WALEntryStream (Apache HBase 1.7.1 API)

java.lang.Object
- org.apache.hadoop.hbase.replication.regionserver.WALEntryStream

All Implemented Interfaces:

Closeable, AutoCloseable, Iterable<WAL.Entry>, Iterator<WAL.Entry>
```
@InterfaceAudience.Private
@InterfaceStability.Evolving
public class WALEntryStream
extends Object
implements Iterator<WAL.Entry>, Closeable, Iterable<WAL.Entry>
```
Streaming access to WAL entries. This class is given a queue of WAL Path, and continually iterates through all the WAL WAL.Entry in the queue. When it's done reading from a Path, it dequeues it and starts reading from the next.

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class WALEntryStream.WALEntryStreamRuntimeException

Nested Classes
Modifier and Type	Class and Description
`static class`	`WALEntryStream.WALEntryStreamRuntimeException`

Constructor Summary

Constructors
Constructor and Description
`WALEntryStream(ReplicationSourceLogQueue logQueue, org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.conf.Configuration conf, long startPosition, MetricsSource metrics, String walGroupId)` Create an entry stream over the given queue at the given start position
`WALEntryStream(ReplicationSourceLogQueue logQueue, org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.conf.Configuration conf, MetricsSource metrics, String walGroupId)` Create an entry stream over the given queue

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`close()`
`org.apache.hadoop.fs.Path`	`getCurrentPath()`
`long`	`getPosition()`
`boolean`	`hasNext()`
`Iterator<WAL.Entry>`	`iterator()`
`WAL.Entry`	`next()`
`void`	`remove()` Not supported.
`void`	`reset()` Should be called if the stream is to be reused (i.e.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - WALEntryStream
```
public WALEntryStream(ReplicationSourceLogQueue logQueue,
              org.apache.hadoop.fs.FileSystem fs,
              org.apache.hadoop.conf.Configuration conf,
              MetricsSource metrics,
              String walGroupId)
```
    Create an entry stream over the given queue
    
    Parameters:
    logQueue - the queue of WAL paths
    fs - FileSystem to use to create WAL.Reader for this stream
    conf - Configuration to use to create WAL.Reader for this stream
    metrics - replication metrics
    walGroupId - wal prefix
  - WALEntryStream
```
public WALEntryStream(ReplicationSourceLogQueue logQueue,
              org.apache.hadoop.fs.FileSystem fs,
              org.apache.hadoop.conf.Configuration conf,
              long startPosition,
              MetricsSource metrics,
              String walGroupId)
```
    Create an entry stream over the given queue at the given start position
    
    Parameters:
    logQueue - the queue of WAL paths
    fs - FileSystem to use to create WAL.Reader for this stream
    conf - the Configuration to use to create WAL.Reader for this stream
    startPosition - the position in the first WAL to start reading at
    metrics - the replication metrics
    walGroupId - wal prefix
- Method Detail
  - hasNext
```
public boolean hasNext()
```
    Specified by:
    
    hasNext in interface Iterator<WAL.Entry>
    
    Returns:
    true if there is another WAL WAL.Entry
    
    Throws:
    
    WALEntryStream.WALEntryStreamRuntimeException - if there was an Exception while reading
  - next
```
public WAL.Entry next()
```
    Specified by:
    
    next in interface Iterator<WAL.Entry>
    
    Returns:
    the next WAL entry in this stream
    
    Throws:
    
    WALEntryStream.WALEntryStreamRuntimeException - if there was an IOException
    
    NoSuchElementException - if no more entries in the stream.
  - remove
```
public void remove()
```
    Not supported.
    
    Specified by:
    
    remove in interface Iterator<WAL.Entry>
  - close
```
public void close()
           throws IOException
```
    Specified by:
    
    close in interface Closeable
    
    Specified by:
    
    close in interface AutoCloseable
    
    Throws:
    
    IOException
  - iterator
```
public Iterator<WAL.Entry> iterator()
```
    Specified by:
    
    iterator in interface Iterable<WAL.Entry>
    
    Returns:
    the iterator over WAL entries in the queue.
  - getPosition
```
public long getPosition()
```
    Returns:
    the position of the last Entry returned by next()
  - getCurrentPath
```
public org.apache.hadoop.fs.Path getCurrentPath()
```
    Returns:
    the Path of the current WAL
  - reset
```
public void reset()
           throws IOException
```
    Should be called if the stream is to be reused (i.e. used again after hasNext() has returned false)
    
    Throws:
    
    IOException - io exception while resetting the reader

Class WALEntryStream

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

WALEntryStream

WALEntryStream

Method Detail

hasNext

next

remove

close

iterator

getPosition

getCurrentPath

reset