Java tutorial
/* * Copyright 2011 Ronald Kurniawan. * * This file is part of CodeTraq. * * CodeTraq is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * CodeTraq is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with CodeTraq. If not, see <http://www.gnu.org/licenses/>. */ package net.mobid.codetraq.runnables; import java.io.File; import java.io.IOException; import java.io.PrintWriter; import java.util.logging.Level; import net.mobid.codetraq.VersionControlChecker; import net.mobid.codetraq.VersionControlType; import net.mobid.codetraq.persistence.ServerDTO; import net.mobid.codetraq.persistence.ServerRevision; import net.mobid.codetraq.persistence.UserDTO; import net.mobid.codetraq.persistence.UserRevision; import net.mobid.codetraq.utils.DbUtility; import net.mobid.codetraq.utils.LogService; import net.mobid.codetraq.utils.Utilities; import org.eclipse.jgit.api.CheckoutCommand; import org.eclipse.jgit.api.CloneCommand; import org.eclipse.jgit.api.Git; import org.eclipse.jgit.api.MergeCommand; import org.eclipse.jgit.api.PullCommand; import org.eclipse.jgit.api.PullResult; import org.eclipse.jgit.lib.ConfigConstants; import org.eclipse.jgit.lib.Constants; import org.eclipse.jgit.lib.ObjectId; import org.eclipse.jgit.lib.ObjectReader; import org.eclipse.jgit.lib.Ref; import org.eclipse.jgit.lib.RefUpdate; import org.eclipse.jgit.lib.Repository; import org.eclipse.jgit.lib.TextProgressMonitor; import org.eclipse.jgit.storage.file.FileRepository; import org.eclipse.jgit.transport.FetchResult; import org.eclipse.jgit.transport.TrackingRefUpdate; /** * This is a worker class whose purpose is to monitor changes on a given git server. * A local repository would be created and the project would be cloned. If a local * repository already exists, then a "pull" is performed. Revision comparison is * then performed locally. * * @author Ronald Kurniawan * @version 0.1 */ public class GitChecker extends VersionControlChecker implements Runnable { private FileRepository repo = null; private Git mGit = null; /** * Creates a new GitChecker. * @param server - a <code>ServerDTO</code> instance * @param user - a <code>UserDTO</code> instance * @param db - a <code>DbUtility</code> instance */ public GitChecker(ServerDTO server, UserDTO user, DbUtility db) { super(server, user, db); } /** * Checks the git repository directory, clone a project if local repository * does not exist, otherwise do a pull to update to latest repository. */ public void run() { // we need to make sure that a project repository dir can be created or // already exists Utilities.createGitProjectDir(_server.getShortName()); File gitProjectDir = new File("gitrepos/" + _server.getShortName()); if (!gitProjectDir.exists()) { System.out.printf( "Cannot create local repositories for server %s. Please check read/write access daemon directory.%n", _server.getServerAddress()); return; } // try to perform clone if it's a fresh repo, otherwise do a pull File dotGitPath = new File("gitrepos/" + _server.getShortName() + "/.git"); if (!dotGitPath.exists()) { clone("gitrepos/" + _server.getShortName()); } else { pull("gitrepos/" + _server.getShortName() + "/.git"); } try { compareLatestRevisionHistory(); } catch (Exception ex) { LogService.getLogger(SvnChecker.class.getName()).log(Level.SEVERE, null, ex); LogService.writeLog(Level.SEVERE, ex); } } /** * Checks if user already has the latest revision on records. If user's version of the revision * is older than the version the server monitor has, we update the user's revision and send * a new message to user. * @return <code>true</code> if user already has latest revision, <code>false</code> * otherwise * @throws Exception */ @Override public boolean compareLatestRevisionHistory() throws Exception { checkServerInUserRecord(); UserRevision ur = _db.getUserLatestRevision(_server.getServerAddress(), _user.getId()); ServerRevision sr = _db.getServerRevisionByAddress(_server.getServerAddress()); if (sr == null) { throw new Exception( "Cannot find server " + _server.getServerAddress() + " in the server revision list."); } if (sr.getVersionControlType() == VersionControlType.GIT) { if (ur.getLastRevisionId() == null || (!ur.getLastRevisionId().equals(sr.getLastRevisionId()))) { LogService.writeMessage( "Updating user revision for " + ur.getServerAddress() + "(owner " + ur.getOwner() + ")"); // update the UserRevision object ur.setLastRevisionId(sr.getLastRevisionId()); _db.updateUserLatestRevision(ur); sendRevisionMessage(sr); return true; } } return false; } /* * Does a pull from a GIT repository. * @param path - path to local repository */ private void pull(String path) { LogService.writeMessage("GitChecker is trying to do a pull from " + _server.getServerAddress()); //System.out.printf("GitChecker is trying to do a pull from %s%n", _server.getServerAddress()); try { File gitDir = new File(path); repo = new FileRepository(gitDir); if (mGit == null) { mGit = new Git(repo); } if (mGit.getRepository().getFullBranch() == null || Utilities.isHexString(mGit.getRepository().getFullBranch())) { attachHead(mGit, _server.getServerBranch()); } PullCommand puller = mGit.pull(); puller.setTimeout(60); puller.setProgressMonitor(new TextProgressMonitor()); PullResult pullResult = puller.call(); if (pullResult != null) { LogService.writeMessage("GitChecker has something to pull from " + _server.getServerAddress()); FetchResult result = pullResult.getFetchResult(); if (result.getTrackingRefUpdates().isEmpty()) { return; } showFetchResult(result, true); } else { LogService.writeMessage( "GitChecker did not find anything to pull from " + _server.getServerAddress()); } } catch (Exception ex) { LogService.getLogger(GitChecker.class.getName()).log(Level.SEVERE, null, ex); LogService.writeLog(Level.SEVERE, ex); } } /* * Clones a GIT repository. * @param path - path to local repository */ private void clone(String path) { LogService.writeMessage("GitChecker is trying to do a clone from " + _server.getServerAddress()); System.out.printf("GitChecker is trying to do a clone from %s%n", _server.getServerAddress()); try { File gitDir = new File(path); CloneCommand cloner = new CloneCommand(); cloner.setBare(false); cloner.setDirectory(gitDir); cloner.setProgressMonitor(new TextProgressMonitor()); cloner.setRemote("origin"); cloner.setURI(_server.getServerAddress()); mGit = cloner.call(); // for some reason, repository cloned with jgit always has HEAD detached. // we need to create a "temporary" branch, then create a "master" branch. // we then merge the two... if (!isMasterBranchDefined(mGit.getRepository())) { // save the remote and merge config values mGit.getRepository().getConfig().setString(ConfigConstants.CONFIG_BRANCH_SECTION, _server.getServerBranch(), ConfigConstants.CONFIG_KEY_REMOTE, "origin"); mGit.getRepository().getConfig().setString(ConfigConstants.CONFIG_BRANCH_SECTION, _server.getServerBranch(), ConfigConstants.CONFIG_KEY_MERGE, _server.getServerBranch()); mGit.getRepository().getConfig().save(); } if (mGit.getRepository().getFullBranch() == null || Utilities.isHexString(mGit.getRepository().getFullBranch())) { // HEAD is detached and we need to reattach it attachHead(mGit, _server.getServerBranch()); } } catch (Exception ex) { LogService.getLogger(GitChecker.class.getName()).log(Level.SEVERE, null, ex); LogService.writeLog(Level.SEVERE, ex); } } /* * Checks whether master branch is defined in local repository's configuration. * @param r - a GIT repository * @return <code>true</code> if master branch is defined, <code>false</code> * otherwise */ private boolean isMasterBranchDefined(Repository r) { if (r.getConfig().getString(ConfigConstants.CONFIG_BRANCH_SECTION, _server.getServerBranch(), ConfigConstants.CONFIG_KEY_REMOTE) == null) { return false; } return true; } /* * Attaches a "detached" HEAD on a local GIT repository. * @param g - a <code>Git</code> object * @param branch - branch name */ private void attachHead(Git g, String branch) { LogService.writeMessage("Trying to attach HEAD to " + g.getRepository().toString()); try { CheckoutCommand temp = g.checkout(); temp.setCreateBranch(true); temp.setName("temp"); Ref tRef = temp.call(); CheckoutCommand b = g.checkout(); b.setName(branch); b.setCreateBranch(true); b.call(); MergeCommand merge = g.merge(); merge.include(tRef); merge.call(); } catch (Exception ex) { LogService.getLogger(GitChecker.class.getName()).log(Level.SEVERE, null, ex); LogService.writeLog(Level.SEVERE, ex); } } /* * This method is borrowed from org.eclipse.jgit.pgm.AbstractFetchCommand and modified to suit our need. */ private void showFetchResult(final FetchResult r, boolean logOnly) { ObjectReader reader = repo.newObjectReader(); PrintWriter out = new PrintWriter(System.out); try { boolean shownURI = false; for (final TrackingRefUpdate u : r.getTrackingRefUpdates()) { if (u.getResult() == RefUpdate.Result.NO_CHANGE) { continue; } final char type = shortTypeOf(u.getResult()); final String longType = longTypeOf(reader, u); final String src = abbreviateRef(u.getRemoteName(), false); final String dst = abbreviateRef(u.getLocalName(), true); if (!shownURI) { out.println("jGIT::from " + r.getURI()); shownURI = true; } if (!logOnly) { out.format(" %c %-17s %-10s -> %s", type, longType, src, dst); out.println(); } } } finally { reader.release(); } showRemoteMessages(r.getMessages()); } /* * This method is borrowed from org.eclipse.jgit.pgm.AbstractFetchCommand and modified to suit our * need. */ static void showRemoteMessages(String pkt) { PrintWriter writer = new PrintWriter(System.err); while (0 < pkt.length()) { final int lf = pkt.indexOf('\n'); final int cr = pkt.indexOf('\r'); final int s; if (0 <= lf && 0 <= cr) s = Math.min(lf, cr); else if (0 <= lf) s = lf; else if (0 <= cr) s = cr; else { writer.print("jGIT::remote reply: " + pkt); writer.println(); break; } if (pkt.charAt(s) == '\r') { writer.print("jGIT::remote reply: " + pkt.substring(0, s)); writer.print('\r'); } else { writer.print("jGIT::remote reply: " + pkt.substring(0, s)); writer.println(); } pkt = pkt.substring(s + 1); } writer.flush(); } /* * This method is borrowed from org.eclipse.jgit.pgm.AbstractFetchCommand. */ private String longTypeOf(ObjectReader reader, final TrackingRefUpdate u) { final RefUpdate.Result r = u.getResult(); if (r == RefUpdate.Result.LOCK_FAILURE) return "[lock fail]"; if (r == RefUpdate.Result.IO_FAILURE) return "[i/o error]"; if (r == RefUpdate.Result.REJECTED) return "[rejected]"; if (ObjectId.zeroId().equals(u.getNewObjectId())) return "[deleted]"; if (r == RefUpdate.Result.NEW) { if (u.getRemoteName().startsWith(Constants.R_HEADS)) return "[new branch]"; else if (u.getLocalName().startsWith(Constants.R_TAGS)) return "[new tag]"; return "[new]"; } if (r == RefUpdate.Result.FORCED) { final String aOld = safeAbbreviate(reader, u.getOldObjectId()); final String aNew = safeAbbreviate(reader, u.getNewObjectId()); return aOld + "..." + aNew; } if (r == RefUpdate.Result.FAST_FORWARD) { final String aOld = safeAbbreviate(reader, u.getOldObjectId()); final String aNew = safeAbbreviate(reader, u.getNewObjectId()); return aOld + ".." + aNew; } if (r == RefUpdate.Result.NO_CHANGE) return "[up to date]"; return "[" + r.name() + "]"; } /* * This method is borrowed from org.eclipse.jgit.pgm.AbstractFetchCommand. */ private String safeAbbreviate(ObjectReader reader, ObjectId id) { try { return reader.abbreviate(id).name(); } catch (IOException cannotAbbreviate) { return id.name(); } } /* * This method is borrowed from org.eclipse.jgit.pgm.AbstractFetchCommand. */ String abbreviateRef(String dst, boolean abbreviateRemote) { if (dst.startsWith(Constants.R_HEADS)) dst = dst.substring(Constants.R_HEADS.length()); else if (dst.startsWith(Constants.R_TAGS)) dst = dst.substring(Constants.R_TAGS.length()); else if (abbreviateRemote && dst.startsWith(Constants.R_REMOTES)) dst = dst.substring(Constants.R_REMOTES.length()); return dst; } /* * This method is borrowed from org.eclipse.jgit.pgm.AbstractFetchCommand. */ private static char shortTypeOf(final RefUpdate.Result r) { if (r == RefUpdate.Result.LOCK_FAILURE) return '!'; if (r == RefUpdate.Result.IO_FAILURE) return '!'; if (r == RefUpdate.Result.NEW) return '*'; if (r == RefUpdate.Result.FORCED) return '+'; if (r == RefUpdate.Result.FAST_FORWARD) return ' '; if (r == RefUpdate.Result.REJECTED) return '!'; if (r == RefUpdate.Result.NO_CHANGE) return '='; return ' '; } }