org.apache.commons.logging.impl.Log4JLogger Java Examples

private void configureAuditLogs() throws IOException {
  // Shutdown the LogManager to release all logger open file handles.
  // Unfortunately, Apache commons logging library does not provide
  // means to release underlying loggers. For additional info look up
  // commons library FAQ.
  LogManager.shutdown();

  File file = new File(auditLogFile);
  if (file.exists()) {
    assertTrue(file.delete());
  }
  Logger logger = ((Log4JLogger) FSNamesystem.auditLog).getLogger();
  // disable logging while the cluster startup preps files
  logger.setLevel(Level.OFF);
  PatternLayout layout = new PatternLayout("%m%n");
  RollingFileAppender appender = new RollingFileAppender(layout, auditLogFile);
  logger.addAppender(appender);
}
 

private void configureAuditLogs() throws IOException {
  // Shutdown the LogManager to release all logger open file handles.
  // Unfortunately, Apache commons logging library does not provide
  // means to release underlying loggers. For additional info look up
  // commons library FAQ.
  LogManager.shutdown();

  File file = new File(auditLogFile);
  if (file.exists()) {
    assertTrue(file.delete());
  }
  Logger logger = ((Log4JLogger) FSNamesystem.auditLog).getLogger();
  // disable logging while the cluster startup preps files
  logger.setLevel(Level.OFF);
  PatternLayout layout = new PatternLayout("%m%n");
  RollingFileAppender appender = new RollingFileAppender(layout, auditLogFile);
  logger.addAppender(appender);
}
 

@Test
public void testLookup() throws Exception
{
    final ConsoleAppender app = new ConsoleAppender(new SimpleLayout());
    final Log log = LogFactory.getLog("TestLogger");
    final Logger logger = ((Log4JLogger)log).getLogger();
    logger.addAppender(app);
    logger.setLevel(Level.DEBUG);
    logger.setAdditivity(false);
    final ExprLookup.Variables vars = new ExprLookup.Variables();
    vars.add(new ExprLookup.Variable("String", org.apache.commons.lang3.StringUtils.class));
    vars.add(new ExprLookup.Variable("Util", new Utility("Hello")));
    vars.add(new ExprLookup.Variable("System", "Class:java.lang.System"));
    final XMLConfiguration config = loadConfig();
    final ConfigurationLogger testLogger = new ConfigurationLogger("TestLogger");
    config.setLogger(testLogger);
    final ExprLookup lookup = new ExprLookup(vars);
    lookup.setInterpolator(config.getInterpolator());
    lookup.setLogger(testLogger);
    String str = lookup.lookup(PATTERN1);
    assertTrue(str.startsWith("Goodbye"));
    str = lookup.lookup(PATTERN2);
    assertTrue("Incorrect value: " + str, str.equals("value Some text"));
    logger.removeAppender(app);
}
 

/**
 * Setup hadoop mini-cluster for test.
 */
private static void oneTimeSetUp() throws IOException {
  ((Log4JLogger)HftpFileSystem.LOG).getLogger().setLevel(Level.ALL);

  final long seed = RAN.nextLong();
  System.out.println("seed=" + seed);
  RAN.setSeed(seed);

  config = new Configuration();
  config.set("slave.host.name", "localhost");

  cluster = new MiniDFSCluster(config, 2, true, null);
  hdfs = cluster.getFileSystem();
  final String hftpuri = "hftp://" + config.get("dfs.http.address");
  System.out.println("hftpuri=" + hftpuri);
  hftpFs = (HftpFileSystem) new Path(hftpuri).getFileSystem(config);
}
 

static String runFsck(Configuration conf, int expectedErrCode,
                      boolean checkErrorCode, String... path)
  throws Exception {
  ByteArrayOutputStream bStream = new ByteArrayOutputStream();
  PrintStream out = new PrintStream(bStream, true);
  ((Log4JLogger) FSPermissionChecker.LOG).getLogger().setLevel(Level.ALL);
  int errCode = ToolRunner.run(new DFSck(conf, out), path);
  if (checkErrorCode) {
    assertEquals(expectedErrCode, errCode);
  }
  ((Log4JLogger) FSPermissionChecker.LOG).getLogger().setLevel(Level.INFO);
  return bStream.toString();
}
 

