com.cloudera.hadoop.hdfs.nfs.nfs4.handlers.RENAMEHandler.java Source code

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Here is the source code for com.cloudera.hadoop.hdfs.nfs.nfs4.handlers.RENAMEHandler.java

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/**
 * Copyright 2011 The Apache Software Foundation
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with this
 * work for additional information regarding copyright ownership. The ASF
 * licenses this file to you 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 at
 *
 * 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 com.cloudera.hadoop.hdfs.nfs.nfs4.handlers;

import static com.cloudera.hadoop.hdfs.nfs.nfs4.Constants.*;

import java.io.IOException;

import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;

import com.cloudera.hadoop.hdfs.nfs.nfs4.ChangeInfo;
import com.cloudera.hadoop.hdfs.nfs.nfs4.NFS4Exception;
import com.cloudera.hadoop.hdfs.nfs.nfs4.NFS4Handler;
import com.cloudera.hadoop.hdfs.nfs.nfs4.Session;
import com.cloudera.hadoop.hdfs.nfs.nfs4.requests.RENAMERequest;
import com.cloudera.hadoop.hdfs.nfs.nfs4.responses.RENAMEResponse;
import org.apache.log4j.Logger;

public class RENAMEHandler extends OperationRequestHandler<RENAMERequest, RENAMEResponse> {

    protected static final Logger LOGGER = Logger.getLogger(RENAMEHandler.class);

    @Override
    protected RENAMEResponse doHandle(NFS4Handler server, Session session, RENAMERequest request)
            throws NFS4Exception, IOException {
        if (session.getCurrentFileHandle() == null || session.getSavedFileHandle() == null) {
            throw new NFS4Exception(NFS4ERR_NOFILEHANDLE);
        }
        if ("".equals(request.getOldName()) || "".equals(request.getNewName())) {
            throw new NFS4Exception(NFS4ERR_INVAL);
        }
        FileSystem fs = session.getFileSystem();
        Path oldParentPath = server.getPath(session.getSavedFileHandle());
        Path oldPath = new Path(oldParentPath, request.getOldName());
        Path newParentPath = server.getPath(session.getCurrentFileHandle());
        Path newPath = new Path(newParentPath, request.getNewName());
        if (!(fs.getFileStatus(oldParentPath).isDir() && fs.getFileStatus(newParentPath).isDir())) {
            throw new NFS4Exception(NFS4ERR_NOTDIR);
        }
        if (!server.fileExists(fs, oldPath)) {
            throw new NFS4Exception(NFS4ERR_NOENT, "Path " + oldPath + " does not exist.");
        }
        if (server.fileExists(fs, newPath)) {
            // TODO according to the RFC we are supposed to check to see if 
            // the entry which exists is compatible (overwrite file and 
            // empty directory if the "old" item is a file or dir respectively.
            throw new NFS4Exception(NFS4ERR_EXIST, "Path " + newPath + " exists.");
        }
        // we won't support renaming files which are open
        // but it happens fairly often that due to tcp/ip
        // the rename request is received before the close.
        // Below we delay the rename if the file is open 
        for (int i = 0; i < 5; i++) {
            if (!server.isFileOpen(oldPath)) {
                break;
            }
            try {
                Thread.sleep(100L);
            } catch (InterruptedException e) {
                throw new IOException("Interrupted while waiting for file to close", e);
            }
        }
        if (server.isFileOpen(oldPath)) {
            throw new NFS4Exception(NFS4ERR_FILE_OPEN);
        }
        LOGGER.info(session.getSessionID() + " Renaming " + oldPath + " to " + newPath);
        long beforeSource = fs.getFileStatus(oldParentPath).getModificationTime();
        long beforeDest = fs.getFileStatus(newParentPath).getModificationTime();
        if (!fs.rename(oldPath, newPath)) {
            throw new NFS4Exception(NFS4ERR_IO);
        }
        long afterSource = fs.getFileStatus(oldParentPath).getModificationTime();
        long afterDest = fs.getFileStatus(newParentPath).getModificationTime();
        RENAMEResponse response = createResponse();
        response.setChangeInfoSource(ChangeInfo.newChangeInfo(true, beforeSource, afterSource));
        response.setChangeInfoDest(ChangeInfo.newChangeInfo(true, beforeDest, afterDest));
        response.setStatus(NFS4_OK);
        return response;
    }

    @Override
    protected RENAMEResponse createResponse() {
        return new RENAMEResponse();
    }
}