added back a file that I removed
diff --git a/asterix-common/src/main/java/edu/uci/ics/asterix/common/transactions/LogUtil.java b/asterix-common/src/main/java/edu/uci/ics/asterix/common/transactions/LogUtil.java
new file mode 100644
index 0000000..17535e5
--- /dev/null
+++ b/asterix-common/src/main/java/edu/uci/ics/asterix/common/transactions/LogUtil.java
@@ -0,0 +1,136 @@
+/*
+ * Copyright 2009-2013 by The Regents of the University of California
+ * 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 from
+ *
+ * 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 edu.uci.ics.asterix.common.transactions;
+
+import java.io.File;
+import java.io.FilenameFilter;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import edu.uci.ics.asterix.common.exceptions.ACIDException;
+
+/**
+ * A utility class providing helper methods for the {@link ILogManager}
+ */
+public class LogUtil {
+
+ private static final Logger LOGGER = Logger.getLogger(LogUtil.class.getName());
+
+ // read the log directory and initialize log anchor to point to the
+ // current log partition file and the offset where the log manager shall
+ // continue to insert log records.
+
+ public static PhysicalLogLocator initializeLogAnchor(ILogManager logManager) throws ACIDException {
+ int fileId = 0;
+ long offset = 0;
+ LogManagerProperties logManagerProperties = logManager.getLogManagerProperties();
+ File logDir = new File(logManagerProperties.getLogDir());
+ try {
+ if (logDir.exists()) {
+ List<String> logFiles = getLogFiles(logManagerProperties);
+ if (logFiles == null || logFiles.size() == 0) {
+ FileUtil.createFileIfNotExists(getLogFilePath(logManagerProperties, 0));
+ if (LOGGER.isLoggable(Level.INFO)) {
+ LOGGER.info("created a log file: " + getLogFilePath(logManagerProperties, 0));
+ }
+ } else {
+ File logFile = new File(LogUtil.getLogFilePath(logManagerProperties,
+ Long.parseLong(logFiles.get(logFiles.size() - 1))));
+ fileId = logFiles.size() - 1;
+ offset = logFile.length();
+ }
+ } else {
+ FileUtil.createNewDirectory(logManagerProperties.getLogDir());
+ if (LOGGER.isLoggable(Level.INFO)) {
+ LOGGER.info("created the log directory: " + logManagerProperties.getLogDir());
+ }
+ FileUtil.createFileIfNotExists(getLogFilePath(logManagerProperties, 0));
+ if (LOGGER.isLoggable(Level.INFO)) {
+ LOGGER.info("created a log file: " + getLogFilePath(logManagerProperties, 0));
+ }
+ }
+ } catch (IOException ioe) {
+ throw new ACIDException("Unable to initialize log anchor", ioe);
+ }
+ if (LOGGER.isLoggable(Level.INFO)) {
+ LOGGER.info(" file id :" + fileId + " offset " + offset);
+ }
+ return new PhysicalLogLocator(fileId, offset, logManager);
+ }
+
+ public static List<String> getLogFiles(final LogManagerProperties logManagerProperties) {
+ File logDir = new File(logManagerProperties.getLogDir());
+ String[] logFiles = new String[0];
+ List<String> logFileCollection = new ArrayList<String>();
+ if (logDir.exists()) {
+ logFiles = logDir.list(new FilenameFilter() {
+ public boolean accept(File dir, String name) {
+ if (name.startsWith(logManagerProperties.getLogFilePrefix())) {
+ return true;
+ }
+ return false;
+ }
+ });
+ }
+ for (String logFile : logFiles) {
+ logFileCollection.add(logFile.substring(logManagerProperties.getLogFilePrefix().length() + 1));
+ }
+ Collections.sort(logFileCollection, new Comparator<String>() {
+ @Override
+ public int compare(String arg0, String arg1) {
+ return Integer.parseInt(arg0) - Integer.parseInt(arg1);
+ }
+ });
+ return logFileCollection;
+ }
+
+ public static long getFileId(String logFilePath, LogManagerProperties logManagerProperties) {
+ String logFileName = logFilePath;
+ if (logFilePath.contains(File.separator)) {
+ logFileName = logFilePath.substring(logFilePath.lastIndexOf(File.separator));
+ }
+ return Long.parseLong(logFileName.substring(logFileName.indexOf(logManagerProperties.getLogFilePrefix())));
+ }
+
+ public static String getLogFilePath(LogManagerProperties logManagerProperties, long fileId) {
+ return logManagerProperties.getLogDir() + File.separator + logManagerProperties.getLogFilePrefix() + "_"
+ + fileId;
+ }
+
+ public static LogicalLogLocator getDummyLogicalLogLocator(ILogManager logManager) {
+ LogicalLogLocator logicalLogLocator = new LogicalLogLocator(-1, null, -1, logManager);
+ return logicalLogLocator;
+ }
+
+ /*
+ * given a lsn, get the offset within the log file where the corresponding
+ * log record is (to be) placed.
+ */
+ public static long getFileOffset(ILogManager logManager, long lsn) {
+ return lsn % logManager.getLogManagerProperties().getLogPartitionSize();
+ }
+
+ /*
+ * given a lsn, get the file id that contains the log record.
+ */
+ public static long getFileId(ILogManager logManager, long lsn) {
+ return lsn / logManager.getLogManagerProperties().getLogPartitionSize();
+ }
+}
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