Java 类org.apache.hadoop.hbase.regionserver.wal.ProtobufLogWriter 实例源码

/**
 * public because of FSHLog. Should be package-private
 */
public static Writer createWriter(final Configuration conf, final FileSystem fs, final Path path,
    final boolean overwritable)
    throws IOException {
  // Configuration already does caching for the Class lookup.
  Class<? extends Writer> logWriterClass = conf.getClass("hbase.regionserver.hlog.writer.impl",
      ProtobufLogWriter.class, Writer.class);
  try {
    Writer writer = logWriterClass.newInstance();
    writer.init(fs, path, conf, overwritable);
    return writer;
  } catch (Exception e) {
    LOG.debug("Error instantiating log writer.", e);
    throw new IOException("cannot get log writer", e);
  }
}

@Override
protected Writer createWriterInstance(final Path path) throws IOException {
  // we get called from the FSHLog constructor (!); always roll in this case since
  // we don't know yet if we're supposed to generally roll and
  // we need an initial file in the case of doing appends but no rolls.
  if (!initialized || doFileRolls) {
    LOG.info("creating new writer instance.");
    final ProtobufLogWriter writer = new IOTestWriter();
    writer.init(fs, path, conf, false);
    if (!initialized) {
      LOG.info("storing initial writer instance in case file rolling isn't allowed.");
      noRollsWriter = writer;
    }
    return writer;
  } else {
    LOG.info("WAL rolling disabled, returning the first writer.");
    // Initial assignment happens during the constructor call, so there ought not be
    // a race for first assignment.
    return noRollsWriter;
  }
}

/**
 * public because of FSHLog. Should be package-private
 */
public static Writer createWriter(final Configuration conf, final FileSystem fs, final Path path,
    final boolean overwritable)
    throws IOException {
  // Configuration already does caching for the Class lookup.
  Class<? extends Writer> logWriterClass = conf.getClass("hbase.regionserver.hlog.writer.impl",
      ProtobufLogWriter.class, Writer.class);
  try {
    Writer writer = logWriterClass.newInstance();
    writer.init(fs, path, conf, overwritable);
    return writer;
  } catch (Exception e) {
    LOG.debug("Error instantiating log writer.", e);
    throw new IOException("cannot get log writer", e);
  }
}

@Override
protected Writer createWriterInstance(final Path path) throws IOException {
  // we get called from the FSHLog constructor (!); always roll in this case since
  // we don't know yet if we're supposed to generally roll and
  // we need an initial file in the case of doing appends but no rolls.
  if (!initialized || doFileRolls) {
    LOG.info("creating new writer instance.");
    final ProtobufLogWriter writer = new IOTestWriter();
    writer.init(fs, path, conf, false);
    if (!initialized) {
      LOG.info("storing initial writer instance in case file rolling isn't allowed.");
      noRollsWriter = writer;
    }
    return writer;
  } else {
    LOG.info("WAL rolling disabled, returning the first writer.");
    // Initial assignment happens during the constructor call, so there ought not be
    // a race for first assignment.
    return noRollsWriter;
  }
}

@Override
protected Writer createWriterInstance(final Path path) throws IOException {
  // we get called from the FSHLog constructor (!); always roll in this case since
  // we don't know yet if we're supposed to generally roll and
  // we need an initial file in the case of doing appends but no rolls.
  if (!initialized || doFileRolls) {
    LOG.info("creating new writer instance.");
    final ProtobufLogWriter writer = new IOTestWriter();
    try {
      writer.init(fs, path, conf, false);
    } catch (CommonFSUtils.StreamLacksCapabilityException exception) {
      throw new IOException("Can't create writer instance because underlying FileSystem " +
          "doesn't support needed stream capabilities.", exception);
    }
    if (!initialized) {
      LOG.info("storing initial writer instance in case file rolling isn't allowed.");
      noRollsWriter = writer;
    }
    return writer;
  } else {
    LOG.info("WAL rolling disabled, returning the first writer.");
    // Initial assignment happens during the constructor call, so there ought not be
    // a race for first assignment.
    return noRollsWriter;
  }
}

/**
 * public because of FSHLog. Should be package-private
 */
public static Writer createWriter(final Configuration conf, final FileSystem fs, final Path path,
    final boolean overwritable) throws IOException {
  // Configuration already does caching for the Class lookup.
  Class<? extends Writer> logWriterClass = conf.getClass("hbase.regionserver.hlog.writer.impl",
    ProtobufLogWriter.class, Writer.class);
  Writer writer = null;
  try {
    writer = logWriterClass.getDeclaredConstructor().newInstance();
    writer.init(fs, path, conf, overwritable);
    return writer;
  } catch (Exception e) { 
    if (e instanceof CommonFSUtils.StreamLacksCapabilityException) {
      LOG.error("The RegionServer write ahead log provider for FileSystem implementations " +
          "relies on the ability to call " + e.getMessage() + " for proper operation during " +
          "component failures, but the current FileSystem does not support doing so. Please " +
          "check the config value of '" + CommonFSUtils.HBASE_WAL_DIR + "' and ensure " +
          "it points to a FileSystem mount that has suitable capabilities for output streams.");
    } else {
      LOG.debug("Error instantiating log writer.", e);
    }
    if (writer != null) {
      try{
        writer.close();
      } catch(IOException ee){
        LOG.error("cannot close log writer", ee);
      }
    }
    throw new IOException("cannot get log writer", e);
  }
}

@Override
protected String getWriterClassName() {
  return ProtobufLogWriter.class.getSimpleName();
}