/*
* Copyright (C) 2008-2009, Google Inc.
* 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
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package org.eclipse.jgit.treewalk;
import java.io.IOException;
import org.eclipse.jgit.errors.CorruptObjectException;
import org.eclipse.jgit.errors.IncorrectObjectTypeException;
import org.eclipse.jgit.errors.MissingObjectException;
import org.eclipse.jgit.errors.StopWalkException;
import org.eclipse.jgit.lib.AnyObjectId;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.lib.FileMode;
import org.eclipse.jgit.lib.MutableObjectId;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.ObjectReader;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.revwalk.RevTree;
import org.eclipse.jgit.treewalk.filter.PathFilter;
import org.eclipse.jgit.treewalk.filter.TreeFilter;
import org.eclipse.jgit.util.RawParseUtils;
/**
* Walks one or more {@link AbstractTreeIterator}s in parallel.
* <p>
* This class can perform n-way differences across as many trees as necessary.
* <p>
* Each tree added must have the same root as existing trees in the walk.
* <p>
* A TreeWalk instance can only be used once to generate results. Running a
* second time requires creating a new TreeWalk instance, or invoking
* {@link #reset()} and adding new trees before starting again. Resetting an
* existing instance may be faster for some applications as some internal
* buffers may be recycled.
* <p>
* TreeWalk instances are not thread-safe. Applications must either restrict
* usage of a TreeWalk instance to a single thread, or implement their own
* synchronization at a higher level.
* <p>
* Multiple simultaneous TreeWalk instances per {@link Repository} are
* permitted, even from concurrent threads.
*/
public class TreeWalk {
private static final AbstractTreeIterator[] NO_TREES = {};
/**
* Open a tree walk and filter to exactly one path.
* <p>
* The returned tree walk is already positioned on the requested path, so
* the caller should not need to invoke {@link #next()} unless they are
* looking for a possible directory/file name conflict.
*
* @param reader
* the reader the walker will obtain tree data from.
* @param path
* single path to advance the tree walk instance into.
* @param trees
* one or more trees to walk through, all with the same root.
* @return a new tree walk configured for exactly this one path; null if no
* path was found in any of the trees.
* @throws IOException
* reading a pack file or loose object failed.
* @throws CorruptObjectException
* an tree object could not be read as its data stream did not
* appear to be a tree, or could not be inflated.
* @throws IncorrectObjectTypeException
* an object we expected to be a tree was not a tree.
* @throws MissingObjectException
* a tree object was not found.
*/
public static TreeWalk forPath(final ObjectReader reader, final String path,
final AnyObjectId... trees) throws MissingObjectException,
IncorrectObjectTypeException, CorruptObjectException, IOException {
TreeWalk tw = new TreeWalk(reader);
PathFilter f = PathFilter.create(path);
tw.setFilter(f);
tw.reset(trees);
tw.setRecursive(false);
while (tw.next()) {
if (f.isDone(tw)) {
return tw;
} else if (tw.isSubtree()) {
tw.enterSubtree();
}
}
return null;
}
/**
* Open a tree walk and filter to exactly one path.
* <p>
* The returned tree walk is already positioned on the requested path, so
* the caller should not need to invoke {@link #next()} unless they are
* looking for a possible directory/file name conflict.
*
* @param db
* repository to read tree object data from.
* @param path
* single path to advance the tree walk instance into.
* @param trees
* one or more trees to walk through, all with the same root.
* @return a new tree walk configured for exactly this one path; null if no
* path was found in any of the trees.
* @throws IOException
* reading a pack file or loose object failed.
* @throws CorruptObjectException
* an tree object could not be read as its data stream did not
* appear to be a tree, or could not be inflated.
* @throws IncorrectObjectTypeException
* an object we expected to be a tree was not a tree.
* @throws MissingObjectException
* a tree object was not found.
