Package org.apache.beam.sdk.io

Class BlockBasedSource.Block<T>

java.lang.Object

org.apache.beam.sdk.io.BlockBasedSource.Block<T>

Enclosing class:

BlockBasedSource<T>

protected abstract static class BlockBasedSource.Block<T>
extends Object

A Block represents a block of records that can be read.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	Block()

Method Summary

Modifier and Type	Method	Description
abstract T	getCurrentRecord()	Returns the current record.
abstract double	getFractionOfBlockConsumed()	Returns the fraction of the block already consumed, if possible, as a value in [0, 1].
abstract boolean	readNextRecord()	Reads the next record from the block and returns true iff one exists.

Methods inherited from class java.lang.Object

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

Constructor Details

Block

protected Block()

Method Details

getCurrentRecord

public abstract T getCurrentRecord()

Returns the current record.

readNextRecord

public abstract boolean readNextRecord()
                                throws IOException

Reads the next record from the block and returns true iff one exists.

Throws:

IOException

getFractionOfBlockConsumed

public abstract double getFractionOfBlockConsumed()

Returns the fraction of the block already consumed, if possible, as a value in [0, 1]. It should not include the current record. Successive results from this method must be monotonically increasing.

If it is not possible to compute the fraction of the block consumed this method may return zero. For example, when the total number of records in the block is unknown.