@Test
public void testPreadDFSNoChecksum() throws IOException {
  Configuration conf = new Configuration();
  ((Log4JLogger)DataTransferProtocol.LOG).getLogger().setLevel(Level.ALL);
  dfsPreadTest(conf, false, false);
  dfsPreadTest(conf, true, false);
}
 

private static void initLoggers() {
  ((Log4JLogger) NameNode.stateChangeLog).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) LogFactory.getLog(FSNamesystem.class)).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) DataNode.LOG).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) TestFiPipelines.LOG).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) DFSClient.LOG).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) FiTestUtil.LOG).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) BlockReceiverAspects.LOG).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) DFSClientAspects.LOG).getLogger().setLevel(Level.ALL);
}
 

/** Sets up log4j logger for auditlogs */
private void setupAuditLogs() throws IOException {
  File file = new File(auditLogFile);
  if (file.exists()) {
    file.delete();
  }
  Logger logger = ((Log4JLogger) FSNamesystem.auditLog).getLogger();
  logger.setLevel(Level.INFO);
  PatternLayout layout = new PatternLayout("%m%n");
  RollingFileAppender appender = new RollingFileAppender(layout, auditLogFile);
  logger.addAppender(appender);
}
 

static String runFsck(Configuration conf, int expectedErrCode, 
                      boolean checkErrorCode,String... path)
                      throws Exception {
  ByteArrayOutputStream bStream = new ByteArrayOutputStream();
  PrintStream out = new PrintStream(bStream, true);
  ((Log4JLogger)FSPermissionChecker.LOG).getLogger().setLevel(Level.ALL);
  int errCode = ToolRunner.run(new DFSck(conf, out), path);
  if (checkErrorCode) {
    assertEquals(expectedErrCode, errCode);
  }
  ((Log4JLogger)FSPermissionChecker.LOG).getLogger().setLevel(Level.INFO);
  FSImage.LOG.error("OUTPUT = " + bStream.toString());
  return bStream.toString();
}
 

private void verifyAuditLogsCheckPattern(boolean expectSuccess, int ndupe, Pattern pattern)
    throws IOException {
  // Turn off the logs
  Logger logger = ((Log4JLogger) FSNamesystem.auditLog).getLogger();
  logger.setLevel(Level.OFF);

  // Close the appenders and force all logs to be flushed
  Enumeration<?> appenders = logger.getAllAppenders();
  while (appenders.hasMoreElements()) {
    Appender appender = (Appender)appenders.nextElement();
    appender.close();
  }

  BufferedReader reader = new BufferedReader(new FileReader(auditLogFile));
  String line = null;
  boolean ret = true;
  boolean patternMatches = false;

  try {
      for (int i = 0; i < ndupe; i++) {
        line = reader.readLine();
        assertNotNull(line);
        patternMatches |= pattern.matcher(line).matches();
        ret &= successPattern.matcher(line).matches();
      }
      assertNull("Unexpected event in audit log", reader.readLine());
      assertTrue("Expected audit event not found in audit log", patternMatches);
      assertTrue("Expected success=" + expectSuccess, ret == expectSuccess);
    } finally {
      reader.close();
    }
}
 

private void verifyAuditLogsRepeat(boolean expectSuccess, int ndupe)
    throws IOException {
  // Turn off the logs
  Logger logger = ((Log4JLogger) FSNamesystem.auditLog).getLogger();
  logger.setLevel(Level.OFF);

  // Close the appenders and force all logs to be flushed
  Enumeration<?> appenders = logger.getAllAppenders();
  while (appenders.hasMoreElements()) {
    Appender appender = (Appender)appenders.nextElement();
    appender.close();
  }

  BufferedReader reader = new BufferedReader(new FileReader(auditLogFile));
  String line = null;
  boolean ret = true;

  try {
    for (int i = 0; i < ndupe; i++) {
      line = reader.readLine();
      assertNotNull(line);
      assertTrue("Expected audit event not found in audit log",
          auditPattern.matcher(line).matches());
      ret &= successPattern.matcher(line).matches();
    }
    assertNull("Unexpected event in audit log", reader.readLine());
    assertTrue("Expected success=" + expectSuccess, ret == expectSuccess);
  } finally {
    reader.close();
  }
}
 

