Java JspHelper.bestNode方法代码示例

import org.apache.hadoop.hdfs.server.common.JspHelper; //导入方法依赖的package包/类
/** Select a datanode to service this request.
 * Currently, this looks at no more than the first five blocks of a file,
 * selecting a datanode randomly from the most represented.
 * @param conf 
 */
private DatanodeID pickSrcDatanode(LocatedBlocks blks, HdfsFileStatus i,
    Configuration conf) throws IOException {
  if (i.getLen() == 0 || blks.getLocatedBlocks().size() <= 0) {
    // pick a random datanode
    NameNode nn = NameNodeHttpServer.getNameNodeFromContext(
        getServletContext());
    return NamenodeJspHelper.getRandomDatanode(nn);
  }
  return JspHelper.bestNode(blks, conf);
}
 

import org.apache.hadoop.hdfs.server.common.JspHelper; //导入方法依赖的package包/类
/**
 * Select a datanode to service this request.
 * Currently, this looks at no more than the first five blocks of a file,
 * selecting a datanode randomly from the most represented.
 *
 * @param conf
 */
private DatanodeID pickSrcDatanode(LocatedBlocks blks, HdfsFileStatus i,
    Configuration conf) throws IOException {
  if (i.getLen() == 0 || blks.getLocatedBlocks().size() <= 0) {
    // pick a random datanode
    NameNode nn =
        NameNodeHttpServer.getNameNodeFromContext(getServletContext());
    return NamenodeJspHelper.getRandomDatanode(nn);
  }
  return JspHelper.bestNode(blks, conf);
}
 

import org.apache.hadoop.hdfs.server.common.JspHelper; //导入方法依赖的package包/类
/** Select a datanode to service this request.
 * Currently, this looks at no more than the first five blocks of a file,
 * selecting a datanode randomly from the most represented.
 */
private DatanodeID pickSrcDatanode(String parent, HdfsFileStatus i,
    ClientProtocol nnproxy) throws IOException {
  final LocatedBlocks blks = nnproxy.getBlockLocations(
      i.getFullPath(new Path(parent)).toUri().getPath(), 0, 1);
  if (i.getLen() == 0 || blks.getLocatedBlocks().size() <= 0) {
    // pick a random datanode
    NameNode nn = (NameNode)getServletContext().getAttribute("name.node");
    return nn.getNamesystem().getRandomDatanode();
  }
  return JspHelper.bestNode(blks);
}
 

import org.apache.hadoop.hdfs.server.common.JspHelper; //导入方法依赖的package包/类
private static String generateLinksForAdjacentBlock(final int direction,
    String authority, int datanodePort, long startOffset,
    int chunkSizeToView, long blockSize, long blockId, Long genStamp,
    final DFSClient dfs, final String filename, final Configuration conf,
    final String scheme, final String tokenString,
    final int namenodeInfoPort, final String nnAddr)
    throws AccessControlException, FileNotFoundException,
    UnresolvedLinkException, IOException {

  boolean found = false;
  if ((direction == NEXT_BLOCK && startOffset + chunkSizeToView < blockSize)
      || (direction == PREV_BLOCK && startOffset != 0)) {
    // we are in the same block
    found = true;

    if (direction == NEXT_BLOCK) {
      startOffset = startOffset + chunkSizeToView;
    } else {
      startOffset = Math.max(0, startOffset - chunkSizeToView);
    }
  } else {
    List<LocatedBlock> blocks = dfs.getNamenode().getBlockLocations(filename, 0,
        Long.MAX_VALUE).getLocatedBlocks();

    final long curBlockId = blockId;
    int curBlockIdx = Iterables.indexOf(blocks, new Predicate<LocatedBlock>() {
      @Override
      public boolean apply(LocatedBlock b) {
        return b.getBlock().getBlockId() == curBlockId;
      }
    });
    found = curBlockIdx != -1 &&
        ((direction == NEXT_BLOCK && curBlockIdx < blocks.size() - 1)
            || (direction == PREV_BLOCK && curBlockIdx > 0));

    if (found) {
      LocatedBlock nextBlock = blocks.get(curBlockIdx + direction);

      blockId = nextBlock.getBlock().getBlockId();
      genStamp = nextBlock.getBlock().getGenerationStamp();
      startOffset = 0;
      blockSize = nextBlock.getBlock().getNumBytes();
      DatanodeInfo d = JspHelper.bestNode(nextBlock, conf);
      datanodePort = d.getXferPort();
      authority = JspHelper.Url.authority(scheme, d);
    }
  }

