Added implementation of copyfile rule.

Change-Id: I83e8a3218be2984321342039fda507fdb1aa5f30
Signed-off-by: Yuxuan 'fishy' Wang <fishywang@google.com>

org.eclipse.jgit.test/tst/org/eclipse/jgit/gitrepo/RepoCommandTest.java

 		assertTrue("\"all,-a\" has have b", file.exists());
 	}
 
+	@Test
+	public void testRepoManifestCopyfile() throws Exception {
+		Repository localDb = createWorkRepository();
+		StringBuilder xmlContent = new StringBuilder();
+		xmlContent.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n")
+			.append("<manifest>")
+			.append("<remote name=\"remote1\" fetch=\".\" />")
+			.append("<default revision=\"master\" remote=\"remote1\" />")
+			.append("<project path=\"foo\" name=\"")
+			.append(defaultUri)
+			.append("\">")
+			.append("<copyfile src=\"hello.txt\" dest=\"Hello\" />")
+			.append("</project>")
+			.append("</manifest>");
+		JGitTestUtil.writeTrashFile(localDb, "manifest.xml", xmlContent.toString());
+		RepoCommand command = new RepoCommand(localDb);
+		command.setPath(localDb.getWorkTree().getAbsolutePath() + "/manifest.xml")
+			.setURI(rootUri)
+			.call();
+		// The original file should exist
+		File hello = new File(localDb.getWorkTree(), "foo/hello.txt");
+		assertTrue("The original file exists", hello.exists());
+		BufferedReader reader = new BufferedReader(new FileReader(hello));
+		String content = reader.readLine();
+		reader.close();
+		assertEquals("The original file has expected content", "world", content);
+		// The dest file should also exist
+		hello = new File(localDb.getWorkTree(), "Hello");
+		assertTrue("The destination file exists", hello.exists());
+		reader = new BufferedReader(new FileReader(hello));
+		content = reader.readLine();
+		reader.close();
+		assertEquals("The destination file has expected content", "world", content);
+	}
+
 	private void resolveRelativeUris() {
 		// Find the longest common prefix ends with "/" as rootUri.
 		defaultUri = defaultDb.getDirectory().toURI().toString();

org.eclipse.jgit/resources/org/eclipse/jgit/gitrepo/internal/RepoText.properties

+copyFileFailed=Error occurred during execution of copyfile rule.
 errorNoDefault=Error: no default remote in file {0}.
 errorParsingManifestFile=Error occurred during parsing manifest file {0}.
 invalidManifest=Invalid manifest.

org.eclipse.jgit/src/org/eclipse/jgit/gitrepo/RepoCommand.java

 package org.eclipse.jgit.gitrepo;
 
 import java.io.FileInputStream;
+import java.io.FileOutputStream;
 import java.io.IOException;
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.nio.channels.FileChannel;
 import java.text.MessageFormat;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Map;
 import java.util.Set;
 
+import org.eclipse.jgit.api.AddCommand;
 import org.eclipse.jgit.api.GitCommand;
 import org.eclipse.jgit.api.SubmoduleAddCommand;
 import org.eclipse.jgit.api.errors.GitAPIException;
 
 	private ProgressMonitor monitor;
 
+	private static class CopyFile {
+		final String src;
+		final String dest;
+		final String relativeDest;
+
+		CopyFile(Repository repo, String path, String src, String dest) {
+			this.src = repo.getWorkTree() + "/" + path + "/" + src; //$NON-NLS-1$ //$NON-NLS-2$
+			this.relativeDest = dest;
+			this.dest = repo.getWorkTree() + "/" + dest; //$NON-NLS-1$
+		}
+
+		void copy() throws IOException {
+			FileInputStream input = new FileInputStream(src);
+			try {
+				FileOutputStream output = new FileOutputStream(dest);
+				try {
+					FileChannel channel = input.getChannel();
+					output.getChannel().transferFrom(channel, 0, channel.size());
+				} finally {
+					output.close();
+				}
+			} finally {
+				input.close();
+			}
+		}
+	}
+
 	private static class Project {
 		final String name;
 		final String path;
 		final Set<String> groups;
+		final List<CopyFile> copyfiles;
 
 		Project(String name, String path, String groups) {
 			this.name = name;
 			this.groups = new HashSet<String>();
 			if (groups != null && groups.length() > 0)
 				this.groups.addAll(Arrays.asList(groups.split(","))); //$NON-NLS-1$
+			copyfiles = new ArrayList<CopyFile>();
+		}
+
+		void addCopyFile(CopyFile copyfile) {
+			copyfiles.add(copyfile);
 		}
 	}
 
 		private final Set<String> plusGroups;
 		private final Set<String> minusGroups;
 		private String defaultRemote;
+		private Project currentProject;
 
 		XmlManifest(RepoCommand command, String filename, String baseUrl, String groups) {
 			this.command = command;
 				String qName,
 				Attributes attributes) throws SAXException {
 			if ("project".equals(qName)) { //$NON-NLS-1$
-				projects.add(new Project( //$NON-NLS-1$
-							attributes.getValue("name"), //$NON-NLS-1$
-							attributes.getValue("path"), //$NON-NLS-1$
-							attributes.getValue("groups"))); //$NON-NLS-1$
+				currentProject = new Project( //$NON-NLS-1$
+						attributes.getValue("name"), //$NON-NLS-1$
+						attributes.getValue("path"), //$NON-NLS-1$
+						attributes.getValue("groups")); //$NON-NLS-1$
 			} else if ("remote".equals(qName)) { //$NON-NLS-1$
 				remotes.put(attributes.getValue("name"), //$NON-NLS-1$
 						attributes.getValue("fetch")); //$NON-NLS-1$
 			} else if ("default".equals(qName)) { //$NON-NLS-1$
 				defaultRemote = attributes.getValue("remote"); //$NON-NLS-1$
 			} else if ("copyfile".equals(qName)) { //$NON-NLS-1$
-				// TODO(fishywang): Handle copyfile. Do nothing for now.
+				if (currentProject == null)
+					throw new SAXException(RepoText.get().invalidManifest);
+				currentProject.addCopyFile(new CopyFile(
+							command.repo,
+							currentProject.path,
+							attributes.getValue("src"), //$NON-NLS-1$
+							attributes.getValue("dest"))); //$NON-NLS-1$
+			}
+		}
+
+		@Override
+		public void endElement(
+				String uri,
+				String localName,
+				String qName) throws SAXException {
+			if ("project".equals(qName)) { //$NON-NLS-1$
+				projects.add(currentProject);
+				currentProject = null;
 			}
 		}
 
 				if (inGroups(proj)) {
 					String url = remoteUrl + proj.name;
 					command.addSubmodule(url, proj.path);
+					for (CopyFile copyfile : proj.copyfiles) {
+						try {
+							copyfile.copy();
+						} catch (IOException e) {
+							throw new SAXException(
+									RepoText.get().copyFileFailed, e);
+						}
+						AddCommand add = new AddCommand(command.repo)
+							.addFilepattern(copyfile.relativeDest);
+						try {
+							add.call();
+						} catch (GitAPIException e) {
+							throw new SAXException(e);
+						}
+					}
 				}
 			}
 		}

org.eclipse.jgit/src/org/eclipse/jgit/gitrepo/internal/RepoText.java

 	}
 
 	// @formatter:off
+	/***/ public String copyFileFailed;
 	/***/ public String errorNoDefault;
 	/***/ public String errorParsingManifestFile;
 	/***/ public String invalidManifest;