improve path
 	 * matching performance.
 	 *
 	 * @param paths
 	 *            the paths to test against. Must have at least one entry.
 	 * @return a new filter for the list of paths supplied.
 	 */
 	public static TreeFilter create(Collection<PathFilter> paths) {
 		if (paths.isEmpty())
 			throw new IllegalArgumentException(
 					JGitText.get().atLeastOnePathIsRequired);
 		final PathFilter[] p = new PathFilter[paths.size()];
 		paths.toArray(p);
 		return create(p);
 	}

 	private static TreeFilter create(PathFilter[] p) {
 		if (p.length == 1)
 			return new Single(p[0]);
 		return new Group(p);
 	}

 	static class Single extends TreeFilter {
 		private final PathFilter path;

 		private final byte[] raw;

 		private Single(PathFilter p) {
 			path = p;
 			raw = path.pathRaw;
 		}

 		@Override
 		public boolean include(TreeWalk walker) {
 			final int cmp = walker.isPathPrefix(raw, raw.length);
 			if (cmp > 0)
 				throw StopWalkException.INSTANCE;
 			return cmp == 0;
 		}

 		@Override
 		public boolean shouldBeRecursive() {
 			return path.shouldBeRecursive();
 		}

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

 		@Override
 		public String toString() {
 			return "FAST_" + path.toString(); //$NON-NLS-1$
 		}
 	}

 	static class Group extends TreeFilter {

 		private ByteArraySet fullpaths;

 		private ByteArraySet prefixes;

 		private byte[] max;

 		private Group(PathFilter[] pathFilters) {
 			fullpaths = new ByteArraySet(pathFilters.length);
 			prefixes = new ByteArraySet(pathFilters.length / 5);
 			// 5 is an empirically derived ratio of #paths/#prefixes from:
 			// egit/jgit: 8
 			// git: 5
 			// linux kernel: 13
 			// eclipse.platform.ui: 7
 			max = pathFilters[0].pathRaw;
 			Hasher hasher = new Hasher(null, 0);
 			for (PathFilter pf : pathFilters) {
 				hasher.init(pf.pathRaw, pf.pathRaw.length);
 				while (hasher.hasNext()) {
 					int hash = hasher.nextHash();
 					if (hasher.hasNext())
 						prefixes.addIfAbsent(pf.pathRaw, hasher.length(), hash);
 				}
 				fullpaths.addIfAbsent(pf.pathRaw, pf.pathRaw.length,
 						hasher.getHash());
 				if (compare(max, pf.pathRaw) < 0)
 					max = pf.pathRaw;
 			}
 			// Adjust max for the git sort order. A path we compare
 			// with may end with a slash at any position (but the
 			// first, but we ignore that here since it's not relevant).
 			// Such paths must be included in the processing
 			// before we can give up and throw a StopWalkException.
 			byte[] newMax = new byte[max.length + 1];
 			for (int i = 0; i < max.length; ++i)
 				if ((max[i] & 0xFF) < '/')
 					newMax[i] = '/';
 				else
 					newMax[i] = max[i];
 			newMax[newMax.length - 1] = '/';
 			max = newMax;
 		}

 		private static int compare(byte[] a, byte[] b) {
 			int i = 0;
 			while (i < a.length && i < b.length) {
 				int ba = a[i] & 0xFF;
 				int bb = b[i] & 0xFF;
 				int cmp = ba - bb;
 				if (cmp != 0)
 					return cmp;
 				++i;
 			}
 			return a.length - b.length;
 		}

 		@Override
 		public boolean include(TreeWalk walker) {

 			byte[] rp = walker.getRawPath();
 			Hasher hasher = new Hasher(rp, walker.getPathLength());
 			while (hasher.hasNext()) {
 				int hash = hasher.nextHash();
 				if (fullpaths.contains(rp, hasher.length(), hash))
 					return true;
 				if (!hasher.hasNext() && walker.isSubtree()
 						&& prefixes.contains(rp, hasher.length(), hash))
 					return true;
 			}

 			final int cmp = walker.isPathPrefix(max, max.length);
 			if (cmp > 0)
 				throw StopWalkException.INSTANCE;

 			return false;
 		}

 		@Override
 		public boolean shouldBeRecursive() {
 			return !prefixes.isEmpty();
 		}