*/
public static TreeWalk forPath(final Repository db, final String path,
final AnyObjectId... trees) throws MissingObjectException,
IncorrectObjectTypeException, CorruptObjectException, IOException {
ObjectReader reader = db.newObjectReader();
try {
return forPath(reader, path, trees);
} finally {
reader.release();
}
}
/**
* Open a tree walk and filter to exactly one path.
* <p>
* The returned tree walk is already positioned on the requested path, so
* the caller should not need to invoke {@link #next()} unless they are
* looking for a possible directory/file name conflict.
*
* @param db
* repository to read tree object data from.
* @param path
* single path to advance the tree walk instance into.
* @param tree
* the single tree to walk through.
* @return a new tree walk configured for exactly this one path; null if no
* path was found in any of the trees.
* @throws IOException
* reading a pack file or loose object failed.
* @throws CorruptObjectException
* an tree object could not be read as its data stream did not
* appear to be a tree, or could not be inflated.
* @throws IncorrectObjectTypeException
* an object we expected to be a tree was not a tree.
* @throws MissingObjectException
* a tree object was not found.
*/
public static TreeWalk forPath(final Repository db, final String path,
final RevTree tree) throws MissingObjectException,
IncorrectObjectTypeException, CorruptObjectException, IOException {
return forPath(db, path, new ObjectId[] { tree });
}
private final ObjectReader reader;
private final MutableObjectId idBuffer = new MutableObjectId();
private TreeFilter filter;
AbstractTreeIterator[] trees;
private boolean recursive;
private boolean postOrderTraversal;
private int depth;
private boolean advance;
private boolean postChildren;
AbstractTreeIterator currentHead;
/**
* Create a new tree walker for a given repository.
*
* @param repo
* the repository the walker will obtain data from.
*/
public TreeWalk(final Repository repo) {
this(repo.newObjectReader());
}
/**
* Create a new tree walker for a given repository.
*
* @param or
* the reader the walker will obtain tree data from.
*/
public TreeWalk(final ObjectReader or) {
reader = or;
filter = TreeFilter.ALL;
trees = NO_TREES;
}
/** @return the reader this walker is using to load objects. */
public ObjectReader getObjectReader() {
return reader;
}
/**
* Release any resources used by this walker's reader.
* <p>
* A walker that has been released can be used again, but may need to be
* released after the subsequent usage.
*/
public void release() {
reader.release();
}
/**
* Get the currently configured filter.
*
* @return the current filter. Never null as a filter is always needed.
*/
public TreeFilter getFilter() {
return filter;
}
/**
* Set the tree entry filter for this walker.
* <p>
* Multiple filters may be combined by constructing an arbitrary tree of
* <code>AndTreeFilter</code> or <code>OrTreeFilter</code> instances to
* describe the boolean expression required by the application. Custom
* filter implementations may also be constructed by applications.
* <p>
* Note that filters are not thread-safe and may not be shared by concurrent
* TreeWalk instances. Every TreeWalk must be supplied its own unique
* filter, unless the filter implementation specifically states it is (and
* always will be) thread-safe. Callers may use {@link TreeFilter#clone()}
* to create a unique filter tree for this TreeWalk instance.
*
* @param newFilter
* the new filter. If null the special {@link TreeFilter#ALL}
* filter will be used instead, as it matches every entry.
* @see org.eclipse.jgit.treewalk.filter.AndTreeFilter
* @see org.eclipse.jgit.treewalk.filter.OrTreeFilter
*/
public void setFilter(final TreeFilter newFilter) {
filter = newFilter != null ? newFilter : TreeFilter.ALL;
}
/**
* Is this walker automatically entering into subtrees?
* <p>
* If the walker is recursive then the caller will not see a subtree node
* and instead will only receive file nodes in all relevant subtrees.
*
* @return true if automatically entering subtrees is enabled.
*/
public boolean isRecursive() {
return recursive;
}
/**
* Set the walker to enter (or not enter) subtrees automatically.
