Package org.apache.hadoop.hdfs.server.datanode.fsdataset.impl

Class FsDatasetUtil

java.lang.Object

org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsDatasetUtil

@Private
public class FsDatasetUtil
extends java.lang.Object

Utility methods.

Constructor Summary

Constructors

Constructor	Description
FsDatasetUtil()

Method Summary

Modifier and Type	Method	Description
static void	computeChecksum(java.io.File srcMeta, java.io.File dstMeta, java.io.File blockFile, int smallBufferSize, org.apache.hadoop.conf.Configuration conf)	Compute the checksum for a block file that does not already have its checksum computed, and save it to dstMeta file.
static byte[]	createNullChecksumByteArray()
static void	deleteMappedFile(java.lang.String filePath)
static java.io.File	findMetaFile(java.io.File blockFile)	Find the corresponding meta data file from a given block file
static java.io.InputStream	getDirectInputStream(long addr, long length)
static java.io.InputStream	getInputStreamAndSeek(java.io.File file, long offset)
static java.io.FileDescriptor	openAndSeek(java.io.File file, long offset)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FsDatasetUtil

public FsDatasetUtil()

Method Detail

createNullChecksumByteArray

public static byte[] createNullChecksumByteArray()

findMetaFile

public static java.io.File findMetaFile(java.io.File blockFile)
                                 throws java.io.IOException

Find the corresponding meta data file from a given block file

Throws:

java.io.IOException

openAndSeek

public static java.io.FileDescriptor openAndSeek(java.io.File file,
                                                 long offset)
                                          throws java.io.IOException

Throws:

java.io.IOException

getInputStreamAndSeek

public static java.io.InputStream getInputStreamAndSeek(java.io.File file,
                                                        long offset)
                                                 throws java.io.IOException

Throws:

java.io.IOException

getDirectInputStream

public static java.io.InputStream getDirectInputStream(long addr,
                                                       long length)
                                                throws java.io.IOException

Throws:

java.io.IOException

computeChecksum

public static void computeChecksum(java.io.File srcMeta,
                                   java.io.File dstMeta,
                                   java.io.File blockFile,
                                   int smallBufferSize,
                                   org.apache.hadoop.conf.Configuration conf)
                            throws java.io.IOException

Compute the checksum for a block file that does not already have its checksum computed, and save it to dstMeta file.

Throws:

java.io.IOException

deleteMappedFile

public static void deleteMappedFile(java.lang.String filePath)
                             throws java.io.IOException

Throws:

java.io.IOException