opengrok/history/HistoryGuru.java

	HistoryGuru.java revision 5a0c5ad4116f5a4dd0dd5a0a4e6d02973cd5eef9
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic/*
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d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic/*
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
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d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic */
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republicpackage org.opensolaris.opengrok.history;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republicimport java.io.File;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republicimport java.io.IOException;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republicimport java.io.InputStream;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republicimport java.util.ArrayList;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republicimport java.util.HashMap;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republicimport java.util.List;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republicimport java.util.Map;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republicimport java.util.logging.Level;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republicimport org.opensolaris.opengrok.OpenGrokLogger;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republicimport org.opensolaris.opengrok.configuration.RuntimeEnvironment;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republicimport org.opensolaris.opengrok.index.IgnoredNames;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic/**
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic * The HistoryGuru is used to implement an transparent layer to the various
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic * source control systems.
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic *
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic * @author Chandan
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic */
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republicpublic final class HistoryGuru {
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    /** The one and only instance of the HistoryGuru */
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    private static HistoryGuru instance = new HistoryGuru();
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    /** The history cache to use */
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    private final HistoryCache historyCache;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    /**
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     * Creates a new instance of HistoryGuru, and try to set the default
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     * source control system.
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     */
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    private HistoryGuru() {
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic        historyCache = new FileHistoryCache();
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    }
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    /**
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     * Get the one and only instance of the HistoryGuru
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     * @return the one and only HistoryGuru instance
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     */
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    public static HistoryGuru getInstance()  {
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic        return instance;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    }
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    /**
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     * Get the <code>HistoryParser</code> to use for the specified file.
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     */
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    private Class<? extends HistoryParser> getHistoryParser(File file) {
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic        Repository repos = getRepository(file.getParentFile());
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic        if (repos != null && repos.fileHasHistory(file)) {
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic            Class<? extends HistoryParser> parser;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic            parser = repos.getHistoryParser();
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic            if (parser != null) {
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic                return parser;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic            }
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic        }
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic        return null;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    }
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    /**
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     * Annotate the specified revision of a file.
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     *
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     * @param file the file to annotate
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     * @param rev the revision to annotate (<code>null</code> means BASE)
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     * @return file annotation, or <code>null</code> if the
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     * <code>HistoryParser</code> does not support annotation
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     */
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    public Annotation annotate(File file, String rev) throws IOException {
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic        Repository repos = getRepository(file);
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic        if (repos != null) {
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic            return repos.annotate(file, rev);
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic        }
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic        return null;
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    }
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic    /**
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     * Get the appropriate history reader for the file specified by parent and basename.
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     *
d3f4f9ed01f6a0b171d0a81c630f5708e47adb7avitezslav batrla - Sun Microsystems - Prague Czech Republic     * @param file The file to get the history reader for
     * @throws java.io.IOException If an error occurs while trying to access the filesystem
     * @return A HistorReader that may be used to read out history data for a named file
     */
    @SuppressWarnings("PMD.AvoidRethrowingException")
    public HistoryReader getHistoryReader(File file) throws IOException {
        if (file.isDirectory()) {
            return getDirectoryHistoryReader(file);
        }

        Class<? extends HistoryParser> parser = getHistoryParser(file);

        if (parser != null) {
            try {
                Repository repos = getRepository(file.getParentFile());
                History history = historyCache.get(file, repos);
                if (history == null) {
                    return null;
                }
                return new HistoryReader(history);
            } catch (Exception e) {
                throw new IOException("Error while constructing HistoryReader "+ e.getMessage());
            }
        }

        return null;
    }

    /**
     * Get the appropriate history reader for a specific directory.
     *
     * @param file The directpru to get the history reader for
     * @throws java.io.IOException If an error occurs while trying to access the filesystem
     * @return A HistorReader that may be used to read out history data for a named file
     */
    @SuppressWarnings("PMD.AvoidRethrowingException")
    private HistoryReader getDirectoryHistoryReader(File file) throws IOException {
        Class<? extends HistoryParser> parser = null;
        Repository repos = getRepository(file);
        if (repos != null) {
            parser = repos.getDirectoryHistoryParser();
        }

        if (parser == null) {
            // I did not find a match for the specified system. Use the default directory reader
            parser = DirectoryHistoryParser.class;
            repos = null;
        }

        if (parser != null) {
            try {
                History history = historyCache.get(file, repos);
                if (history != null) {
                    return new HistoryReader(history);
                }
            } catch (IOException ioe) {
                throw ioe;
            } catch (Exception e) {
                throw new IOException("Error while constructing HistoryReader "+ e.getMessage());
            }
        }

        return null;
    }

    /**
     * Get a named revision of the specified file.
     * @param parent The directory containing the file
     * @param basename The name of the file
     * @param rev The revision to get
     * @throws java.io.IOException If an error occurs while reading out the version
     * @return An InputStream containing the named revision of the file.
     */
    public InputStream getRevision(String parent, String basename, String rev) throws IOException {
        Repository rep = getRepository(new File(parent));
        if (rep != null) {
            return rep.getHistoryGet(parent, basename, rev);
        }
        return null;
    }