* <p>
* If recursive mode is enabled the walker will hide subtree nodes from the
* calling application and will produce only file level nodes. If a tree
* (directory) is deleted then all of the file level nodes will appear to be
* deleted, recursively, through as many levels as necessary to account for
* all entries.
*
* @param b
* true to skip subtree nodes and only obtain files nodes.
*/
public void setRecursive(final boolean b) {
recursive = b;
}
/**
* Does this walker return a tree entry after it exits the subtree?
* <p>
* If post order traversal is enabled then the walker will return a subtree
* after it has returned the last entry within that subtree. This may cause
* a subtree to be seen by the application twice if {@link #isRecursive()}
* is false, as the application will see it once, call
* {@link #enterSubtree()}, and then see it again as it leaves the subtree.
* <p>
* If an application does not enable {@link #isRecursive()} and it does not
* call {@link #enterSubtree()} then the tree is returned only once as none
* of the children were processed.
*
* @return true if subtrees are returned after entries within the subtree.
*/
public boolean isPostOrderTraversal() {
return postOrderTraversal;
}
/**
* Set the walker to return trees after their children.
*
* @param b
* true to get trees after their children.
* @see #isPostOrderTraversal()
*/
public void setPostOrderTraversal(final boolean b) {
postOrderTraversal = b;
}
/** Reset this walker so new tree iterators can be added to it. */
public void reset() {
trees = NO_TREES;
advance = false;
depth = 0;
}
/**
* Reset this walker to run over a single existing tree.
*
* @param id
* the tree we need to parse. The walker will execute over this
* single tree if the reset is successful.
* @throws MissingObjectException
* the given tree object does not exist in this repository.
* @throws IncorrectObjectTypeException
* the given object id does not denote a tree, but instead names
* some other non-tree type of object. Note that commits are not
* trees, even if they are sometimes called a "tree-ish".
* @throws CorruptObjectException
* the object claimed to be a tree, but its contents did not
* appear to be a tree. The repository may have data corruption.
* @throws IOException
* a loose object or pack file could not be read.
*/
public void reset(final AnyObjectId id) throws MissingObjectException,
IncorrectObjectTypeException, CorruptObjectException, IOException {
if (trees.length == 1) {
AbstractTreeIterator o = trees[0];
while (o.parent != null)
o = o.parent;
if (o instanceof CanonicalTreeParser) {
o.matches = null;
o.matchShift = 0;
((CanonicalTreeParser) o).reset(reader, id);
trees[0] = o;
} else {
trees[0] = parserFor(id);
}
} else {
trees = new AbstractTreeIterator[] { parserFor(id) };
}
advance = false;
depth = 0;
}
/**
* Reset this walker to run over a set of existing trees.
*
* @param ids
* the trees we need to parse. The walker will execute over this
* many parallel trees if the reset is successful.
* @throws MissingObjectException
* the given tree object does not exist in this repository.
* @throws IncorrectObjectTypeException
* the given object id does not denote a tree, but instead names
* some other non-tree type of object. Note that commits are not
* trees, even if they are sometimes called a "tree-ish".
* @throws CorruptObjectException
* the object claimed to be a tree, but its contents did not
* appear to be a tree. The repository may have data corruption.
* @throws IOException
* a loose object or pack file could not be read.
*/
public void reset(final AnyObjectId... ids) throws MissingObjectException,
IncorrectObjectTypeException, CorruptObjectException, IOException {
final int oldLen = trees.length;
final int newLen = ids.length;
final AbstractTreeIterator[] r = newLen == oldLen ? trees
: new AbstractTreeIterator[newLen];
for (int i = 0; i < newLen; i++) {
AbstractTreeIterator o;
if (i < oldLen) {
o = trees[i];
while (o.parent != null)
o = o.parent;
if (o instanceof CanonicalTreeParser && o.pathOffset == 0) {
o.matches = null;
o.matchShift = 0;
((CanonicalTreeParser) o).reset(reader, ids[i]);
r[i] = o;
continue;
}
}
o = parserFor(ids[i]);
r[i] = o;
}
trees = r;
advance = false;
depth = 0;
}
/**
* Add an already existing tree object for walking.
