public class ArrowFileReader extends ArrowReader
ArrowReader
that reads the standard arrow binary
file format.DictionaryProvider.MapDictionaryProvider
allocator, dictionaries
Constructor and Description |
---|
ArrowFileReader(SeekableByteChannel in,
BufferAllocator allocator) |
ArrowFileReader(SeekableByteChannel in,
BufferAllocator allocator,
CompressionCodec.Factory compressionFactory) |
ArrowFileReader(SeekableReadChannel in,
BufferAllocator allocator) |
ArrowFileReader(SeekableReadChannel in,
BufferAllocator allocator,
CompressionCodec.Factory compressionFactory) |
Modifier and Type | Method and Description |
---|---|
long |
bytesRead()
Return the number of bytes read from the ReadChannel.
|
protected void |
closeReadSource()
Close the underlying read source.
|
List<ArrowBlock> |
getDictionaryBlocks() |
Map<String,String> |
getMetaData()
Get custom metadata.
|
List<ArrowBlock> |
getRecordBlocks()
Returns the
ArrowBlock metadata from the file. |
void |
initialize()
Reads the schema and initializes the vectors.
|
boolean |
loadNextBatch()
Returns true if a batch was read, false if no more batches.
|
boolean |
loadRecordBatch(ArrowBlock block)
Loads record batch for the given block.
|
ArrowDictionaryBatch |
readDictionary()
Read a dictionary batch from the source, will be invoked after the schema has been read and
called N times, where N is the number of dictionaries indicated by the schema Fields.
|
protected Schema |
readSchema()
Read the Schema from the source, will be invoked at the beginning the initialization.
|
close, close, ensureInitialized, getDictionaryIds, getDictionaryVectors, getVectorSchemaRoot, loadDictionary, loadRecordBatch, lookup, prepareLoadNextBatch
public ArrowFileReader(SeekableReadChannel in, BufferAllocator allocator, CompressionCodec.Factory compressionFactory)
public ArrowFileReader(SeekableByteChannel in, BufferAllocator allocator, CompressionCodec.Factory compressionFactory)
public ArrowFileReader(SeekableReadChannel in, BufferAllocator allocator)
public ArrowFileReader(SeekableByteChannel in, BufferAllocator allocator)
public long bytesRead()
ArrowReader
bytesRead
in class ArrowReader
protected void closeReadSource() throws IOException
ArrowReader
closeReadSource
in class ArrowReader
IOException
- on errorprotected Schema readSchema() throws IOException
ArrowReader
readSchema
in class ArrowReader
IOException
- on errorpublic void initialize() throws IOException
ArrowReader
initialize
in class ArrowReader
IOException
public ArrowDictionaryBatch readDictionary() throws IOException
IOException
- on errorpublic boolean loadNextBatch() throws IOException
loadNextBatch
in class ArrowReader
IOException
- on errorpublic List<ArrowBlock> getDictionaryBlocks() throws IOException
IOException
public List<ArrowBlock> getRecordBlocks() throws IOException
ArrowBlock
metadata from the file.IOException
public boolean loadRecordBatch(ArrowBlock block) throws IOException
IOException
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