WALEntryStream (Apache HBase 1.4.11 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(PriorityBlockingQueue<org.apache.hadoop.fs.Path> logQueue, org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.conf.Configuration conf, long startPosition, MetricsSource metrics)` Create an entry stream over the given queue at the given start position
`WALEntryStream(PriorityBlockingQueue<org.apache.hadoop.fs.Path> logQueue, org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.conf.Configuration conf, MetricsSource metrics)` 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(PriorityBlockingQueue<org.apache.hadoop.fs.Path> logQueue,
              org.apache.hadoop.fs.FileSystem fs,
              org.apache.hadoop.conf.Configuration conf,
              MetricsSource metrics)
               throws IOException
```
    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
    
    Throws:
    
    IOException
  - WALEntryStream
```
public WALEntryStream(PriorityBlockingQueue<org.apache.hadoop.fs.Path> logQueue,
              org.apache.hadoop.fs.FileSystem fs,
              org.apache.hadoop.conf.Configuration conf,
              long startPosition,
              MetricsSource metrics)
               throws IOException
```
    Create an entry stream over the given queue at the given start position
    
    Parameters:
    logQueue - the queue of WAL paths
    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
    
    Throws:
    
    IOException
- 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

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