* <p>
* The position of this tree is returned to the caller, in case the caller
* has lost track of the order they added the trees into the walker.
* <p>
* The tree must have the same root as existing trees in the walk.
*
* @param id
* identity of the tree object the caller wants walked.
* @return position of this tree within the walker.
* @throws MissingObjectException
* the given tree object does not exist in this repository.
* @throws IncorrectObjectTypeException
* the given object id does not denote a tree, but instead names
* some other non-tree type of object. Note that commits are not
* trees, even if they are sometimes called a "tree-ish".
* @throws CorruptObjectException
* the object claimed to be a tree, but its contents did not
* appear to be a tree. The repository may have data corruption.
* @throws IOException
* a loose object or pack file could not be read.
*/
public int addTree(final AnyObjectId id) throws MissingObjectException,
IncorrectObjectTypeException, CorruptObjectException, IOException {
return addTree(parserFor(id));
}
/**
* Add an already created tree iterator for walking.
* <p>
* The position of this tree is returned to the caller, in case the caller
* has lost track of the order they added the trees into the walker.
* <p>
* The tree which the iterator operates on must have the same root as
* existing trees in the walk.
*
* @param p
* an iterator to walk over. The iterator should be new, with no
* parent, and should still be positioned before the first entry.
* The tree which the iterator operates on must have the same root
* as other trees in the walk.
*
* @return position of this tree within the walker.
* @throws CorruptObjectException
* the iterator was unable to obtain its first entry, due to
* possible data corruption within the backing data store.
*/
public int addTree(final AbstractTreeIterator p)
throws CorruptObjectException {
final int n = trees.length;
final AbstractTreeIterator[] newTrees = new AbstractTreeIterator[n + 1];
System.arraycopy(trees, 0, newTrees, 0, n);
newTrees[n] = p;
p.matches = null;
p.matchShift = 0;
trees = newTrees;
return n;
}
/**
* Get the number of trees known to this walker.
*
* @return the total number of trees this walker is iterating over.
*/
public int getTreeCount() {
return trees.length;
}
/**
* Advance this walker to the next relevant entry.
*
* @return true if there is an entry available; false if all entries have
* been walked and the walk of this set of tree iterators is over.
* @throws MissingObjectException
* {@link #isRecursive()} was enabled, a subtree was found, but
* the subtree object does not exist in this repository. The
* repository may be missing objects.
* @throws IncorrectObjectTypeException
* {@link #isRecursive()} was enabled, a subtree was found, and
* the subtree id does not denote a tree, but instead names some
* other non-tree type of object. The repository may have data
* corruption.
* @throws CorruptObjectException
* the contents of a tree did not appear to be a tree. The
* repository may have data corruption.
* @throws IOException
* a loose object or pack file could not be read.
*/
public boolean next() throws MissingObjectException,
IncorrectObjectTypeException, CorruptObjectException, IOException {
try {
if (advance) {
advance = false;
postChildren = false;
popEntriesEqual();
}
for (;;) {
final AbstractTreeIterator t = min();
if (t.eof()) {
if (depth > 0) {
exitSubtree();
if (postOrderTraversal) {
advance = true;
postChildren = true;
return true;
}
popEntriesEqual();
continue;
}
return false;
}
currentHead = t;
if (!filter.include(this)) {
skipEntriesEqual();
continue;
}
if (recursive && FileMode.TREE.equals(t.mode)) {
enterSubtree();
continue;
}
advance = true;
return true;
}
} catch (StopWalkException stop) {
for (final AbstractTreeIterator t : trees)
t.stopWalk();
return false;
}
}
/**
* Obtain the tree iterator for the current entry.
* <p>
* Entering into (or exiting out of) a subtree causes the current tree
* iterator instance to be changed for the nth tree. This allows the tree
* iterators to manage only one list of items, with the diving handled by
* recursive trees.