    /**
     * Does this directory contain files with source control information?
     * @param file The name of the directory
     * @return true if the files in this directory have associated revision history
     */
    public boolean hasHistory(File file) {
        Repository repos = getRepository(file);
        return repos != null && repos.isWorking() && repos.fileHasHistory(file);
    }

    /**
     * Check if we can annotate the specified file.
     *
     * @param file the file to check
     * @return <code>true</code> if the file is under version control and the
     * version control system supports annotation
     */
    public boolean hasAnnotation(File file) {
        if (!file.isDirectory()) {
            Repository repos = getRepository(file);
            if (repos != null && repos.isWorking()) {
                return repos.fileHasAnnotation(file);
            }
        }

        return false;
    }

    private void addRepositories(File[] files, Map<String, Repository> repos,
            IgnoredNames ignoredNames) {
        addRepositories(files, repos, ignoredNames, true);
    }

    @SuppressWarnings("PMD.ConfusingTernary")
    private void addRepositories(File[] files, Map<String, Repository> repos,
            IgnoredNames ignoredNames, boolean recursiveSearch) {

        if (files == null) {
            return;
        }

        for (File file : files) {
            Repository repository = null;
            try {
                repository = RepositoryFactory.getRepository(file);
            } catch (InstantiationException ie) {
                OpenGrokLogger.getLogger().log(Level.WARNING, "Could not create repoitory for '" + file + "', could not instantiate the repository.", ie);
            } catch (IllegalAccessException iae) {
                OpenGrokLogger.getLogger().log(Level.WARNING, "Could not create repoitory for '" + file + "', missing access rights.", iae);
            }
            if (repository != null) {
                try {
                    String path = file.getCanonicalPath();
                    repository.setDirectoryName(path);
                    if (RuntimeEnvironment.getInstance().isVerbose()) {
                        OpenGrokLogger.getLogger().log(Level.INFO, "Adding <" + repository.getClass().getName() +  "> repository: <" + path + ">");
                    }
                    addRepository(repository, path, repos);

                    // @TODO: Search only for one type of repository - the one found here
                    if (recursiveSearch && repository.supportsSubRepositories()) {
                        File subFiles[] = file.listFiles();
                        if (subFiles == null) {
                            OpenGrokLogger.getLogger().log(Level.WARNING, "Failed to get sub directories for '" + file.getAbsolutePath() + "', check access permissions.");
                        } else {
                            // Search only one level down - if not: too much stat'ing for huge Mercurial repositories
                            addRepositories(subFiles, repos, ignoredNames, false);
                        }
                    }

                } catch (IOException exp) {
                    OpenGrokLogger.getLogger().log(Level.WARNING, "Failed to get canonical path for " + file.getAbsolutePath() + ": " + exp.getMessage());
                    OpenGrokLogger.getLogger().log(Level.WARNING, "Repository will be ignored...", exp);
                }
            } else {
                // Not a repository, search it's sub-dirs
                if (file.isDirectory() && !ignoredNames.ignore(file)) {
                    File subFiles[] = file.listFiles();
                    if (subFiles == null) {
                        OpenGrokLogger.getLogger().log(Level.WARNING, "Failed to get sub directories for '" + file.getAbsolutePath() + "', check access permissions.");
                    } else {
                        addRepositories(subFiles, repos, ignoredNames);
                    }
                }
            }
        }
    }

    private void addRepository(Repository rep, String path, Map<String, Repository> repos) {
        repos.put(path, rep);
    }

    /**
     * Search through the all of the directories and add all of the source
     * repositories found.
     *
     * @param dir the root directory to start the search in.
     */
    public void addRepositories(String dir) {
        Map<String, Repository> repos = new HashMap<String, Repository>();
        addRepositories(new File[] {new File(dir)}, repos,
                RuntimeEnvironment.getInstance().getIgnoredNames());
        RuntimeEnvironment.getInstance().setRepositories(repos);
    }