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

 		@Override
 		public String toString() {
 			final StringBuilder r = new StringBuilder();
 			r.append("FAST("); //$NON-NLS-1$
 			boolean first = true;
 			for (byte[] p : fullpaths.toArray()) {
 				if (!first) {
 					r.append(" OR "); //$NON-NLS-1$
 				}
 				r.append(RawParseUtils.decode(p));
 				first = false;
 			}
 			r.append(")"); //$NON-NLS-1$
 			return r.toString();
 		}
 	}

 }
	/*
	* Copyright (C) 2007, Robin Rosenberg <robin.rosenberg@dewire.com>
	* Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org> and others
	*
	* This program and the accompanying materials are made available under the
	* terms of the Eclipse Distribution License v. 1.0 which is available at
	* https://www.eclipse.org/org/documents/edl-v10.php.
	*
	* SPDX-License-Identifier: BSD-3-Clause
	*/

	package org.eclipse.jgit.treewalk.filter;

	import java.util.Collection;

	import org.eclipse.jgit.errors.StopWalkException;
	import org.eclipse.jgit.internal.JGitText;
	import org.eclipse.jgit.treewalk.TreeWalk;
	import org.eclipse.jgit.treewalk.filter.ByteArraySet.Hasher;
	import org.eclipse.jgit.util.RawParseUtils;

	/**
	* Includes tree entries only if they match one or more configured paths.
	* <p>
	* Operates like {@link org.eclipse.jgit.treewalk.filter.PathFilter} but causes
	* the walk to abort as soon as the tree can no longer match any of the paths
	* within the group. This may bypass the boolean logic of a higher level AND or
	* OR group, but does improve performance for the common case of examining one
	* or more modified paths.
	* <p>
	* This filter is effectively an OR group around paths, with the early abort
	* feature described above.
	*/
	public class PathFilterGroup {
	/**
	* Create a collection of path filters from Java strings.
	* <p>
	* Path strings are relative to the root of the repository. If the user's
	* input should be assumed relative to a subdirectory of the repository the
	* caller must prepend the subdirectory's path prior to creating the filter.
	* <p>
	* Path strings use '/' to delimit directories on all platforms.
	* <p>
	* Paths may appear in any order within the collection. Sorting may be done
	* internally when the group is constructed if doing so will improve path
	* matching performance.
	*
	* @param paths
	* the paths to test against. Must have at least one entry.
	* @return a new filter for the list of paths supplied.
	*/
	public static TreeFilter createFromStrings(Collection<String> paths) {
	if (paths.isEmpty())
	throw new IllegalArgumentException(
	JGitText.get().atLeastOnePathIsRequired);
	final PathFilter[] p = new PathFilter[paths.size()];
	int i = 0;
	for (String s : paths)
	p[i++] = PathFilter.create(s);
	return create(p);
	}

	/**
	* Create a collection of path filters from Java strings.
	* <p>
	* Path strings are relative to the root of the repository. If the user's
	* input should be assumed relative to a subdirectory of the repository the
	* caller must prepend the subdirectory's path prior to creating the filter.
	* <p>
	* Path strings use '/' to delimit directories on all platforms.
	* <p>
	* Paths may appear in any order. Sorting may be done internally when the
	* group is constructed if doing so will improve path matching performance.
	*
	* @param paths
	* the paths to test against. Must have at least one entry.
	* @return a new filter for the paths supplied.
	*/
	public static TreeFilter createFromStrings(String... paths) {
	if (paths.length == 0)
	throw new IllegalArgumentException(
	JGitText.get().atLeastOnePathIsRequired);
	final int length = paths.length;
	final PathFilter[] p = new PathFilter[length];
	for (int i = 0; i < length; i++)
	p[i] = PathFilter.create(paths[i]);
	return create(p);
	}