  if (found) {
    return "///" + authority
        + "/browseBlock.jsp?blockId=" + blockId
        + "&blockSize=" + blockSize
        + "&startOffset=" + startOffset
        + "&genstamp=" + genStamp
        + "&filename=" + URLEncoder.encode(filename, "UTF-8")
        + "&chunkSizeToView=" + chunkSizeToView
        + "&datanodePort=" + datanodePort
        + "&namenodeInfoPort=" + namenodeInfoPort
        + JspHelper.getDelegationTokenUrlParam(tokenString)
        + JspHelper.getUrlParam(JspHelper.NAMENODE_ADDRESS, nnAddr);
  } else {
    return null;
  }
}
 

import org.apache.hadoop.hdfs.server.common.JspHelper; //导入方法依赖的package包/类
static DatanodeInfo chooseDatanode(final NameNode namenode,
    final String path, final HttpOpParam.Op op, final long openOffset,
    final long blocksize, Configuration conf) throws IOException {
  final BlockManager bm = namenode.getNamesystem().getBlockManager();

  if (op == PutOpParam.Op.CREATE) {
    //choose a datanode near to client 
    final DatanodeDescriptor clientNode = bm.getDatanodeManager(
        ).getDatanodeByHost(getRemoteAddress());
    if (clientNode != null) {
      final DatanodeDescriptor[] datanodes = bm.getBlockPlacementPolicy()
          .chooseTarget(path, 1, clientNode,
              new ArrayList<DatanodeDescriptor>(), false, null, blocksize);
      if (datanodes.length > 0) {
        return datanodes[0];
      }
    }
  } else if (op == GetOpParam.Op.OPEN
      || op == GetOpParam.Op.GETFILECHECKSUM
      || op == PostOpParam.Op.APPEND) {
    //choose a datanode containing a replica 
    final NamenodeProtocols np = namenode.getRpcServer();
    final HdfsFileStatus status = np.getFileInfo(path);
    if (status == null) {
      throw new FileNotFoundException("File " + path + " not found.");
    }
    final long len = status.getLen();
    if (op == GetOpParam.Op.OPEN) {
      if (openOffset < 0L || (openOffset >= len && len > 0)) {
        throw new IOException("Offset=" + openOffset
            + " out of the range [0, " + len + "); " + op + ", path=" + path);
      }
    }

    if (len > 0) {
      final long offset = op == GetOpParam.Op.OPEN? openOffset: len - 1;
      final LocatedBlocks locations = np.getBlockLocations(path, offset, 1);
      final int count = locations.locatedBlockCount();
      if (count > 0) {
        return JspHelper.bestNode(locations.get(0).getLocations(), false, conf);
      }
    }
  } 

  return (DatanodeDescriptor)bm.getDatanodeManager().getNetworkTopology(
      ).chooseRandom(NodeBase.ROOT);
}
 

import org.apache.hadoop.hdfs.server.common.JspHelper; //导入方法依赖的package包/类
static DatanodeInfo chooseDatanode(final NameNode namenode, final String path,
    final HttpOpParam.Op op, final long openOffset, final long blocksize,
    Configuration conf) throws IOException {
  final BlockManager bm = namenode.getNamesystem().getBlockManager();

  if (op == PutOpParam.Op.CREATE) {
    //choose a datanode near to client 
    final DatanodeDescriptor clientNode =
        bm.getDatanodeManager().getDatanodeByHost(getRemoteAddress());
    if (clientNode != null) {
      final DatanodeDescriptor[] datanodes = bm.getBlockPlacementPolicy()
          .chooseTarget(path, 1, clientNode,
              new ArrayList<DatanodeDescriptor>(), false, null, blocksize);
      if (datanodes.length > 0) {
        return datanodes[0];
      }
    }
  } else if (op == GetOpParam.Op.OPEN ||
      op == GetOpParam.Op.GETFILECHECKSUM || op == PostOpParam.Op.APPEND) {
    //choose a datanode containing a replica 
    final NamenodeProtocols np = namenode.getRpcServer();
    final HdfsFileStatus status = np.getFileInfo(path);
    if (status == null) {
      throw new FileNotFoundException("File " + path + " not found.");
    }
    final long len = status.getLen();
    if (op == GetOpParam.Op.OPEN) {
      if (openOffset < 0L || (openOffset >= len && len > 0)) {
        throw new IOException(
            "Offset=" + openOffset + " out of the range [0, " + len + "); " +
                op + ", path=" + path);
      }
    }