@Before
 public void setupCluster() throws Exception {
   // must configure prior to instantiating the namesystem because it
   // will reconfigure the logger if async is enabled
   configureAuditLogs();
   conf = new HdfsConfiguration();
   final long precision = 1L;
   conf.setLong(DFSConfigKeys.DFS_NAMENODE_ACCESSTIME_PRECISION_KEY, precision);
   conf.setLong(DFSConfigKeys.DFS_BLOCKREPORT_INTERVAL_MSEC_KEY, 10000L);
   conf.setBoolean(DFSConfigKeys.DFS_WEBHDFS_ENABLED_KEY, true);
   conf.setBoolean(DFSConfigKeys.DFS_NAMENODE_AUDIT_LOG_ASYNC_KEY, useAsyncLog);
   util = new DFSTestUtil.Builder().setName("TestAuditAllowed").
       setNumFiles(20).build();
   cluster = new MiniDFSCluster.Builder(conf).numDataNodes(4).build();
   fs = cluster.getFileSystem();
   util.createFiles(fs, fileName);

   // make sure the appender is what it's supposed to be
   Logger logger = ((Log4JLogger) FSNamesystem.auditLog).getLogger();
   @SuppressWarnings("unchecked")
   List<Appender> appenders = Collections.list(logger.getAllAppenders());
   assertEquals(1, appenders.size());
   assertEquals(useAsyncLog, appenders.get(0) instanceof AsyncAppender);
   
   fnames = util.getFileNames(fileName);
   util.waitReplication(fs, fileName, (short)3);
   userGroupInfo = UserGroupInformation.createUserForTesting(username, groups);
}
 

@SuppressWarnings("deprecation")
@Test
public void testDelegationTokenWebHdfsApi() throws Exception {
  ((Log4JLogger)NamenodeWebHdfsMethods.LOG).getLogger().setLevel(Level.ALL);
  final String uri = WebHdfsFileSystem.SCHEME  + "://"
      + config.get(DFSConfigKeys.DFS_NAMENODE_HTTP_ADDRESS_KEY);
  //get file system as JobTracker
  final UserGroupInformation ugi = UserGroupInformation.createUserForTesting(
      "JobTracker", new String[]{"user"});
  final WebHdfsFileSystem webhdfs = ugi.doAs(
      new PrivilegedExceptionAction<WebHdfsFileSystem>() {
    @Override
    public WebHdfsFileSystem run() throws Exception {
      return (WebHdfsFileSystem)FileSystem.get(new URI(uri), config);
    }
  });

  { //test addDelegationTokens(..)
    Credentials creds = new Credentials();
    final Token<?> tokens[] = webhdfs.addDelegationTokens("JobTracker", creds);
    Assert.assertEquals(1, tokens.length);
    Assert.assertEquals(1, creds.numberOfTokens());
    Assert.assertSame(tokens[0], creds.getAllTokens().iterator().next());
    checkTokenIdentifier(ugi, tokens[0]);
    final Token<?> tokens2[] = webhdfs.addDelegationTokens("JobTracker", creds);
    Assert.assertEquals(0, tokens2.length);
  }
}
 

/** Test client retry with namenode restarting. */
@Test(timeout=300000)
public void testNamenodeRestart() throws Exception {
  ((Log4JLogger)NamenodeWebHdfsMethods.LOG).getLogger().setLevel(Level.ALL);
  final Configuration conf = WebHdfsTestUtil.createConf();
  TestDFSClientRetries.namenodeRestartTest(conf, true);
}
 

static void turnOffNameNodeLogging() {
  // change log level to ERROR: NameNode.LOG & NameNode.stateChangeLog
  ((Log4JLogger)NameNode.LOG).getLogger().setLevel(Level.ERROR);
  ((Log4JLogger)NameNode.stateChangeLog).getLogger().setLevel(Level.ERROR);
  ((Log4JLogger)NetworkTopology.LOG).getLogger().setLevel(Level.ERROR);
  ((Log4JLogger)FSNamesystem.LOG).getLogger().setLevel(Level.ERROR);
  ((Log4JLogger)FSNamesystem.auditLog).getLogger().setLevel(Level.ERROR);
  ((Log4JLogger)LeaseManager.LOG).getLogger().setLevel(Level.ERROR);
}
 