    /**
     * Update the source the contents in the source repositories.
     */
    public void updateRepositories() {
        boolean verbose = RuntimeEnvironment.getInstance().isVerbose();

        for (Map.Entry<String, Repository> entry : RuntimeEnvironment.getInstance().getRepositories().entrySet()) {
            Repository repository = entry.getValue();

            String path = entry.getKey();
            String type = repository.getClass().getSimpleName();

            if (verbose) {
                OpenGrokLogger.getLogger().log(Level.INFO, "Update " + type + " repository in " + path);
            }

            try {
                repository.update();
            } catch (Exception e) {
                OpenGrokLogger.getLogger().log(Level.WARNING, "An error occured while updating " + path + " (" + type + ")", e);
            }
        }
    }

    private void createCache(Repository repository) {
        boolean verbose = RuntimeEnvironment.getInstance().isVerbose();
        String path = repository.getDirectoryName();
        String type = repository.getClass().getSimpleName();
        long start = System.currentTimeMillis();

        if (verbose) {
            OpenGrokLogger.getLogger().log(Level.INFO, "Create historycache for " + path + " (" + type + ")");
        }

        try {
            repository.createCache(historyCache);
        } catch (Exception e) {
            OpenGrokLogger.getLogger().log(Level.WARNING, "An error occured while creating cache for " + path + " (" + type + ")", e);
        }
        long stop = System.currentTimeMillis();
        if (verbose) {
            OpenGrokLogger.getLogger().log(Level.INFO, "Creating historycache for " + path + " took (" + (stop - start) + "ms)");
        }
    }

    /**
     * Create the history cache for all of the repositories
     */
    public void createCache() {
        boolean threading = System.getProperty("org.opensolaris.opengrok.history.threads", null) != null;
        ArrayList<Thread> threads = new ArrayList<Thread>();

        for (Map.Entry<String, Repository> entry : RuntimeEnvironment.getInstance().getRepositories().entrySet()) {
            if (threading) {
                final Repository repos = entry.getValue();
                Thread t = new Thread(new Runnable() {
                    public void run() {
                        createCache(repos);
                    }
                });
                t.start();
                threads.add(t);
            } else {
                createCache(entry.getValue());
            }
        }
        // Wait for all threads to finish
        while (!threads.isEmpty()) {
            for (Thread t : threads) {
                if (!t.isAlive()) {
                    try {
                        t.join();
                        threads.remove(t);
                        break;
                    } catch (InterruptedException ex) {
                    }
                }
            }
            try {
                Thread.sleep(1000);
            } catch (Exception e) {
                OpenGrokLogger.getLogger().log(Level.INFO, "Woken up during sleep for threads to finish", e);
            }
        }
    }

    public void createCache(List<String> repositories) {
        boolean threading = System.getProperty("org.opensolaris.opengrok.history.threads", null) != null;
        ArrayList<Thread> threads = new ArrayList<Thread>();
        File root = RuntimeEnvironment.getInstance().getSourceRootFile();
        for (String file : repositories) {
            final Repository repos = getRepository(new File(root, file));
            if (repos != null) {
                if (threading) {
                    Thread t = new Thread(new Runnable() {
                        public void run() {
                            createCache(repos);
                        }
                    });
                    t.start();
                    threads.add(t);
                } else {
                    createCache(repos);
                }
            }
        }

        // Wait for all threads to finish
        while (!threads.isEmpty()) {
            for (Thread t : threads) {
                if (!t.isAlive()) {
                    try {
                        t.join();
                        threads.remove(t);
                        break;
                    } catch (InterruptedException ex) {
                    }
                }
            }
            try {
                Thread.sleep(1000);
            } catch (Exception e) {
                OpenGrokLogger.getLogger().log(Level.INFO, "Woken up during sleep for threads to finish", e);
            }
        }
    }


    private Repository getRepository(File path) {
        Map<String, Repository> repos = RuntimeEnvironment.getInstance().getRepositories();

        File canonicalPath = path;
        try {
            canonicalPath = path.getCanonicalFile();
        } catch (IOException e) {
            OpenGrokLogger.getLogger().log(Level.WARNING, "Failed to get canonical path for " + path, e);
            return null;
        }
        while (canonicalPath != null) {
            try {
                Repository r = repos.get(canonicalPath.getCanonicalPath());
                if (r != null) {
                    return r;
                }
            } catch (IOException e) {
                OpenGrokLogger.getLogger().log(Level.WARNING, "Failed to get canonical path for " + canonicalPath, e);
            }
            canonicalPath = canonicalPath.getParentFile();
        }

        return null;
    }
}