org.apache.hadoop.hive.metastore

Class FileMetadataHandler

java.lang.Object

org.apache.hadoop.hive.metastore.FileMetadataHandler

Direct Known Subclasses:

OrcFileMetadataHandler

public abstract class FileMetadataHandler
extends Object

The base implementation of a file metadata handler for a specific file type. There are currently two classes for each file type (of 1), this one, which is very simple due to the fact that it just calls the proxy class for most calls; and the proxy class, that contains the actual implementation that depends on some stuff in QL (for ORC).

Field Summary

Fields

Modifier and Type	Field and Description
protected static org.apache.commons.logging.Log	LOG

Constructor Summary

Constructors

Constructor and Description
FileMetadataHandler()

Method Summary

Modifier and Type	Method and Description
void	cacheFileMetadata(long fileId, org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.fs.Path path) Caches the file metadata for a particular file.
void	configure(org.apache.hadoop.conf.Configuration conf, PartitionExpressionProxy expressionProxy, MetadataStore store) Configures the handler.
ByteBuffer[]	createAddedCols()
ByteBuffer[][]	createAddedColVals(List<ByteBuffer> metadata)
protected PartitionExpressionProxy	getExpressionProxy()
protected FileFormatProxy	getFileFormatProxy()
abstract void	getFileMetadataByExpr(List<Long> fileIds, byte[] expr, ByteBuffer[] metadatas, ByteBuffer[] results, boolean[] eliminated) Same as RawStore.getFileMetadataByExpr.
protected MetadataStore	getStore()
protected abstract org.apache.hadoop.hive.metastore.api.FileMetadataExprType	getType()

Methods inherited from class java.lang.Object

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

Field Detail

LOG

protected static final org.apache.commons.logging.Log LOG

Constructor Detail

FileMetadataHandler

public FileMetadataHandler()

Method Detail

getFileMetadataByExpr

public abstract void getFileMetadataByExpr(List<Long> fileIds,
                                           byte[] expr,
                                           ByteBuffer[] metadatas,
                                           ByteBuffer[] results,
                                           boolean[] eliminated)
                                    throws IOException

Same as RawStore.getFileMetadataByExpr.

Throws:

IOException

getType

protected abstract org.apache.hadoop.hive.metastore.api.FileMetadataExprType getType()

getExpressionProxy

protected PartitionExpressionProxy getExpressionProxy()

getFileFormatProxy

protected FileFormatProxy getFileFormatProxy()

getStore

protected MetadataStore getStore()

configure

public void configure(org.apache.hadoop.conf.Configuration conf,
                      PartitionExpressionProxy expressionProxy,
                      MetadataStore store)

Configures the handler. Called once before use.

Parameters:

conf - Config.

expressionProxy - Expression proxy to access ql stuff.

store - Storage interface to manipulate the metadata.

cacheFileMetadata

public void cacheFileMetadata(long fileId,
                              org.apache.hadoop.fs.FileSystem fs,
                              org.apache.hadoop.fs.Path path)
                       throws IOException,
                              InterruptedException

Caches the file metadata for a particular file.

Parameters:

fileId - File id.

fs - The filesystem of the file.

path - Path to the file.

Throws:

IOException

InterruptedException

createAddedCols

public ByteBuffer[] createAddedCols()

Returns:

the added column names to be cached in metastore with the metadata for this type.

createAddedColVals

public ByteBuffer[][] createAddedColVals(List<ByteBuffer> metadata)

Returns:

the values for the added columns returned by createAddedCols for respective metadatas.