AbstractHFileReader.Scanner (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.io.hfile.AbstractHFileReader.Scanner

All Implemented Interfaces:

HFileScanner

Direct Known Subclasses:

HFileReaderV2.AbstractScannerV2

Enclosing class:

AbstractHFileReader
```
protected abstract static class AbstractHFileReader.Scanner
extends Object
implements HFileScanner
```

Field Summary

Fields
Modifier and Type	Field and Description
`protected ByteBuffer`	`blockBuffer`
`protected AtomicInteger`	`blockFetches`
`protected boolean`	`cacheBlocks`
`protected int`	`currKeyLen`
`protected long`	`currMemstoreTS`
`protected int`	`currMemstoreTSLen`
`protected int`	`currValueLen`
`protected boolean`	`isCompaction`
`protected boolean`	`pread`
`protected HFile.Reader`	`reader`

Constructor Summary

Constructors
Constructor and Description
`AbstractHFileReader.Scanner(HFile.Reader reader, boolean cacheBlocks, boolean pread, boolean isCompaction)`

Method Summary

Methods
Modifier and Type	Method and Description
`protected void`	`assertSeeked()`
`void`	`close()` Close the stream socket to handle RS CLOSE_WAIT.
`HFile.Reader`	`getReader()`
`boolean`	`isSeeked()`
`int`	`reseekTo(byte[] key)` Reseek to or just before the passed `key`.
`boolean`	`seekBefore(byte[] key)` Consider the key stream of all the keys in the file, `k[0] ..`
`int`	`seekTo(byte[] key)` SeekTo or just before the passed `key`.
`String`	`toString()`

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

Methods inherited from interface org.apache.hadoop.hbase.io.hfile.HFileScanner
getKey, getKeyString, getKeyValue, getNextIndexedKey, getValue, getValueString, next, reseekTo, reseekTo, seekBefore, seekBefore, seekTo, seekTo, seekTo

- Field Detail
  - blockBuffer
```
protected ByteBuffer blockBuffer
```
  - cacheBlocks
```
protected boolean cacheBlocks
```
  - pread
```
protected final boolean pread
```
  - isCompaction
```
protected final boolean isCompaction
```
  - currKeyLen
```
protected int currKeyLen
```
  - currValueLen
```
protected int currValueLen
```
  - currMemstoreTSLen
```
protected int currMemstoreTSLen
```
  - currMemstoreTS
```
protected long currMemstoreTS
```
  - blockFetches
```
protected AtomicInteger blockFetches
```
  - reader
```
protected final HFile.Reader reader
```
- Constructor Detail
  - AbstractHFileReader.Scanner
```
public AbstractHFileReader.Scanner(HFile.Reader reader,
                           boolean cacheBlocks,
                           boolean pread,
                           boolean isCompaction)
```
- Method Detail
  - isSeeked
```
public boolean isSeeked()
```
    Specified by:
    
    isSeeked in interface HFileScanner
    
    Returns:
    True is scanner has had one of the seek calls invoked; i.e. HFileScanner.seekBefore(byte[]) or HFileScanner.seekTo() or HFileScanner.seekTo(byte[]). Otherwise returns false.
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - assertSeeked
```
protected void assertSeeked()
```
  - seekTo
```
public int seekTo(byte[] key)
           throws IOException
```
    Description copied from interface: HFileScanner
    
    SeekTo or just before the passed key. Examine the return code to figure whether we found the key or not. Consider the key stream of all the keys in the file, k[0] .. k[n], where there are n keys in the file.
    
    Specified by:
    
    seekTo in interface HFileScanner
    
    Parameters:
    key - Key to find.
    
    Returns:
    -1, if key < k[0], no position; 0, such that k[i] = key and scanner is left in position i; and 1, such that k[i] < key, and scanner is left in position i. The scanner will position itself between k[i] and k[i+1] where k[i] < key <= k[i+1]. If there is no key k[i+1] greater than or equal to the input key, then the scanner will position itself at the end of the file and next() will return false when it is called.
    
    Throws:
    
    IOException
  - seekBefore
```
public boolean seekBefore(byte[] key)
                   throws IOException
```
    Description copied from interface: HFileScanner
    
    Consider the key stream of all the keys in the file, k[0] .. k[n], where there are n keys in the file.
    
    Specified by:
    
    seekBefore in interface HFileScanner
    
    Parameters:
    key - Key to find
    
    Returns:
    false if key <= k[0] or true with scanner in position 'i' such that: k[i] < key. Furthermore: there may be a k[i+1], such that k[i] < key <= k[i+1] but there may also NOT be a k[i+1], and next() will return false (EOF).
    
    Throws:
    
    IOException
  - reseekTo
```
public int reseekTo(byte[] key)
             throws IOException
```
    Description copied from interface: HFileScanner
    
    Reseek to or just before the passed key. Similar to seekTo except that this can be called even if the scanner is not at the beginning of a file. This can be used to seek only to keys which come after the current position of the scanner. Consider the key stream of all the keys in the file, k[0] .. k[n], where there are n keys in the file after current position of HFileScanner. The scanner will position itself between k[i] and k[i+1] where k[i] < key <= k[i+1]. If there is no key k[i+1] greater than or equal to the input key, then the scanner will position itself at the end of the file and next() will return false when it is called.
    
    Specified by:
    
    reseekTo in interface HFileScanner
    
    Parameters:
    key - Key to find (should be non-null)
    
    Returns:
    -1, if key < k[0], no position; 0, such that k[i] = key and scanner is left in position i; and 1, such that k[i] < key, and scanner is left in position i.
    
    Throws:
    
    IOException
  - getReader
```
public HFile.Reader getReader()
```
    Specified by:
    
    getReader in interface HFileScanner
    
    Returns:
    Reader that underlies this Scanner instance.
  - close
```
public void close()
```
    Description copied from interface: HFileScanner
    
    Close the stream socket to handle RS CLOSE_WAIT. HBASE-9393
    
    Specified by:
    
    close in interface HFileScanner

Class AbstractHFileReader.Scanner

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.apache.hadoop.hbase.io.hfile.HFileScanner

Field Detail

blockBuffer

cacheBlocks

pread

isCompaction

currKeyLen

currValueLen

currMemstoreTSLen

currMemstoreTS

blockFetches

reader

Constructor Detail

AbstractHFileReader.Scanner

Method Detail

isSeeked

toString

assertSeeked

seekTo

seekBefore

reseekTo

getReader

close