private static void initLoggers() {
  ((Log4JLogger) NameNode.stateChangeLog).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) LogFactory.getLog(FSNamesystem.class)).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) DataNode.LOG).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) TestFiPipelines.LOG).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) DFSClient.LOG).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) FiTestUtil.LOG).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) BlockReceiverAspects.LOG).getLogger().setLevel(Level.ALL);
  ((Log4JLogger) DFSClientAspects.LOG).getLogger().setLevel(Level.ALL);
}
 

@Test
public void testPreadDFSNoChecksum() throws IOException {
  Configuration conf = new Configuration();
  ((Log4JLogger)DataTransferProtocol.LOG).getLogger().setLevel(Level.ALL);
  dfsPreadTest(conf, false, false);
  dfsPreadTest(conf, true, false);
}
 

static void turnOffNameNodeLogging() {
  // change log level to ERROR: NameNode.LOG & NameNode.stateChangeLog
  ((Log4JLogger)NameNode.LOG).getLogger().setLevel(Level.ERROR);
  ((Log4JLogger)NameNode.stateChangeLog).getLogger().setLevel(Level.ERROR);
  ((Log4JLogger)NetworkTopology.LOG).getLogger().setLevel(Level.ERROR);
  ((Log4JLogger)FSNamesystem.LOG).getLogger().setLevel(Level.ERROR);
  ((Log4JLogger)FSNamesystem.auditLog).getLogger().setLevel(Level.ERROR);
  ((Log4JLogger)LeaseManager.LOG).getLogger().setLevel(Level.ERROR);
}
 

static void turnOffNameNodeLogging() {
	// change log level to ERROR: NameNode.LOG & NameNode.stateChangeLog
	((Log4JLogger) NameNode.LOG).getLogger().setLevel(Level.ERROR);
	((Log4JLogger) NameNode.stateChangeLog).getLogger().setLevel(
			Level.ERROR);
	((Log4JLogger) NetworkTopology.LOG).getLogger().setLevel(Level.ERROR);
	((Log4JLogger) FSNamesystem.LOG).getLogger().setLevel(Level.ERROR);
	((Log4JLogger) FSNamesystem.auditLog).getLogger().setLevel(Level.ERROR);
	((Log4JLogger) LeaseManager.LOG).getLogger().setLevel(Level.ERROR);
}
 

/** Test client retry with namenode restarting. */
@Test(timeout=300000)
public void testNamenodeRestart() throws Exception {
  ((Log4JLogger)NamenodeWebHdfsMethods.LOG).getLogger().setLevel(Level.ALL);
  final Configuration conf = WebHdfsTestUtil.createConf();
  TestDFSClientRetries.namenodeRestartTest(conf, true);
}
 

@SuppressWarnings("deprecation")
@Test
public void testDelegationTokenWebHdfsApi() throws Exception {
  ((Log4JLogger)NamenodeWebHdfsMethods.LOG).getLogger().setLevel(Level.ALL);
  final String uri = WebHdfsFileSystem.SCHEME  + "://"
      + config.get(DFSConfigKeys.DFS_NAMENODE_HTTP_ADDRESS_KEY);
  //get file system as JobTracker
  final UserGroupInformation ugi = UserGroupInformation.createUserForTesting(
      "JobTracker", new String[]{"user"});
  final WebHdfsFileSystem webhdfs = ugi.doAs(
      new PrivilegedExceptionAction<WebHdfsFileSystem>() {
    @Override
    public WebHdfsFileSystem run() throws Exception {
      return (WebHdfsFileSystem)FileSystem.get(new URI(uri), config);
    }
  });

  { //test addDelegationTokens(..)
    Credentials creds = new Credentials();
    final Token<?> tokens[] = webhdfs.addDelegationTokens("JobTracker", creds);
    Assert.assertEquals(1, tokens.length);
    Assert.assertEquals(1, creds.numberOfTokens());
    Assert.assertSame(tokens[0], creds.getAllTokens().iterator().next());
    checkTokenIdentifier(ugi, tokens[0]);
    final Token<?> tokens2[] = webhdfs.addDelegationTokens("JobTracker", creds);
    Assert.assertEquals(0, tokens2.length);
  }
}
 

