| // Copyright (C) 2009 The Android Open Source Project |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package com.google.gerrit.server.patch; |
| |
| import com.google.gerrit.client.reviewdb.Patch; |
| import com.google.gerrit.client.reviewdb.RevId; |
| import com.google.gerrit.client.rpc.CorruptEntityException; |
| import com.google.gerrit.client.rpc.NoSuchEntityException; |
| |
| import org.spearce.jgit.errors.CorruptObjectException; |
| import org.spearce.jgit.errors.IncorrectObjectTypeException; |
| import org.spearce.jgit.errors.MissingObjectException; |
| import org.spearce.jgit.lib.Constants; |
| import org.spearce.jgit.lib.ObjectId; |
| import org.spearce.jgit.lib.ObjectLoader; |
| import org.spearce.jgit.lib.ObjectWriter; |
| import org.spearce.jgit.lib.Repository; |
| import org.spearce.jgit.revwalk.RevCommit; |
| import org.spearce.jgit.revwalk.RevWalk; |
| |
| import java.io.IOException; |
| import java.nio.charset.CharacterCodingException; |
| |
| /** State supporting processing of a single {@link Patch} instance. */ |
| public class PatchFile { |
| private final Repository repo; |
| private final Patch patch; |
| private final ObjectId aTree; |
| private final ObjectId bTree; |
| |
| private Text a; |
| private Text b; |
| |
| public PatchFile(final Repository repo, final RevId id, final Patch patch) |
| throws MissingObjectException, IncorrectObjectTypeException, IOException { |
| this.repo = repo; |
| this.patch = patch; |
| |
| final RevWalk rw = new RevWalk(repo); |
| final RevCommit bCommit = rw.parseCommit(ObjectId.fromString(id.get())); |
| if (bCommit.getParentCount() > 0) { |
| rw.parse(bCommit.getParent(0)); |
| aTree = bCommit.getParent(0).getTree(); |
| } else { |
| aTree = emptyTree(); |
| } |
| bTree = bCommit.getTree(); |
| } |
| |
| /** |
| * Extract a line from the file, as a string. |
| * |
| * @param file the file index to extract. |
| * @param line the line number to extract (1 based; 1 is the first line). |
| * @return the string version of the file line. |
| * @throws CorruptEntityException the patch cannot be read. |
| * @throws IOException the patch or complete file content cannot be read. |
| * @throws NoSuchEntityException |
| * @throws CharacterCodingException the file is not a known character set. |
| */ |
| public String getLine(final int file, final int line) |
| throws CorruptEntityException, IOException, NoSuchEntityException { |
| switch (file) { |
| case 0: |
| if (a == null) { |
| String p = patch.getSourceFileName(); |
| if (p == null) { |
| p = patch.getFileName(); |
| } |
| a = load(aTree, p); |
| } |
| return a.getLine(line - 1); |
| |
| case 1: |
| if (b == null) { |
| b = load(bTree, patch.getFileName()); |
| } |
| return b.getLine(line - 1); |
| |
| default: |
| throw new NoSuchEntityException(); |
| } |
| } |
| |
| private Text load(final ObjectId tree, final String path) |
| throws MissingObjectException, IncorrectObjectTypeException, |
| CorruptObjectException, IOException { |
| final ObjectId id = DiffCacheContent.find(repo, tree, path); |
| if (id == null) { |
| return Text.EMPTY; |
| } |
| final ObjectLoader ldr = repo.openObject(id); |
| if (ldr == null) { |
| throw new MissingObjectException(id, Constants.TYPE_BLOB); |
| } |
| return new Text(ldr.getCachedBytes()); |
| } |
| |
| private ObjectId emptyTree() throws IOException { |
| return new ObjectWriter(repo).writeCanonicalTree(new byte[0]); |
| } |
| } |