    if (len > 0) {
      final long offset = op == GetOpParam.Op.OPEN ? openOffset : len - 1;
      final LocatedBlocks locations = np.getBlockLocations(path, offset, 1);
      final int count = locations.locatedBlockCount();
      if (count > 0) {
        return JspHelper
            .bestNode(locations.get(0).getLocations(), false, conf);
      }
    }
  }

  return (DatanodeDescriptor) bm.getDatanodeManager().getNetworkTopology()
      .chooseRandom(NodeBase.ROOT);
}
 

import org.apache.hadoop.hdfs.server.common.JspHelper; //导入方法依赖的package包/类
static void generateFileChunksForTail(JspWriter out, HttpServletRequest req,
                                      Configuration conf
                                      ) throws IOException,
                                               InterruptedException {
  final String referrer = JspHelper.validateURL(req.getParameter("referrer"));
  boolean noLink = false;
  if (referrer == null) {
    noLink = true;
  }

  final String filename = JspHelper
      .validatePath(StringEscapeUtils.unescapeHtml(req.getParameter("filename")));
  if (filename == null) {
    out.print("Invalid input (file name absent)");
    return;
  }
  String tokenString = req.getParameter(JspHelper.DELEGATION_PARAMETER_NAME);
  UserGroupInformation ugi = JspHelper.getUGI(req, conf);

  String namenodeInfoPortStr = req.getParameter("namenodeInfoPort");
  int namenodeInfoPort = -1;
  if (namenodeInfoPortStr != null)
    namenodeInfoPort = Integer.parseInt(namenodeInfoPortStr);

  final int chunkSizeToView = JspHelper.string2ChunkSizeToView(req
      .getParameter("chunkSizeToView"), getDefaultChunkSize(conf));

  if (!noLink) {
    out.print("<h3>Tail of File: ");
    JspHelper.printPathWithLinks(filename, out, namenodeInfoPort, 
                                 tokenString);
    out.print("</h3><hr>");
    out.print("<a href=\"" + referrer + "\">Go Back to File View</a><hr>");
  } else {
    out.print("<h3>" + filename + "</h3>");
  }
  out.print("<b>Chunk size to view (in bytes, up to file's DFS block size): </b>");
  out.print("<input type=\"text\" name=\"chunkSizeToView\" value="
      + chunkSizeToView + " size=10 maxlength=10>");
  out.print("&nbsp;&nbsp;<input type=\"submit\" name=\"submit\" value=\"Refresh\"><hr>");
  out.print("<input type=\"hidden\" name=\"filename\" value=\"" + filename
      + "\">");
  out.print("<input type=\"hidden\" name=\"namenodeInfoPort\" value=\""
      + namenodeInfoPort + "\">");
  if (!noLink)
    out.print("<input type=\"hidden\" name=\"referrer\" value=\"" + referrer
        + "\">");

  // fetch the block from the datanode that has the last block for this file
  final DFSClient dfs = getDFSClient(ugi, datanode.getNameNodeAddrForClient(), conf);
  List<LocatedBlock> blocks = dfs.getNamenode().getBlockLocations(filename, 0,
      Long.MAX_VALUE).getLocatedBlocks();
  if (blocks == null || blocks.size() == 0) {
    out.print("No datanodes contain blocks of file " + filename);
    dfs.close();
    return;
  }
  LocatedBlock lastBlk = blocks.get(blocks.size() - 1);
  long blockSize = lastBlk.getBlock().getNumBytes();
  long blockId = lastBlk.getBlock().getBlockId();
  Token<BlockTokenIdentifier> accessToken = lastBlk.getBlockToken();
  long genStamp = lastBlk.getBlock().getGenerationStamp();
  DatanodeInfo chosenNode;
  try {
    chosenNode = JspHelper.bestNode(lastBlk);
  } catch (IOException e) {
    out.print(e.toString());
    dfs.close();
    return;
  }
  InetSocketAddress addr = NetUtils.createSocketAddr(chosenNode.getName());
  // view the last chunkSizeToView bytes while Tailing
  final long startOffset = blockSize >= chunkSizeToView ? blockSize
      - chunkSizeToView : 0;

  out.print("<textarea cols=\"100\" rows=\"25\" wrap=\"virtual\" style=\"width:100%\" READONLY>");
  JspHelper.streamBlockInAscii(addr, blockId, accessToken, genStamp,
      blockSize, startOffset, chunkSizeToView, out, conf);
  out.print("</textarea>");
  dfs.close();
}