@Before
 public void setupCluster() throws Exception {
   // must configure prior to instantiating the namesystem because it
   // will reconfigure the logger if async is enabled
   configureAuditLogs();
   conf = new HdfsConfiguration();
   final long precision = 1L;
   conf.setLong(DFSConfigKeys.DFS_NAMENODE_ACCESSTIME_PRECISION_KEY, precision);
   conf.setLong(DFSConfigKeys.DFS_BLOCKREPORT_INTERVAL_MSEC_KEY, 10000L);
   conf.setBoolean(DFSConfigKeys.DFS_WEBHDFS_ENABLED_KEY, true);
   conf.setBoolean(DFSConfigKeys.DFS_NAMENODE_AUDIT_LOG_ASYNC_KEY, useAsyncLog);
   util = new DFSTestUtil.Builder().setName("TestAuditAllowed").
       setNumFiles(20).build();
   cluster = new MiniDFSCluster.Builder(conf).numDataNodes(4).build();
   fs = cluster.getFileSystem();
   util.createFiles(fs, fileName);

   // make sure the appender is what it's supposed to be
   Logger logger = ((Log4JLogger) FSNamesystem.auditLog).getLogger();
   @SuppressWarnings("unchecked")
   List<Appender> appenders = Collections.list(logger.getAllAppenders());
   assertEquals(1, appenders.size());
   assertEquals(useAsyncLog, appenders.get(0) instanceof AsyncAppender);
   
   fnames = util.getFileNames(fileName);
   util.waitReplication(fs, fileName, (short)3);
   userGroupInfo = UserGroupInformation.createUserForTesting(username, groups);
}
 

static String runFsck(Configuration conf, int expectedErrCode, 
                      boolean checkErrorCode,String... path) 
                      throws Exception {
  PrintStream oldOut = System.out;
  ByteArrayOutputStream bStream = new ByteArrayOutputStream();
  PrintStream newOut = new PrintStream(bStream, true);
  System.setOut(newOut);
  ((Log4JLogger)PermissionChecker.LOG).getLogger().setLevel(Level.ALL);
  int errCode = ToolRunner.run(new DFSck(conf), path);
  if (checkErrorCode)
    assertEquals(expectedErrCode, errCode);
  ((Log4JLogger)PermissionChecker.LOG).getLogger().setLevel(Level.INFO);
  System.setOut(oldOut);
  return bStream.toString();
}
 

/** Sets up log4j logger for auditlogs */
private void setupAuditLogs() throws IOException {
  File file = new File(auditLogFile);
  if (file.exists()) {
    file.delete();
  }
  Logger logger = ((Log4JLogger) FSNamesystem.auditLog).getLogger();
  logger.setLevel(Level.INFO);
  PatternLayout layout = new PatternLayout("%m%n");
  RollingFileAppender appender = new RollingFileAppender(layout, auditLogFile);
  logger.addAppender(appender);
}
 

static String runFsck(Configuration conf, int expectedErrCode, 
                      boolean checkErrorCode,String... path)
                      throws Exception {
  ByteArrayOutputStream bStream = new ByteArrayOutputStream();
  PrintStream out = new PrintStream(bStream, true);
  ((Log4JLogger)FSPermissionChecker.LOG).getLogger().setLevel(Level.ALL);
  int errCode = ToolRunner.run(new DFSck(conf, out), path);
  if (checkErrorCode) {
    assertEquals(expectedErrCode, errCode);
  }
  ((Log4JLogger)FSPermissionChecker.LOG).getLogger().setLevel(Level.INFO);
  FSImage.LOG.error("OUTPUT = " + bStream.toString());
  return bStream.toString();
}
 

private void verifyAuditLogsCheckPattern(boolean expectSuccess, int ndupe, Pattern pattern)
    throws IOException {
  // Turn off the logs
  Logger logger = ((Log4JLogger) FSNamesystem.auditLog).getLogger();
  logger.setLevel(Level.OFF);