	/**
	* Create a collection of path filters.
	* <p>
	* Paths may appear in any order within the collection. Sorting may be done
	* internally when the group is constructed if doing so will improve path
	* matching performance.
	*
	* @param paths
	* the paths to test against. Must have at least one entry.
	* @return a new filter for the list of paths supplied.
	*/
	public static TreeFilter create(Collection<PathFilter> paths) {
	if (paths.isEmpty())
	throw new IllegalArgumentException(
	JGitText.get().atLeastOnePathIsRequired);
	final PathFilter[] p = new PathFilter[paths.size()];
	paths.toArray(p);
	return create(p);
	}

	private static TreeFilter create(PathFilter[] p) {
	if (p.length == 1)
	return new Single(p[0]);
	return new Group(p);
	}

	static class Single extends TreeFilter {
	private final PathFilter path;

	private final byte[] raw;

	private Single(PathFilter p) {
	path = p;
	raw = path.pathRaw;
	}

	@Override
	public boolean include(TreeWalk walker) {
	final int cmp = walker.isPathPrefix(raw, raw.length);
	if (cmp > 0)
	throw StopWalkException.INSTANCE;
	return cmp == 0;
	}

	@Override
	public boolean shouldBeRecursive() {
	return path.shouldBeRecursive();
	}

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

	@Override
	public String toString() {
	return "FAST_" + path.toString(); //$NON-NLS-1$
	}
	}

	static class Group extends TreeFilter {

	private ByteArraySet fullpaths;

	private ByteArraySet prefixes;

	private byte[] max;

	private Group(PathFilter[] pathFilters) {
	fullpaths = new ByteArraySet(pathFilters.length);
	prefixes = new ByteArraySet(pathFilters.length / 5);
	// 5 is an empirically derived ratio of #paths/#prefixes from:
	// egit/jgit: 8
	// git: 5
	// linux kernel: 13
	// eclipse.platform.ui: 7
	max = pathFilters[0].pathRaw;
	Hasher hasher = new Hasher(null, 0);
	for (PathFilter pf : pathFilters) {
	hasher.init(pf.pathRaw, pf.pathRaw.length);
	while (hasher.hasNext()) {
	int hash = hasher.nextHash();
	if (hasher.hasNext())
	prefixes.addIfAbsent(pf.pathRaw, hasher.length(), hash);
	}
	fullpaths.addIfAbsent(pf.pathRaw, pf.pathRaw.length,
	hasher.getHash());
	if (compare(max, pf.pathRaw) < 0)
	max = pf.pathRaw;
	}
	// Adjust max for the git sort order. A path we compare
	// with may end with a slash at any position (but the
	// first, but we ignore that here since it's not relevant).
	// Such paths must be included in the processing
	// before we can give up and throw a StopWalkException.
	byte[] newMax = new byte[max.length + 1];
	for (int i = 0; i < max.length; ++i)
	if ((max[i] & 0xFF) < '/')
	newMax[i] = '/';
	else
	newMax[i] = max[i];
	newMax[newMax.length - 1] = '/';
	max = newMax;
	}

	private static int compare(byte[] a, byte[] b) {
	int i = 0;
	while (i < a.length && i < b.length) {
	int ba = a[i] & 0xFF;
	int bb = b[i] & 0xFF;
	int cmp = ba - bb;
	if (cmp != 0)
	return cmp;
	++i;
	}
	return a.length - b.length;
	}

	@Override
	public boolean include(TreeWalk walker) {

	byte[] rp = walker.getRawPath();
	Hasher hasher = new Hasher(rp, walker.getPathLength());
	while (hasher.hasNext()) {
	int hash = hasher.nextHash();
	if (fullpaths.contains(rp, hasher.length(), hash))
	return true;
	if (!hasher.hasNext() && walker.isSubtree()
	&& prefixes.contains(rp, hasher.length(), hash))
	return true;
	}

	final int cmp = walker.isPathPrefix(max, max.length);
	if (cmp > 0)
	throw StopWalkException.INSTANCE;

	return false;
	}

	@Override
	public boolean shouldBeRecursive() {
	return !prefixes.isEmpty();
	}

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

	@Override
	public String toString() {
	final StringBuilder r = new StringBuilder();
	r.append("FAST("); //$NON-NLS-1$
	boolean first = true;
	for (byte[] p : fullpaths.toArray()) {
	if (!first) {
	r.append(" OR "); //$NON-NLS-1$
	}
	r.append(RawParseUtils.decode(p));
	first = false;
	}
	r.append(")"); //$NON-NLS-1$
	return r.toString();
	}
	}

	}