*
* @param <T>
* type of the tree iterator expected by the caller.
* @param nth
* tree to obtain the current iterator of.
* @param clazz
* type of the tree iterator expected by the caller.
* @return r the current iterator of the requested type; null if the tree
* has no entry to match the current path.
*/
public <T extends AbstractTreeIterator> T getTree(final int nth,
final Class<T> clazz) {
final AbstractTreeIterator t = trees[nth];
return t.matches == currentHead ? (T) t : null;
}
/**
* Obtain the raw {@link FileMode} bits for the current entry.
* <p>
* Every added tree supplies mode bits, even if the tree does not contain
* the current entry. In the latter case {@link FileMode#MISSING}'s mode
* bits (0) are returned.
*
* @param nth
* tree to obtain the mode bits from.
* @return mode bits for the current entry of the nth tree.
* @see FileMode#fromBits(int)
*/
public int getRawMode(final int nth) {
final AbstractTreeIterator t = trees[nth];
return t.matches == currentHead ? t.mode : 0;
}
/**
* Obtain the {@link FileMode} for the current entry.
* <p>
* Every added tree supplies a mode, even if the tree does not contain the
* current entry. In the latter case {@link FileMode#MISSING} is returned.
*
* @param nth
* tree to obtain the mode from.
* @return mode for the current entry of the nth tree.
*/
public FileMode getFileMode(final int nth) {
return FileMode.fromBits(getRawMode(nth));
}
/**
* Obtain the ObjectId for the current entry.
* <p>
* Using this method to compare ObjectId values between trees of this walker
* is very inefficient. Applications should try to use
* {@link #idEqual(int, int)} or {@link #getObjectId(MutableObjectId, int)}
* whenever possible.
* <p>
* Every tree supplies an object id, even if the tree does not contain the
* current entry. In the latter case {@link ObjectId#zeroId()} is returned.
*
* @param nth
* tree to obtain the object identifier from.
* @return object identifier for the current tree entry.
* @see #getObjectId(MutableObjectId, int)
* @see #idEqual(int, int)
*/
public ObjectId getObjectId(final int nth) {
final AbstractTreeIterator t = trees[nth];
return t.matches == currentHead ? t.getEntryObjectId() : ObjectId
.zeroId();
}
/**
* Obtain the ObjectId for the current entry.
* <p>
* Every tree supplies an object id, even if the tree does not contain the
* current entry. In the latter case {@link ObjectId#zeroId()} is supplied.
* <p>
* Applications should try to use {@link #idEqual(int, int)} when possible
* as it avoids conversion overheads.
*
* @param out
* buffer to copy the object id into.
* @param nth
* tree to obtain the object identifier from.
* @see #idEqual(int, int)
*/
public void getObjectId(final MutableObjectId out, final int nth) {
final AbstractTreeIterator t = trees[nth];
if (t.matches == currentHead)
t.getEntryObjectId(out);
else
out.clear();
}
/**
* Compare two tree's current ObjectId values for equality.
*
* @param nthA
* first tree to compare the object id from.
* @param nthB
* second tree to compare the object id from.
* @return result of
* <code>getObjectId(nthA).equals(getObjectId(nthB))</code>.
* @see #getObjectId(int)
*/
public boolean idEqual(final int nthA, final int nthB) {
final AbstractTreeIterator ch = currentHead;
final AbstractTreeIterator a = trees[nthA];
final AbstractTreeIterator b = trees[nthB];
if (a.matches != ch && b.matches != ch) {
// If neither tree matches the current path node then neither
// tree has this entry. In such case the ObjectId is zero(),
// and zero() is always equal to zero().
//
return true;
}
if (!a.hasId() || !b.hasId())
return false;
if (a.matches == ch && b.matches == ch)
return a.idEqual(b);
return false;
}
/**
* Get the current entry's name within its parent tree.
* <p>
* This method is not very efficient and is primarily meant for debugging
* and final output generation. Applications should try to avoid calling it,
* and if invoked do so only once per interesting entry, where the name is
* absolutely required for correct function.