  // Close the appenders and force all logs to be flushed
  Enumeration<?> appenders = logger.getAllAppenders();
  while (appenders.hasMoreElements()) {
    Appender appender = (Appender)appenders.nextElement();
    appender.close();
  }

  BufferedReader reader = new BufferedReader(new FileReader(auditLogFile));
  String line = null;
  boolean ret = true;
  boolean patternMatches = false;

  try {
      for (int i = 0; i < ndupe; i++) {
        line = reader.readLine();
        assertNotNull(line);
        patternMatches |= pattern.matcher(line).matches();
        ret &= successPattern.matcher(line).matches();
      }
      assertNull("Unexpected event in audit log", reader.readLine());
      assertTrue("Expected audit event not found in audit log", patternMatches);
      assertTrue("Expected success=" + expectSuccess, ret == expectSuccess);
    } finally {
      reader.close();
    }
}
 

private void verifyAuditLogsRepeat(boolean expectSuccess, int ndupe)
    throws IOException {
  // Turn off the logs
  Logger logger = ((Log4JLogger) FSNamesystem.auditLog).getLogger();
  logger.setLevel(Level.OFF);

  // Close the appenders and force all logs to be flushed
  Enumeration<?> appenders = logger.getAllAppenders();
  while (appenders.hasMoreElements()) {
    Appender appender = (Appender)appenders.nextElement();
    appender.close();
  }

  BufferedReader reader = new BufferedReader(new FileReader(auditLogFile));
  String line = null;
  boolean ret = true;

  try {
    for (int i = 0; i < ndupe; i++) {
      line = reader.readLine();
      assertNotNull(line);
      assertTrue("Expected audit event not found in audit log",
          auditPattern.matcher(line).matches());
      ret &= successPattern.matcher(line).matches();
    }
    assertNull("Unexpected event in audit log", reader.readLine());
    assertTrue("Expected success=" + expectSuccess, ret == expectSuccess);
  } finally {
    reader.close();
  }
}
 

public static LogCapturer captureLogs(Log l) {
  Logger logger = ((Log4JLogger) l).getLogger();
  return new LogCapturer(logger);
}
 

public static RequestLog getRequestLog(String name) {

    String lookup = serverToComponent.get(name);
    if (lookup != null) {
      name = lookup;
    }
    String loggerName = "http.requests." + name;
    String appenderName = name + "requestlog";
    Log logger = LogFactory.getLog(loggerName);

    boolean isLog4JLogger;;
    try {
      isLog4JLogger = logger instanceof Log4JLogger;
    } catch (NoClassDefFoundError err) {
      // In some dependent projects, log4j may not even be on the classpath at
      // runtime, in which case the above instanceof check will throw
      // NoClassDefFoundError.
      LOG.debug("Could not load Log4JLogger class", err);
      isLog4JLogger = false;
    }
    if (isLog4JLogger) {
      Log4JLogger httpLog4JLog = (Log4JLogger)logger;
      Logger httpLogger = httpLog4JLog.getLogger();
      Appender appender = null;

      try {
        appender = httpLogger.getAppender(appenderName);
      } catch (LogConfigurationException e) {
        LOG.warn("Http request log for " + loggerName
            + " could not be created");
        throw e;
      }

      if (appender == null) {
        LOG.info("Http request log for " + loggerName
            + " is not defined");
        return null;
      }

      if (appender instanceof HttpRequestLogAppender) {
        HttpRequestLogAppender requestLogAppender
          = (HttpRequestLogAppender)appender;
        NCSARequestLog requestLog = new NCSARequestLog();
        requestLog.setFilename(requestLogAppender.getFilename());
        requestLog.setRetainDays(requestLogAppender.getRetainDays());
        return requestLog;
      }
      else {
        LOG.warn("Jetty request log for " + loggerName
            + " was of the wrong class");
        return null;
      }
    }
    else {
      LOG.warn("Jetty request log can only be enabled using Log4j");
      return null;
    }
  }
 

@SuppressWarnings("unchecked")
public static void disableLog(Log log) {
  // We expect that commons-logging is a wrapper around Log4j.
  disableLog((Log4JLogger) log);
}