*
* @return name of the current entry within the parent tree (or directory).
* The name never includes a '/'.
*/
public String getNameString() {
final AbstractTreeIterator t = currentHead;
final int off = t.pathOffset;
final int end = t.pathLen;
return RawParseUtils.decode(Constants.CHARSET, t.path, off, end);
}
/**
* Get the current entry's complete path.
* <p>
* This method is not very efficient and is primarily meant for debugging
* and final output generation. Applications should try to avoid calling it,
* and if invoked do so only once per interesting entry, where the name is
* absolutely required for correct function.
*
* @return complete path of the current entry, from the root of the
* repository. If the current entry is in a subtree there will be at
* least one '/' in the returned string.
*/
public String getPathString() {
return pathOf(currentHead);
}
/**
* Get the current entry's complete path as a UTF-8 byte array.
*
* @return complete path of the current entry, from the root of the
* repository. If the current entry is in a subtree there will be at
* least one '/' in the returned string.
*/
public byte[] getRawPath() {
final AbstractTreeIterator t = currentHead;
final int n = t.pathLen;
final byte[] r = new byte[n];
System.arraycopy(t.path, 0, r, 0, n);
return r;
}
/**
* @return The path length of the current entry.
*/
public int getPathLength() {
return currentHead.pathLen;
}
/**
* Test if the supplied path matches the current entry's path.
* <p>
* This method tests that the supplied path is exactly equal to the current
* entry, or is one of its parent directories. It is faster to use this
* method then to use {@link #getPathString()} to first create a String
* object, then test <code>startsWith</code> or some other type of string
* match function.
*
* @param p
* path buffer to test. Callers should ensure the path does not
* end with '/' prior to invocation.
* @param pLen
* number of bytes from <code>buf</code> to test.
* @return < 0 if p is before the current path; 0 if p matches the current
* path; 1 if the current path is past p and p will never match
* again on this tree walk.
*/
public int isPathPrefix(final byte[] p, final int pLen) {
final AbstractTreeIterator t = currentHead;
final byte[] c = t.path;
final int cLen = t.pathLen;
int ci;
for (ci = 0; ci < cLen && ci < pLen; ci++) {
final int c_value = (c[ci] & 0xff) - (p[ci] & 0xff);
if (c_value != 0)
return c_value;
}
if (ci < cLen) {
// Ran out of pattern but we still had current data.
// If c[ci] == '/' then pattern matches the subtree.
// Otherwise we cannot be certain so we return -1.
//
return c[ci] == '/' ? 0 : -1;
}
if (ci < pLen) {
// Ran out of current, but we still have pattern data.
// If p[ci] == '/' then pattern matches this subtree,
// otherwise we cannot be certain so we return -1.
//
return p[ci] == '/' ? 0 : -1;
}
// Both strings are identical.
//
return 0;
}
/**
* Test if the supplied path matches (being suffix of) the current entry's
* path.
* <p>
* This method tests that the supplied path is exactly equal to the current
* entry, or is relative to one of entry's parent directories. It is faster
* to use this method then to use {@link #getPathString()} to first create
* a String object, then test <code>endsWith</code> or some other type of
* string match function.
*
* @param p
* path buffer to test.
* @param pLen
* number of bytes from <code>buf</code> to test.
* @return true if p is suffix of the current path;
* false if otherwise
*/
public boolean isPathSuffix(final byte[] p, final int pLen) {
final AbstractTreeIterator t = currentHead;
final byte[] c = t.path;
final int cLen = t.pathLen;
int ci;
for (ci = 1; ci < cLen && ci < pLen; ci++) {
if (c[cLen-ci] != p[pLen-ci])
return false;
}
return true;
}
/**
* Get the current subtree depth of this walker.
*
* @return the current subtree depth of this walker.
*/
public int getDepth() {
return depth;
}
/**
* Is the current entry a subtree?
* <p>
* This method is faster then testing the raw mode bits of all trees to see
* if any of them are a subtree. If at least one is a subtree then this
* method will return true.
*
* @return true if {@link #enterSubtree()} will work on the current node.
*/
public boolean isSubtree() {
return FileMode.TREE.equals(currentHead.mode);
}
/**
* Is the current entry a subtree returned after its children?
*
* @return true if the current node is a tree that has been returned after
* its children were already processed.
* @see #isPostOrderTraversal()
*/
public boolean isPostChildren() {
return postChildren && isSubtree();
}
/**
* Enter into the current subtree.
* <p>
* If the current entry is a subtree this method arranges for its children
* to be returned before the next sibling following the subtree is returned.
*
* @throws MissingObjectException
* a subtree was found, but the subtree object does not exist in
* this repository. The repository may be missing objects.
* @throws IncorrectObjectTypeException
* a subtree was found, and the subtree id does not denote a
* tree, but instead names some other non-tree type of object.
* The repository may have data corruption.
* @throws CorruptObjectException
* the contents of a tree did not appear to be a tree. The
* repository may have data corruption.
* @throws IOException
* a loose object or pack file could not be read.
*/
public void enterSubtree() throws MissingObjectException,
IncorrectObjectTypeException, CorruptObjectException, IOException {
final AbstractTreeIterator ch = currentHead;
final AbstractTreeIterator[] tmp = new AbstractTreeIterator[trees.length];
for (int i = 0; i < trees.length; i++) {
final AbstractTreeIterator t = trees[i];
final AbstractTreeIterator n;
if (t.matches == ch && !t.eof() && FileMode.TREE.equals(t.mode))
n = t.createSubtreeIterator(reader, idBuffer);
else
n = t.createEmptyTreeIterator();
tmp[i] = n;
}
depth++;
advance = false;
System.arraycopy(tmp, 0, trees, 0, trees.length);
}
AbstractTreeIterator min() throws CorruptObjectException {
int i = 0;
AbstractTreeIterator minRef = trees[i];
while (minRef.eof() && ++i < trees.length)
minRef = trees[i];
if (minRef.eof())
return minRef;
minRef.matches = minRef;
while (++i < trees.length) {
final AbstractTreeIterator t = trees[i];
if (t.eof())
continue;
final int cmp = t.pathCompare(minRef);
if (cmp < 0) {
t.matches = t;
minRef = t;
} else if (cmp == 0) {
t.matches = minRef;
}
}
return minRef;
}
void popEntriesEqual() throws CorruptObjectException {
final AbstractTreeIterator ch = currentHead;
for (int i = 0; i < trees.length; i++) {
final AbstractTreeIterator t = trees[i];
if (t.matches == ch) {
t.next(1);
t.matches = null;
}
}
}
void skipEntriesEqual() throws CorruptObjectException {
final AbstractTreeIterator ch = currentHead;
for (int i = 0; i < trees.length; i++) {
final AbstractTreeIterator t = trees[i];
if (t.matches == ch) {
t.skip();
t.matches = null;
}
}
}
private void exitSubtree() {
depth--;
for (int i = 0; i < trees.length; i++)
trees[i] = trees[i].parent;
AbstractTreeIterator minRef = null;
for (final AbstractTreeIterator t : trees) {
if (t.matches != t)
continue;
if (minRef == null || t.pathCompare(minRef) < 0)
minRef = t;
}
currentHead = minRef;
}
private CanonicalTreeParser parserFor(final AnyObjectId id)
throws IncorrectObjectTypeException, IOException {
final CanonicalTreeParser p = new CanonicalTreeParser();
p.reset(reader, id);
return p;
}
static String pathOf(final AbstractTreeIterator t) {
return RawParseUtils.decode(Constants.CHARSET, t.path, 0, t.pathLen);
}
static String pathOf(final byte[] buf, int pos, int end) {
return RawParseUtils.decode(Constants.CHARSET, buf, pos, end);
}
}